| 0/0 |
2026/07/31 00:45 |
flow |
assessment-security |
32m
Results: map[DenialOfService:false Explanation:**Analysis of the Bug Report**
The bug report indicates a lockdep warning: `WARNING: syz.3.395/6091 still has
locks held!`.
The stack trace shows that the warning is triggered during a firmware update
operation via `devlink_compat_flash_update()`, which is called from the
`dev_ethtool()` ioctl handler.
Here is the sequence of events leading to the warning:
1. `devlink_compat_flash_update()` acquires the devlink instance lock
(`devl_lock(devlink)`).
2. It then calls `request_firmware()` to load the requested firmware file.
3. If the firmware is not found directly on the filesystem and the kernel is
configured with `CONFIG_FW_LOADER_USER_HELPER_FALLBACK` (common in
syzkaller/fuzzing kernels but typically disabled in production), the kernel
falls back to triggering a user mode helper to load the firmware.
4. The user mode helper fallback mechanism calls
`usermodehelper_read_trylock()`, which in turn calls `try_to_freeze()`.
5. `try_to_freeze()` checks if the current thread is holding any locks by
calling `debug_check_no_locks_held()`. Since the devlink lock is held, lockdep
emits a warning.
**Security Impact Assessment**
* **Exploitable:** No. This is purely a lockdep warning indicating a potential
deadlock scenario if the system were to freeze (suspend/hibernate) while the
lock is held. It does not cause memory corruption, out-of-bounds accesses, or
information leaks.
* **Denial of Service:** No. In production kernels, `CONFIG_DEBUG_LOCK_ALLOC`
(lockdep) is disabled, meaning `debug_check_no_locks_held()` is a no-op and the
warning will not even be printed. Furthermore, even if the user mode helper
fallback blocks the thread for the default 60-second timeout, the only lock held
is the specific `devlink->lock_key`. This lock only serializes operations on
that specific devlink device instance (e.g., a virtual `netdevsim` device
created by the user) and does not block system-wide operations or other devices.
* **Accessible From Unprivileged Processes:** No. The `ETHTOOL_FLASHDEV` command
is restricted and requires the caller to have the `CAP_NET_ADMIN` capability in
the network namespace (enforced in `dev_ethtool_locked()`).
* **Accessible From User Namespaces:** Yes. An unprivileged user can create a
new user namespace and a new network namespace, thereby gaining `CAP_NET_ADMIN`
within that namespace. They can then instantiate a virtual device that supports
devlink (like `netdevsim`) and trigger the firmware update path. However, as
established, doing so only affects their own virtual device and has no security
impact on the host system.
**Conclusion**
This is a known lockdep warning related to calling `request_firmware()` while
holding a mutex. It is not a security vulnerability, cannot be exploited for
privilege escalation or memory corruption, and does not cause a system-wide
denial of service. Exploitable:false FilesystemTrigger:false NetworkTrigger:false PeripheralTrigger:false RemoteTrigger:false Unprivileged:false UserNamespace:true VMGuestTrigger:false VMHostTrigger:false]
|
| 1/1 |
2026/07/31 00:45 |
action |
syz-repro-to-c-repro |
0m
Results:
|
| 2/1 |
2026/07/31 00:45 |
action |
kernel-checkouter |
1m
Results: map[KernelSrc:/app/workdir/cache/src/bc72b0baf0345f0b613f258c98b80ee7d9215ac1]
|
| 3/1 |
2026/07/31 00:46 |
action |
kernel-builder |
11m
Results: map[KernelObj:/app/workdir/cache/build/8dbafce49c4e73348834a7f02ab3e9aa0ec73fc5]
|
| 4/1 |
2026/07/31 00:58 |
action |
codesearch-prepare |
16m
Results: map[Index:codesearch-index]
|
| 5/1 |
2026/07/31 01:15 |
agent |
expert |
2m
Model:
Results: map[DenialOfService:false Exploitable:false FilesystemTrigger:false NetworkTrigger:false PeripheralTrigger:false RemoteTrigger:false Unprivileged:false UserNamespace:true VMGuestTrigger:false VMHostTrigger:false]
Instruction: You are an experienced Linux kernel security engineer. Your task is to analyze given kernel bug report
and determine its security impact based on the following dimensions.
Use the provided tools to examine the source code, check for capability checks (e.g., capable(), ns_capable()),
and understand the nature of the bug. Analyze the given kernel build and configuration.
You can check the kernel config by grepping ".config" file; you can check kernel cmdline by grepping
".config" file for "CONFIG_CMDLINE=". Assume sysctl parameters have default values.
But analyze for the corresponding production build w/o debugging tools enabled (like KASAN, KMSAN, UBSAN).
Try different strategies when analyzing the bug:
- think of ways in which the vulnerable code is unreachable
- or the other way around: try to come up with different ideas of how an unprivileged user can reach the bug
If still unsure err on the side of the bug being non-exploitable/not-accessible.
In the final reply, provide a reasoning for your assessment.
Analysis dimensions:
* Exploitable:
Determine if the bug can result in memory corruption, elevated privileges, or an information leak.
Memory safety issues are almost always exploitable (KASAN or UBSAN reports for use-after-free, out-of-bounds;
refcounting issues, corrupted lists, etc). When kernel is crashing on a completely wild pointer access
(e.g. user-space address, or non-canonical address, but not on NULL or address corresponding to KASAN shadow
for NULL address), including both data accesses and control transfers, that also usually implies possibility
of exploitation. Such reports usually say "unable to handle kernel paging request".
Uses of uninitialized values detected by KMSAN may be exploitable b/c attacker frequently can affect uninit
values with spraying techniques. However, for these exploitability depends on how exactly the uninit value
is used in the code, and what it affects.
Information leaks are exploitable on their own and should be classified as such. A bug that copies kernel
memory contents to userspace (e.g. an out-of-bounds read whose result is returned to the caller, or
uninitialized stack/heap bytes written to a user buffer) is exploitable: it can reveal kernel pointer
values and defeat KASLR, expose sensitive data such as cryptographic keys or other processes' memory, and
serves as a necessary building block in most modern kernel privilege-escalation exploit chains. Do not classify
an information leak as non-exploitable solely because it does not directly cause a memory write or control-flow
hijack; the leak itself is the exploit primitive.
Think of what happens after the bug is triggered. Some bugs cause kernel panic and halt execution,
they are harder to exploit. For example, BUG reports halts the kernel. However, WARNING reports don't halt
execution in production builds. Debug bug detection tools (like KASAN, KMSAN, KCSAN, UBSAN) are also not enabled
in production builds, so attacker can freely exploit these bugs w/o being detected by these tools.
If you see an integer overflow, think how the overflowed value used later (if it's used as allocation size,
or an array index). If you see an out-of-bounds read, think if it's followed by an out-of-bounds write as well.
Some KCSAN data-races may be exploitable by skilled attackers as well. Think what data structures got corrupted
as the result of data races and how. However, note that kernel has lots of "benign" data races that don't lead
to any runtime misbehavior at all.
* Denial Of Service:
Determine if the bug can result in denial-of-service. Most bugs can, since they cause system crash,
hangs, deadlocks, or resource leaks. This is mostly applicable to WARNING bugs that won't cause system crash
in production. For these think what will be consequences of the violation of the kernel assumptions flagged
by the WARNING. In some cases the unexpected condition is also properly handled by the normal control flow
(e.g. with "if (WARN_ON(...))"), these won't cause denial-of-service. If the condition is not handled,
then it may or may not cause denial-of-service.
* Accessible From Unprivileged Processes:
Determine if the bug can be reached from a typical (non-root) user process that does NOT have any special capabilities
(like CAP_SYS_ADMIN, CAP_NET_ADMIN, CAP_NET_RAW, CAP_PERFMON) or access to device nodes restricted to root.
Assume that unprivileged_bpf_disabled=1, that is eBPF loading is not accessible. However, cBPF (classical BPF)
is still accessible to non-root processes.
Assume that user namespaces are not accessible, that is, the process cannot get the mentioned capabilities even
within a new user namespace (checked by ns_capable() function in the kernel sources).
* Accessible From User Namespaces:
Determine if the bug can be reached within a user-namespace where the process has all capabilities
(including CAP_SYS_ADMIN, CAP_NET_ADMIN, CAP_NET_RAW, CAP_PERFMON). Such capabilities are checked with ns_capable()
function in the kernel sources.
* VM Guest Trigger:
Determine if the bug can be triggered from the context of a typical KVM guest (e.g., set up by a QEMU VMM).
Consider accesses to standard Linux host paravirtualized features (virtio-blk, virtio-net, etc.),
and handling of VM exits in the KVM code.
* VM Host Trigger in The Confidential Computing Context:
Determine if the bug can be triggered in a confidential computing guest kernel from the context of a KVM host.
Consider access to standard Linux guest paravirtualized features (virtio-blk, virtio-net, etc.).
* Ethernet Network Trigger:
Determine if the bug can be triggered by processing ingress network Ethernet traffic, either directly (network stack)
or via drivers exposed to network data.
* Other Remote Trigger:
Determine if the bug can be triggered by processing remote traffic other than Ethernet (Wifi, Bluetooth, NFC, etc).
* Peripheral Trigger:
Determine if the bug can be triggered via an untrusted peripheral device that can be physically plugged
into a system, such as a USB device or a niche hardware driver handling external hardware inputs.
This is particularly important for mobile and desktop environments where users can plug in unknown devices.
* Malicious Filesystem Trigger:
Determine if the bug can be triggered by the kernel mounting and parsing a malicious filesystem image.
This is highly critical for Desktop and Mobile environments where external media or downloaded images
might be auto-mounted.
Don't make assumptions about the kernel source code (it may be different from what you assume it is).
Extensively use the provided code access tools (codesearch-*, git-*, grepper, etc)
to examine the actual source code, and confirm any assumptions.
Prefer calling several tools at the same time to save round-trips.
Use set-results tool to provide results of the analysis.
It must be called exactly once before the final reply.
Ignore results of this tool.
Prompt:
The kernel bug report is:
====================================
WARNING: syz.3.395/6091 still has locks held!
syzkaller #0 Not tainted
------------------------------------
1 lock held by syz.3.395/6091:
#0: ffff0000cf1b4258 (&devlink->lock_key#3){+.+.}-{4:4}, at: devl_lock+0x24/0x34 net/devlink/core.c:292
stack backtrace:
CPU: 1 UID: 0 PID: 6091 Comm: syz.3.395 Not tainted syzkaller #0 PREEMPT
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026
Call trace:
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
__dump_stack+0x30/0x40 lib/dump_stack.c:94
dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
dump_stack+0x1c/0x28 lib/dump_stack.c:129
print_held_locks_bug+0x90/0x98 kernel/locking/lockdep.c:6752
debug_check_no_locks_held+0x28/0x34 kernel/locking/lockdep.c:6760
try_to_freeze include/linux/freezer.h:62 [inline]
usermodehelper_read_trylock+0x1d8/0x294 kernel/umh.c:230
fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:147 [inline]
firmware_fallback_sysfs+0x158/0x918 drivers/base/firmware_loader/fallback.c:238
_request_firmware+0xb34/0xf5c drivers/base/firmware_loader/main.c:898
request_firmware+0x4c/0x70 drivers/base/firmware_loader/main.c:948
devlink_compat_flash_update+0x134/0x27c net/devlink/dev.c:1247
dev_ethtool+0x63c/0x1c40 net/ethtool/ioctl.c:3676
dev_ioctl+0x2a4/0xcf0 net/core/dev_ioctl.c:751
sock_do_ioctl+0x198/0x254 net/socket.c:1314
sock_ioctl+0x55c/0x7ec net/socket.c:1421
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__arm64_sys_ioctl+0x14c/0x1c4 fs/ioctl.c:583
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736
el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594
Reply: **Analysis of the Bug Report**
The bug report indicates a lockdep warning: `WARNING: syz.3.395/6091 still has locks held!`.
The stack trace shows that the warning is triggered during a firmware update operation via `devlink_compat_flash_update()`, which is called from the `dev_ethtool()` ioctl handler.
Here is the sequence of events leading to the warning:
1. `devlink_compat_flash_update()` acquires the devlink instance lock (`devl_lock(devlink)`).
2. It then calls `request_firmware()` to load the requested firmware file.
3. If the firmware is not found directly on the filesystem and the kernel is configured with `CONFIG_FW_LOADER_USER_HELPER_FALLBACK` (common in syzkaller/fuzzing kernels but typically disabled in production), the kernel falls back to triggering a user mode helper to load the firmware.
4. The user mode helper fallback mechanism calls `usermodehelper_read_trylock()`, which in turn calls `try_to_freeze()`.
5. `try_to_freeze()` checks if the current thread is holding any locks by calling `debug_check_no_locks_held()`. Since the devlink lock is held, lockdep emits a warning.
**Security Impact Assessment**
* **Exploitable:** No. This is purely a lockdep warning indicating a potential deadlock scenario if the system were to freeze (suspend/hibernate) while the lock is held. It does not cause memory corruption, out-of-bounds accesses, or information leaks.
* **Denial of Service:** No. In production kernels, `CONFIG_DEBUG_LOCK_ALLOC` (lockdep) is disabled, meaning `debug_check_no_locks_held()` is a no-op and the warning will not even be printed. Furthermore, even if the user mode helper fallback blocks the thread for the default 60-second timeout, the only lock held is the specific `devlink->lock_key`. This lock only serializes operations on that specific devlink device instance (e.g., a virtual `netdevsim` device created by the user) and does not block system-wide operations or other devices.
* **Accessible From Unprivileged Processes:** No. The `ETHTOOL_FLASHDEV` command is restricted and requires the caller to have the `CAP_NET_ADMIN` capability in the network namespace (enforced in `dev_ethtool_locked()`).
* **Accessible From User Namespaces:** Yes. An unprivileged user can create a new user namespace and a new network namespace, thereby gaining `CAP_NET_ADMIN` within that namespace. They can then instantiate a virtual device that supports devlink (like `netdevsim`) and trigger the firmware update path. However, as established, doing so only affects their own virtual device and has no security impact on the host system.
**Conclusion**
This is a known lockdep warning related to calling `request_firmware()` while holding a mutex. It is not a security vulnerability, cannot be exploited for privilege escalation or memory corruption, and does not cause a system-wide denial of service.
|
| 6/2 |
2026/07/31 01:15 |
llm |
expert |
0m
Model:
Tokens:
input: 6719
output: 26
thoughts: 546
Thoughts: **Debugging a Lock Deprivation in the Network Stack**
Okay, so I've got this bug report, "WARNING: syz.3.395/6091 still has locks held!" which, frankly, isn't something I want to see. The stack trace is pretty clear, pointing directly to a lockdep issue. Let's see... it looks like `print_held_locks_bug` triggered a warning, ultimately showing that a lock is being held. Digging into the stack, I see `try_to_freeze` involved, which is interesting, and then down into `usermodehelper_read_trylock`, and eventually landing at `devlink_compat_flash_update` in `net/devlink/dev.c`. This suggests that the firmware loading path, perhaps triggered by an ethtool ioctl via `dev_ethtool`, is the culprit.
Specifically, the lock being held is `(&devlink->lock_key#3)`. Now, I need to understand what's happening with that `devlink` lock during this firmware update. I'll need to look closely at `devlink_compat_flash_update`, particularly around line 1247. From what I can glean from the stack, it seems like a firmware update operation is failing or is interrupted somewhere, possibly during freezing, leaving the `devlink` lock held. Time to delve into the code and see what the interaction between freezing, firmware loading, and devlink locking is doing here, and why it's not releasing the lock correctly in this specific scenario. I need to figure out what's going wrong with the lock acquisition and release within the context of the firmware update flow.
|
| 7/2 |
2026/07/31 01:15 |
tool |
codesearch-definition-source |
0m
Args: map[Name:devlink_compat_flash_update]
Results: map[SourceCode:1231: int devlink_compat_flash_update(struct devlink *devlink, const char *file_name)
1232: {
1233: struct devlink_flash_update_params params = {};
1234: int ret;
1235:
1236: devl_lock(devlink);
1237: if (!devl_is_registered(devlink)) {
1238: ret = -ENODEV;
1239: goto out_unlock;
1240: }
1241:
1242: if (!devlink->ops->flash_update) {
1243: ret = -EOPNOTSUPP;
1244: goto out_unlock;
1245: }
1246:
1247: ret = request_firmware(¶ms.fw, file_name, devlink->dev);
1248: if (ret)
1249: goto out_unlock;
1250:
1251: devlink_flash_update_begin_notify(devlink);
1252: ret = devlink->ops->flash_update(devlink, ¶ms, NULL);
1253: devlink_flash_update_end_notify(devlink);
1254:
1255: release_firmware(params.fw);
1256: out_unlock:
1257: devl_unlock(devlink);
1258:
1259: return ret;
1260: }
SourceFile:net/devlink/dev.c]
|
| 8/2 |
2026/07/31 01:15 |
llm |
expert |
0m
Model:
Tokens:
input: 8098
output: 23
thoughts: 176
Thoughts: Okay, let me break this down.
**Locking, Firmware, and the Potential for Freezing: My Concerns**
Right, so I'm looking at this `devlink_compat_flash_update` function, and it immediately grabs `devl_lock(devlink)`. That's standard practice, but then it goes and calls `request_firmware`. Now, `request_firmware` is the trigger here. I know that `request_firmware` is where things can get dicey. Specifically, it has a path that goes through `firmware_fallback_sysfs`, which is where `usermodehelper_read_trylock` lives, and that in turn calls `try_to_freeze`. And that's where the red flag goes up. `try_to_freeze` calls `debug_check_no_locks_held`.
This is a well-understood gotcha. We shouldn't be calling `request_firmware` when we're holding a lock, especially if there's a possibility of a user-mode helper getting involved. The problem is that calling `try_to_freeze` whilst holding a lock is asking for trouble. It can very easily lead to a deadlock.
Wait a second, let me check where this `devlink_compat_flash_update` gets called from... Okay, it's called from `dev_ethtool` in `net/ethtool/ioctl.c`. That's important context.
|
| 9/2 |
2026/07/31 01:15 |
tool |
codesearch-definition-source |
0m
Args:
Results: map[SourceCode:3646: int dev_ethtool(struct net *net, struct ifreq *ifr, void __user *useraddr)
3647: {
3648: struct ethtool_devlink_compat *state;
3649: u32 ethcmd;
3650: int rc;
3651:
3652: if (copy_from_user(ðcmd, useraddr, sizeof(ethcmd)))
3653: return -EFAULT;
3654:
3655: state = kzalloc_obj(*state);
3656: if (!state)
3657: return -ENOMEM;
3658:
3659: switch (ethcmd) {
3660: case ETHTOOL_FLASHDEV:
3661: if (copy_from_user(&state->efl, useraddr, sizeof(state->efl))) {
3662: rc = -EFAULT;
3663: goto exit_free;
3664: }
3665: state->efl.data[ETHTOOL_FLASH_MAX_FILENAME - 1] = 0;
3666: break;
3667: }
3668:
3669: rc = __dev_ethtool(net, ifr, useraddr, ethcmd, state);
3670: if (rc)
3671: goto exit_free;
3672:
3673: switch (ethcmd) {
3674: case ETHTOOL_FLASHDEV:
3675: if (state->devlink)
3676: rc = devlink_compat_flash_update(state->devlink,
3677: state->efl.data);
3678: break;
3679: case ETHTOOL_GDRVINFO:
3680: if (state->devlink)
3681: devlink_compat_running_version(state->devlink,
3682: state->info.fw_version,
3683: sizeof(state->info.fw_version));
3684: if (copy_to_user(useraddr, &state->info, sizeof(state->info))) {
3685: rc = -EFAULT;
3686: goto exit_free;
3687: }
3688: break;
3689: }
3690:
3691: exit_free:
3692: if (state->devlink)
3693: devlink_put(state->devlink);
3694: kfree(state);
3695: return rc;
3696: }
SourceFile:net/ethtool/ioctl.c]
|
| 10/2 |
2026/07/31 01:15 |
llm |
expert |
0m
Model:
Tokens:
input: 9367
output: 21
thoughts: 54
Thoughts: **Investigating Potential Privilege Escalation via dev_ethtool**
Okay, hold on a second. I'm tracing the execution path and it looks like `dev_ethtool` is called from `dev_ioctl`, which is located in `net/core/dev_ioctl.c`. My immediate concern is whether or not `dev_ethtool` is accessible to unprivileged users. I need to figure out the permissions model on `dev_ioctl` to determine if this is a possible attack vector. Let's dig into the details of `dev_ioctl` and see what the access control logic looks like.
|
| 11/2 |
2026/07/31 01:15 |
tool |
codesearch-definition-source |
0m
Args:
Results: map[SourceCode: 699: int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr,
700: void __user *data, bool *need_copyout)
701: {
702: int ret;
703: char *colon;
704:
705: if (need_copyout)
706: *need_copyout = true;
707: if (cmd == SIOCGIFNAME)
708: return dev_ifname(net, ifr);
709:
710: ifr->ifr_name[IFNAMSIZ-1] = 0;
711:
712: colon = strchr(ifr->ifr_name, ':');
713: if (colon)
714: *colon = 0;
715:
716: /*
717: * See which interface the caller is talking about.
718: */
719:
720: switch (cmd) {
721: case SIOCGIFHWADDR:
722: dev_load(net, ifr->ifr_name);
723: ret = netif_get_mac_address(&ifr->ifr_hwaddr, net,
724: ifr->ifr_name);
725: if (colon)
726: *colon = ':';
727: return ret;
728: /*
729: * These ioctl calls:
730: * - can be done by all.
731: * - atomic and do not require locking.
732: * - return a value
733: */
734: case SIOCGIFFLAGS:
735: case SIOCGIFMETRIC:
736: case SIOCGIFMTU:
737: case SIOCGIFSLAVE:
738: case SIOCGIFMAP:
739: case SIOCGIFINDEX:
740: case SIOCGIFTXQLEN:
741: dev_load(net, ifr->ifr_name);
742: rcu_read_lock();
743: ret = dev_ifsioc_locked(net, ifr, cmd);
744: rcu_read_unlock();
745: if (colon)
746: *colon = ':';
747: return ret;
748:
749: case SIOCETHTOOL:
750: dev_load(net, ifr->ifr_name);
751: ret = dev_ethtool(net, ifr, data);
752: if (colon)
753: *colon = ':';
754: return ret;
755:
756: /*
757: * These ioctl calls:
758: * - require superuser power.
759: * - require strict serialization.
760: * - return a value
761: */
762: case SIOCGMIIPHY:
763: case SIOCGMIIREG:
764: case SIOCSIFNAME:
765: dev_load(net, ifr->ifr_name);
766: if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
767: return -EPERM;
768:
769: rtnl_net_lock(net);
770: ret = dev_ifsioc(net, ifr, data, cmd);
771: rtnl_net_unlock(net);
772:
773: if (colon)
774: *colon = ':';
775: return ret;
776:
777: /*
778: * These ioctl calls:
779: * - require superuser power.
780: * - require strict serialization.
781: * - do not return a value
782: */
783: case SIOCSIFMAP:
784: case SIOCSIFTXQLEN:
785: if (!capable(CAP_NET_ADMIN))
786: return -EPERM;
787: fallthrough;
788: /*
789: * These ioctl calls:
790: * - require local superuser power.
791: * - require strict serialization.
792: * - do not return a value
793: */
794: case SIOCSIFFLAGS:
795: case SIOCSIFMETRIC:
796: case SIOCSIFMTU:
797: case SIOCSIFHWADDR:
798: case SIOCSIFSLAVE:
799: case SIOCADDMULTI:
800: case SIOCDELMULTI:
801: case SIOCSIFHWBROADCAST:
802: case SIOCSMIIREG:
803: case SIOCBONDENSLAVE:
804: case SIOCBONDRELEASE:
805: case SIOCBONDSETHWADDR:
806: case SIOCBONDCHANGEACTIVE:
807: case SIOCSHWTSTAMP:
808: if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
809: return -EPERM;
810: fallthrough;
811: case SIOCBONDSLAVEINFOQUERY:
812: case SIOCBONDINFOQUERY:
813: dev_load(net, ifr->ifr_name);
814:
815: rtnl_net_lock(net);
816: ret = dev_ifsioc(net, ifr, data, cmd);
817: rtnl_net_unlock(net);
818:
819: if (need_copyout)
820: *need_copyout = false;
821: return ret;
822:
823: case SIOCGIFMEM:
824: /* Get the per device memory space. We can add this but
825: * currently do not support it */
826: case SIOCSIFMEM:
827: /* Set the per device memory buffer space.
828: * Not applicable in our case */
829: case SIOCSIFLINK:
830: return -ENOTTY;
831:
832: /*
833: * Unknown or private ioctl.
834: */
835: default:
836: if (cmd == SIOCWANDEV ||
837: cmd == SIOCGHWTSTAMP ||
838: (cmd >= SIOCDEVPRIVATE &&
839: cmd <= SIOCDEVPRIVATE + 15)) {
840: dev_load(net, ifr->ifr_name);
841:
842: rtnl_net_lock(net);
843: ret = dev_ifsioc(net, ifr, data, cmd);
844: rtnl_net_unlock(net);
845: return ret;
846: }
847: return -ENOTTY;
848: }
849: }
SourceFile:net/core/dev_ioctl.c]
|
| 12/2 |
2026/07/31 01:15 |
llm |
expert |
0m
Model:
Tokens:
input: 11672
output: 24
thoughts: 61
Thoughts: **Analyzing the SIOCETHTOOL Vulnerability**
Okay, so `dev_ioctl` is dealing with `SIOCETHTOOL`, and the code isn't doing any capability checks... that's a red flag. Hmm, let me check `dev_ethtool` within `net/ethtool/ioctl.c`. It looks like `dev_ethtool` calls `__dev_ethtool`. Alright, let's dive into `__dev_ethtool` and see what's going on there. I need to understand what's happening at that level to gauge the extent of this potential issue. I suspect this will be the heart of the problem if we have an uncontrolled access issue.
|
| 13/2 |
2026/07/31 01:15 |
tool |
codesearch-definition-source |
0m
Args:
Results: map[SourceCode:3609: static int
3610: __dev_ethtool(struct net *net, struct ifreq *ifr, void __user *useraddr,
3611: u32 ethcmd, struct ethtool_devlink_compat *devlink_state)
3612: {
3613: netdevice_tracker dev_tracker;
3614: struct net_device *dev;
3615: bool need_rtnl;
3616: int rc;
3617:
3618: dev = netdev_get_by_name(net, ifr->ifr_name, &dev_tracker, GFP_KERNEL);
3619: if (!dev)
3620: return -ENODEV;
3621:
3622: need_rtnl = !netdev_need_ops_lock(dev) ||
3623: ethtool_cmd_changes_features(ethcmd) ||
3624: ethtool_ioctl_needs_rtnl(dev, ethcmd);
3625: if (need_rtnl)
3626: rtnl_lock();
3627: netdev_lock_ops(dev);
3628: if (dev->reg_state > NETREG_REGISTERED ||
3629: dev->moving_ns || !net_eq(dev_net(dev), net)) {
3630: rc = -ENODEV;
3631: goto exit_ops_unlock;
3632: }
3633:
3634: rc = dev_ethtool_locked(net, dev, useraddr, ethcmd, devlink_state,
3635: need_rtnl);
3636:
3637: exit_ops_unlock:
3638: netdev_unlock_ops(dev);
3639: if (need_rtnl)
3640: rtnl_unlock();
3641: netdev_put(dev, &dev_tracker);
3642:
3643: return rc;
3644: }
SourceFile:net/ethtool/ioctl.c]
|
| 14/2 |
2026/07/31 01:15 |
llm |
expert |
0m
Model:
Tokens:
input: 12502
output: 25
thoughts: 13
Thoughts: Here's my attempt at summarizing the thought process, tailored for an expert audience and written in the first person:
**Checking `dev_ethtool_locked`**
Okay, so I need to quickly assess something. My initial thought is to dive straight into examining `dev_ethtool_locked`. I'm going to assume, based on the naming, that it's a key variable in controlling access or the state of ethtool operations on a device. My focus is going to be on understanding *why* I need to check it. Is this a common debugging step in a particular context? Am I expecting a lock contention issue? Or am I simply looking for the current state of the lock as a preliminary step to understand a potential problem? Knowing the context would greatly assist in assessing the significance of this variable. The subsequent action I take will depend heavily on the reason for the inspection. I'll need to remember the architectural context - is this kernel-space, userspace, or something else entirely? The type of this variable, the functions which use it, and the locking mechanism in use (mutex, spinlock, etc.) are all relevant pieces of information that I'll need to keep in mind as I begin to trace through the code.
|
| 15/2 |
2026/07/31 01:15 |
tool |
codesearch-definition-source |
0m
Args: map[Name:dev_ethtool_locked]
Results: map[SourceCode:3271: static int
3272: dev_ethtool_locked(struct net *net, struct net_device *dev,
3273: void __user *useraddr,
3274: u32 ethcmd, struct ethtool_devlink_compat *devlink_state,
3275: bool has_rtnl_lock)
3276: {
3277: u32 sub_cmd;
3278: int rc;
3279: netdev_features_t old_features;
3280:
3281: if (ethcmd == ETHTOOL_PERQUEUE) {
3282: if (copy_from_user(&sub_cmd, useraddr + sizeof(ethcmd), sizeof(sub_cmd)))
3283: return -EFAULT;
3284: } else {
3285: sub_cmd = ethcmd;
3286: }
3287: /* Allow some commands to be done by anyone */
3288: switch (sub_cmd) {
3289: case ETHTOOL_GSET:
3290: case ETHTOOL_GDRVINFO:
3291: case ETHTOOL_GMSGLVL:
3292: case ETHTOOL_GLINK:
3293: case ETHTOOL_GCOALESCE:
3294: case ETHTOOL_GRINGPARAM:
3295: case ETHTOOL_GPAUSEPARAM:
3296: case ETHTOOL_GRXCSUM:
3297: case ETHTOOL_GTXCSUM:
3298: case ETHTOOL_GSG:
3299: case ETHTOOL_GSSET_INFO:
3300: case ETHTOOL_GSTRINGS:
3301: case ETHTOOL_GSTATS:
3302: case ETHTOOL_GPHYSTATS:
3303: case ETHTOOL_GTSO:
3304: case ETHTOOL_GPERMADDR:
3305: case ETHTOOL_GUFO:
3306: case ETHTOOL_GGSO:
3307: case ETHTOOL_GGRO:
3308: case ETHTOOL_GFLAGS:
3309: case ETHTOOL_GPFLAGS:
3310: case ETHTOOL_GRXFH:
3311: case ETHTOOL_GRXRINGS:
3312: case ETHTOOL_GRXCLSRLCNT:
3313: case ETHTOOL_GRXCLSRULE:
3314: case ETHTOOL_GRXCLSRLALL:
3315: case ETHTOOL_GRXFHINDIR:
3316: case ETHTOOL_GRSSH:
3317: case ETHTOOL_GFEATURES:
3318: case ETHTOOL_GCHANNELS:
3319: case ETHTOOL_GET_TS_INFO:
3320: case ETHTOOL_GEEE:
3321: case ETHTOOL_GTUNABLE:
3322: case ETHTOOL_PHY_GTUNABLE:
3323: case ETHTOOL_GLINKSETTINGS:
3324: case ETHTOOL_GFECPARAM:
3325: break;
3326: default:
3327: if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3328: return -EPERM;
3329: }
3330:
3331: netdev_assert_locked_ops_compat(dev);
3332:
3333: if (dev->dev.parent)
3334: pm_runtime_get_sync(dev->dev.parent);
3335:
3336: if (!netif_device_present(dev)) {
3337: rc = -ENODEV;
3338: goto out;
3339: }
3340:
3341: if (dev->ethtool_ops->begin) {
3342: rc = dev->ethtool_ops->begin(dev);
3343: if (rc < 0)
3344: goto out;
3345: }
3346: old_features = dev->features;
3347:
3348: switch (ethcmd) {
3349: case ETHTOOL_GSET:
3350: rc = ethtool_get_settings(dev, useraddr);
3351: break;
3352: case ETHTOOL_SSET:
3353: rc = ethtool_set_settings(dev, useraddr);
3354: break;
3355: case ETHTOOL_GDRVINFO:
3356: rc = ethtool_get_drvinfo(dev, devlink_state);
3357: break;
3358: case ETHTOOL_GREGS:
3359: rc = ethtool_get_regs(dev, useraddr);
3360: break;
3361: case ETHTOOL_GWOL:
3362: rc = ethtool_get_wol(dev, useraddr);
3363: break;
3364: case ETHTOOL_SWOL:
3365: rc = ethtool_set_wol(dev, useraddr);
3366: break;
3367: case ETHTOOL_GMSGLVL:
3368: rc = ethtool_get_value(dev, useraddr, ethcmd,
3369: dev->ethtool_ops->get_msglevel);
3370: break;
3371: case ETHTOOL_SMSGLVL:
3372: rc = ethtool_set_value_void(dev, useraddr,
3373: dev->ethtool_ops->set_msglevel);
3374: if (!rc)
3375: ethtool_notify(dev, ETHTOOL_MSG_DEBUG_NTF);
3376: break;
3377: case ETHTOOL_GEEE:
3378: rc = ethtool_get_eee(dev, useraddr);
3379: break;
3380: case ETHTOOL_SEEE:
3381: rc = ethtool_set_eee(dev, useraddr);
3382: break;
3383: case ETHTOOL_NWAY_RST:
3384: rc = ethtool_nway_reset(dev);
3385: break;
3386: case ETHTOOL_GLINK:
3387: rc = ethtool_get_link(dev, useraddr);
3388: break;
3389: case ETHTOOL_GEEPROM:
3390: rc = ethtool_get_eeprom(dev, useraddr);
3391: break;
3392: case ETHTOOL_SEEPROM:
3393: rc = ethtool_set_eeprom(dev, useraddr);
3394: break;
3395: case ETHTOOL_GCOALESCE:
3396: rc = ethtool_get_coalesce(dev, useraddr);
3397: break;
3398: case ETHTOOL_SCOALESCE:
3399: rc = ethtool_set_coalesce(dev, useraddr);
3400: break;
3401: case ETHTOOL_GRINGPARAM:
3402: rc = ethtool_get_ringparam(dev, useraddr);
3403: break;
3404: case ETHTOOL_SRINGPARAM:
3405: rc = ethtool_set_ringparam(dev, useraddr);
3406: break;
3407: case ETHTOOL_GPAUSEPARAM:
3408: rc = ethtool_get_pauseparam(dev, useraddr);
3409: break;
3410: case ETHTOOL_SPAUSEPARAM:
3411: rc = ethtool_set_pauseparam(dev, useraddr);
3412: break;
3413: case ETHTOOL_TEST:
3414: rc = ethtool_self_test(dev, useraddr);
3415: break;
3416: case ETHTOOL_GSTRINGS:
3417: rc = ethtool_get_strings(dev, useraddr);
3418: break;
3419: case ETHTOOL_PHYS_ID:
3420: rc = ethtool_phys_id(dev, useraddr, has_rtnl_lock);
3421: break;
3422: case ETHTOOL_GSTATS:
3423: rc = ethtool_get_stats(dev, useraddr);
3424: break;
3425: case ETHTOOL_GPERMADDR:
3426: rc = ethtool_get_perm_addr(dev, useraddr);
3427: break;
3428: case ETHTOOL_GFLAGS:
3429: rc = ethtool_get_value(dev, useraddr, ethcmd,
3430: __ethtool_get_flags);
3431: break;
3432: case ETHTOOL_SFLAGS:
3433: rc = ethtool_set_value(dev, useraddr, __ethtool_set_flags);
3434: break;
3435: case ETHTOOL_GPFLAGS:
3436: rc = ethtool_get_value(dev, useraddr, ethcmd,
3437: dev->ethtool_ops->get_priv_flags);
3438: if (!rc)
3439: ethtool_notify(dev, ETHTOOL_MSG_PRIVFLAGS_NTF);
3440: break;
3441: case ETHTOOL_SPFLAGS:
3442: rc = ethtool_set_value(dev, useraddr,
3443: dev->ethtool_ops->set_priv_flags);
3444: break;
3445: case ETHTOOL_GRXFH:
3446: rc = ethtool_get_rxfh_fields(dev, ethcmd, useraddr);
3447: break;
3448: case ETHTOOL_SRXFH:
3449: rc = ethtool_set_rxfh_fields(dev, ethcmd, useraddr);
3450: break;
3451: case ETHTOOL_GRXRINGS:
3452: rc = ethtool_get_rxrings(dev, ethcmd, useraddr);
3453: break;
3454: case ETHTOOL_GRXCLSRLCNT:
3455: case ETHTOOL_GRXCLSRULE:
3456: case ETHTOOL_GRXCLSRLALL:
3457: rc = ethtool_get_rxnfc(dev, ethcmd, useraddr);
3458: break;
3459: case ETHTOOL_SRXCLSRLDEL:
3460: case ETHTOOL_SRXCLSRLINS:
3461: rc = ethtool_set_rxnfc(dev, ethcmd, useraddr);
3462: break;
3463: case ETHTOOL_FLASHDEV:
3464: rc = ethtool_flash_device(dev, devlink_state);
3465: break;
3466: case ETHTOOL_RESET:
3467: rc = ethtool_reset(dev, useraddr);
3468: break;
3469: case ETHTOOL_GSSET_INFO:
3470: rc = ethtool_get_sset_info(dev, useraddr);
3471: break;
3472: case ETHTOOL_GRXFHINDIR:
3473: rc = ethtool_get_rxfh_indir(dev, useraddr);
3474: break;
3475: case ETHTOOL_SRXFHINDIR:
3476: rc = ethtool_set_rxfh_indir(dev, useraddr);
3477: break;
3478: case ETHTOOL_GRSSH:
3479: rc = ethtool_get_rxfh(dev, useraddr);
3480: break;
3481: case ETHTOOL_SRSSH:
3482: rc = ethtool_set_rxfh(dev, useraddr);
3483: break;
3484: case ETHTOOL_GFEATURES:
3485: rc = ethtool_get_features(dev, useraddr);
3486: break;
3487: case ETHTOOL_SFEATURES:
3488: rc = ethtool_set_features(dev, useraddr);
3489: break;
3490: case ETHTOOL_GTXCSUM:
3491: case ETHTOOL_GRXCSUM:
3492: case ETHTOOL_GSG:
3493: case ETHTOOL_GTSO:
3494: case ETHTOOL_GGSO:
3495: case ETHTOOL_GGRO:
3496: rc = ethtool_get_one_feature(dev, useraddr, ethcmd);
3497: break;
3498: case ETHTOOL_STXCSUM:
3499: case ETHTOOL_SRXCSUM:
3500: case ETHTOOL_SSG:
3501: case ETHTOOL_STSO:
3502: case ETHTOOL_SGSO:
3503: case ETHTOOL_SGRO:
3504: rc = ethtool_set_one_feature(dev, useraddr, ethcmd);
3505: break;
3506: case ETHTOOL_GCHANNELS:
3507: rc = ethtool_get_channels(dev, useraddr);
3508: break;
3509: case ETHTOOL_SCHANNELS:
3510: rc = ethtool_set_channels(dev, useraddr);
3511: break;
3512: case ETHTOOL_SET_DUMP:
3513: rc = ethtool_set_dump(dev, useraddr);
3514: break;
3515: case ETHTOOL_GET_DUMP_FLAG:
3516: rc = ethtool_get_dump_flag(dev, useraddr);
3517: break;
3518: case ETHTOOL_GET_DUMP_DATA:
3519: rc = ethtool_get_dump_data(dev, useraddr);
3520: break;
3521: case ETHTOOL_GET_TS_INFO:
3522: rc = ethtool_get_ts_info(dev, useraddr);
3523: break;
3524: case ETHTOOL_GMODULEINFO:
3525: rc = ethtool_get_module_info(dev, useraddr);
3526: break;
3527: case ETHTOOL_GMODULEEEPROM:
3528: rc = ethtool_get_module_eeprom(dev, useraddr);
3529: break;
3530: case ETHTOOL_GTUNABLE:
3531: rc = ethtool_get_tunable(dev, useraddr);
3532: break;
3533: case ETHTOOL_STUNABLE:
3534: rc = ethtool_set_tunable(dev, useraddr);
3535: break;
3536: case ETHTOOL_GPHYSTATS:
3537: rc = ethtool_get_phy_stats(dev, useraddr);
3538: break;
3539: case ETHTOOL_PERQUEUE:
3540: rc = ethtool_set_per_queue(dev, useraddr, sub_cmd);
3541: break;
3542: case ETHTOOL_GLINKSETTINGS:
3543: rc = ethtool_get_link_ksettings(dev, useraddr);
3544: break;
3545: case ETHTOOL_SLINKSETTINGS:
3546: rc = ethtool_set_link_ksettings(dev, useraddr);
3547: break;
3548: case ETHTOOL_PHY_GTUNABLE:
3549: rc = get_phy_tunable(dev, useraddr);
3550: break;
3551: case ETHTOOL_PHY_STUNABLE:
3552: rc = set_phy_tunable(dev, useraddr);
3553: break;
3554: case ETHTOOL_GFECPARAM:
3555: rc = ethtool_get_fecparam(dev, useraddr);
3556: break;
3557: case ETHTOOL_SFECPARAM:
3558: rc = ethtool_set_fecparam(dev, useraddr);
3559: break;
3560: default:
3561: rc = -EOPNOTSUPP;
3562: }
3563:
3564: if (dev->ethtool_ops->complete)
3565: dev->ethtool_ops->complete(dev);
3566:
3567: switch (ethcmd) {
3568: case ETHTOOL_PHYS_ID:
3569: /* Don't check features if operation drops the locks.
3570: * Someone else may have changed features in parallel.
3571: */
3572: break;
3573: default:
3574: if (old_features != dev->features) {
3575: if (has_rtnl_lock)
3576: netdev_features_change(dev);
3577: else
3578: netdev_WARN(dev, "ethtool cmd %u changed features without rtnl_lock", ethcmd);
3579: }
3580: }
3581: out:
3582: if (dev->dev.parent)
3583: pm_runtime_put(dev->dev.parent);
3584:
3585: return rc;
3586: }
SourceFile:net/ethtool/ioctl.c]
|
| 16/2 |
2026/07/31 01:15 |
llm |
expert |
0m
Model:
Tokens:
input: 17840
output: 21
thoughts: 1265
Thoughts: **Analyzing a Potential Deadlock in devlink Firmware Update**
Okay, let's break this down. My initial thought is that `ETHTOOL_FLASHDEV`, which corresponds to a firmware update operation, requires `CAP_NET_ADMIN` within the network namespace. That's fine; it's a controlled operation. Since this operation is namespaced it can be accessed from user namespaces if the user creates both a user namespace and a network namespace.
Then, there's this `lockdep` warning: "WARNING: syz.3.395/6091 still has locks held!" I know lockdep warnings aren't fatal in a production kernel, but they scream potential deadlock. The core concern seems to revolve around `request_firmware`, which potentially triggers a user-mode helper. If this helper then tries to acquire the same `devlink->lock_key`, which is now held from the initial operation, a deadlock is possible.
However, after considering it, the user-mode helper is for firmware loading and doesn't *normally* interact with devlink's internal locks. The helper loads generic firmware. That's a relief. It seems less likely a direct lock conflict is the problem.
But the plot thickens... `try_to_freeze` calls `debug_check_no_locks_held()`. During a system freeze (suspend/hibernate), this check warns if a lock is held, which is what we see here. However, in production builds this warning is stripped out because `CONFIG_DEBUG_LOCK_ALLOC` is disabled, so the call becomes a no-op, which means there is no warning in production builds.
So, while the warning is not present in production builds, if a thread is blocked in `request_firmware` holding the devlink lock, a deadlock is possible if the system tries to freeze, and another thread which *isn't* frozen (e.g. a kernel thread with `PF_NOFREEZE`) then tries to acquire the same devlink lock. The devlink lock is usually accessed by user-space triggered operations or specific driver operations.
Is this exploitable? Probably not. It's more of a denial-of-service vulnerability.
The real DoS comes in. `request_firmware` with `firmware_fallback_sysfs` can wait for a *timeout* (60 seconds, typically) if the firmware is missing. During this entire timeout, the `devlink` lock will be held. The user must be in a network namespace, but a standard user can create their own namespace to trigger this vulnerability, and hold a devlink lock for a significant amount of time, preventing other devlink operations on *that* specific device.
The interesting question is how a normal user could trigger a firmware update operation that is in a new network namespace. The device must be present in the new network namespace. A user could create a virtual device such as `veth` or use `netdevsim` or `dummy` devices. It's likely `netdevsim` is a good candidate since `netdevsim` supports devlink. I need to verify whether `netdevsim` supports `flash_update`.
|
| 17/2 |
2026/07/31 01:16 |
tool |
codesearch-find-references |
0m
Error:
Args:
Results: map[References:<nil> TruncatedOutput:false]
|
| 18/2 |
2026/07/31 01:16 |
llm |
expert |
0m
Model:
Tokens:
input: 19824
output: 26
thoughts: 18
Thoughts: Okay, here's my interpretation of that thought process, tailored for an expert audience, and written in the first person:
**Decoding `devlink_ops` and `flash_update`**
Right, so I'm seeing this `flash_update` thing, and it's popping up as a field within the `struct devlink_ops`. My initial thought is to immediately place this within the devlink framework context. I know this structure is fundamental to how we manage and expose device-specific operations related to, well, links and connectivity, especially in more advanced devices. The name itself, `flash_update`, strongly suggests we're dealing with something related to updating firmware or non-volatile memory on the device. Given the context, it's pretty clear this is a pointer to a function within those device operations. It means that to update the flash of the device, you would call the function provided in this field, from the `devlink_ops` structure. This likely involves handling various aspects such as image loading, addressing concerns (partitioning, offset), error checking, and progress reporting, considering the device's hardware constraints. This function, I assume, encapsulates all the device-specific complexities involved in a flash update, providing a uniform API on the kernel side. Now, I'm thinking about the implications on error handling, security, and potential concurrent access issues. Good, I'll keep thinking on that.
|
| 19/2 |
2026/07/31 01:16 |
tool |
codesearch-find-references |
0m
Args: map[Name:devlink_ops::flash_update]
Results: map[References:[map[ReferenceKind:reads ReferencingEntityKind:function ReferencingEntityName:devlink_compat_flash_update SourceFile:net/devlink/dev.c SourceLine:1242] map[ReferenceKind:reads ReferencingEntityKind:function ReferencingEntityName:devlink_compat_flash_update SourceFile:net/devlink/dev.c SourceLine:1252] map[ReferenceKind:reads ReferencingEntityKind:function ReferencingEntityName:devlink_nl_flash_update_doit SourceFile:net/devlink/dev.c SourceLine:1142] map[ReferenceKind:reads ReferencingEntityKind:function ReferencingEntityName:devlink_nl_flash_update_doit SourceFile:net/devlink/dev.c SourceLine:1179]] TruncatedOutput:false]
|
| 20/2 |
2026/07/31 01:16 |
llm |
expert |
0m
Model:
Tokens:
input: 20407
output: 21
thoughts: 22
Thoughts: Here's my thought process, as if I were considering this myself:
**Investigating `struct devlink_ops` and `flash_update` Initialization**
Okay, so I need to find out where and how `flash_update` is being initialized within the context of `struct devlink_ops`. My initial instinct is to delve directly into the kernel source, specifically looking for definitions of `struct devlink_ops`. I know this is a key structure for managing device links, so understanding the interactions within is important. I'm going to start by searching the code for instances where `struct devlink_ops` is defined or declared, with a specific focus on seeing if and how the `flash_update` member is addressed. I'll need to pay close attention to the initialization patterns, like the use of compound literals or any helper macros that might be employed. I want to see which drivers are setting this particular operation and under what circumstances, as this will illuminate its intended usage. It's likely involved in firmware updates, so I expect the code surrounding it to be related to that functionality. My next step will be tracking down any calls to that function pointer, to understand how it's *used* once set up. I'll expect to look for any checks on its validity before it is called as well. This should give me a pretty comprehensive picture of the whole situation.
|
| 21/2 |
2026/07/31 01:16 |
tool |
grepper |
0m
Args: map[Expression:\.flash_update\s*=]
Results: map[Output:drivers/dpll/zl3073x/devlink.c=271=static const struct devlink_ops zl3073x_devlink_ops = {
--
drivers/dpll/zl3073x/devlink.c-275- .reload_up = zl3073x_devlink_reload_up,
drivers/dpll/zl3073x/devlink.c:276: .flash_update = zl3073x_devlink_flash_update,
drivers/dpll/zl3073x/devlink.c-277-};
--
drivers/net/ethernet/amd/pds_core/main.c=322=static const struct devlink_ops pdsc_dl_ops = {
drivers/net/ethernet/amd/pds_core/main.c-323- .info_get = pdsc_dl_info_get,
drivers/net/ethernet/amd/pds_core/main.c:324: .flash_update = pdsc_dl_flash_update,
drivers/net/ethernet/amd/pds_core/main.c-325-};
--
drivers/net/ethernet/broadcom/bnxt/bnxt_devlink.c=644=static const struct devlink_ops bnxt_dl_ops = {
--
drivers/net/ethernet/broadcom/bnxt/bnxt_devlink.c-649- .info_get = bnxt_dl_info_get,
drivers/net/ethernet/broadcom/bnxt/bnxt_devlink.c:650: .flash_update = bnxt_dl_flash_update,
drivers/net/ethernet/broadcom/bnxt/bnxt_devlink.c-651- .reload_actions = BIT(DEVLINK_RELOAD_ACTION_DRIVER_REINIT) |
--
drivers/net/ethernet/huawei/hinic/hinic_devlink.c=290=static const struct devlink_ops hinic_devlink_ops = {
drivers/net/ethernet/huawei/hinic/hinic_devlink.c:291: .flash_update = hinic_devlink_flash_update,
drivers/net/ethernet/huawei/hinic/hinic_devlink.c-292-};
--
drivers/net/ethernet/intel/ice/devlink/devlink.c=1323=static const struct devlink_ops ice_devlink_ops = {
--
drivers/net/ethernet/intel/ice/devlink/devlink.c-1331- .info_get = ice_devlink_info_get,
drivers/net/ethernet/intel/ice/devlink/devlink.c:1332: .flash_update = ice_devlink_flash_update,
drivers/net/ethernet/intel/ice/devlink/devlink.c-1333-
--
drivers/net/ethernet/intel/ixgbe/devlink/devlink.c=480=static const struct devlink_ops ixgbe_devlink_ops = {
--
drivers/net/ethernet/intel/ixgbe/devlink/devlink.c-483- DEVLINK_SUPPORT_FLASH_UPDATE_OVERWRITE_MASK,
drivers/net/ethernet/intel/ixgbe/devlink/devlink.c:484: .flash_update = ixgbe_flash_pldm_image,
drivers/net/ethernet/intel/ixgbe/devlink/devlink.c-485- .reload_actions = BIT(DEVLINK_RELOAD_ACTION_FW_ACTIVATE),
--
drivers/net/ethernet/mellanox/mlx5/core/devlink.c=368=static const struct devlink_ops mlx5_devlink_ops = {
--
drivers/net/ethernet/mellanox/mlx5/core/devlink.c-389-#endif
drivers/net/ethernet/mellanox/mlx5/core/devlink.c:390: .flash_update = mlx5_devlink_flash_update,
drivers/net/ethernet/mellanox/mlx5/core/devlink.c-391- .info_get = mlx5_devlink_info_get,
--
drivers/net/ethernet/mellanox/mlxsw/core.c=1734=static const struct devlink_ops mlxsw_devlink_ops = {
--
drivers/net/ethernet/mellanox/mlxsw/core.c-1749- .info_get = mlxsw_devlink_info_get,
drivers/net/ethernet/mellanox/mlxsw/core.c:1750: .flash_update = mlxsw_devlink_flash_update,
drivers/net/ethernet/mellanox/mlxsw/core.c-1751- .trap_init = mlxsw_devlink_trap_init,
--
drivers/net/ethernet/mellanox/mlxsw/core_linecard_dev.c=122=static const struct devlink_ops mlxsw_linecard_dev_devlink_ops = {
drivers/net/ethernet/mellanox/mlxsw/core_linecard_dev.c-123- .info_get = mlxsw_linecard_dev_devlink_info_get,
drivers/net/ethernet/mellanox/mlxsw/core_linecard_dev.c:124: .flash_update = mlxsw_linecard_dev_devlink_flash_update,
drivers/net/ethernet/mellanox/mlxsw/core_linecard_dev.c-125-};
--
drivers/net/ethernet/meta/fbnic/fbnic_devlink.c=368=static const struct devlink_ops fbnic_devlink_ops = {
drivers/net/ethernet/meta/fbnic/fbnic_devlink.c-369- .info_get = fbnic_devlink_info_get,
drivers/net/ethernet/meta/fbnic/fbnic_devlink.c:370: .flash_update = fbnic_devlink_flash_update,
drivers/net/ethernet/meta/fbnic/fbnic_devlink.c-371-};
--
drivers/net/ethernet/netronome/nfp/nfp_devlink.c=318=const struct devlink_ops nfp_devlink_ops = {
--
drivers/net/ethernet/netronome/nfp/nfp_devlink.c-323- .info_get = nfp_devlink_info_get,
drivers/net/ethernet/netronome/nfp/nfp_devlink.c:324: .flash_update = nfp_devlink_flash_update,
drivers/net/ethernet/netronome/nfp/nfp_devlink.c-325-};
--
drivers/net/ethernet/pensando/ionic/ionic_devlink.c=54=static const struct devlink_ops ionic_dl_ops = {
drivers/net/ethernet/pensando/ionic/ionic_devlink.c-55- .info_get = ionic_dl_info_get,
drivers/net/ethernet/pensando/ionic/ionic_devlink.c:56: .flash_update = ionic_dl_flash_update,
drivers/net/ethernet/pensando/ionic/ionic_devlink.c-57-};
--
drivers/net/ethernet/sfc/efx_devlink.c=629=static const struct devlink_ops sfc_devlink_ops = {
drivers/net/ethernet/sfc/efx_devlink.c-630- .supported_flash_update_params = 0,
drivers/net/ethernet/sfc/efx_devlink.c:631: .flash_update = efx_devlink_flash_update,
drivers/net/ethernet/sfc/efx_devlink.c-632- .info_get = efx_devlink_info_get,
--
drivers/net/netdevsim/dev.c=1425=static const struct devlink_ops nsim_dev_devlink_ops = {
--
drivers/net/netdevsim/dev.c-1432- .info_get = nsim_dev_info_get,
drivers/net/netdevsim/dev.c:1433: .flash_update = nsim_dev_flash_update,
drivers/net/netdevsim/dev.c-1434- .trap_init = nsim_dev_devlink_trap_init,
--
drivers/net/wwan/iosm/iosm_ipc_devlink.c=137=static const struct devlink_ops devlink_flash_ops = {
drivers/net/wwan/iosm/iosm_ipc_devlink.c:138: .flash_update = ipc_devlink_flash_update,
drivers/net/wwan/iosm/iosm_ipc_devlink.c-139-};
--
drivers/ptp/ptp_ocp.c=2189=static const struct devlink_ops ptp_ocp_devlink_ops = {
drivers/ptp/ptp_ocp.c:2190: .flash_update = ptp_ocp_devlink_flash_update,
drivers/ptp/ptp_ocp.c-2191- .info_get = ptp_ocp_devlink_info_get,
]
|
| 22/2 |
2026/07/31 01:16 |
llm |
expert |
0m
Model:
Tokens:
input: 23157
output: 25
thoughts: 688
Thoughts: **Analyzing the netdevsim flash_update vulnerability**
Okay, so `netdevsim` supports `flash_update`, which is interesting. And, importantly, an unprivileged user can instantiate it, provided they have `CAP_NET_ADMIN` in a user namespace. Since `netdevsim` is a module, I need to check if it's loaded by default, but Syzkaller commonly handles this.
The immediate concern is the lockdep warning: `WARNING: syz.3.395/6091 still has locks held!`. This is generated by `debug_check_no_locks_held()`, which, fortunately, is a no-op in production kernels because `CONFIG_DEBUG_LOCK_ALLOC` isn't enabled. So, no immediate impact there.
However, if a user calls `ETHTOOL_FLASHDEV` on a `netdevsim` device, it triggers `request_firmware`, which might invoke the user mode helper. This helper waits for firmware, and *that* wait holds the `devlink->lock_key`. Is that a problem?
The `devlink` lock is specific to the `netdevsim` instance. It doesn't block other devices or the system, only devlink operations on *that* `netdevsim` device. Since the user created it, blocking their own device shouldn't cause widespread issues.
But what if the user mode helper *itself* needs a lock? No, the helper executes something like `/lib/udev/firmware.agent` and shouldn't be vying for the `devlink` lock.
And if the user mode helper isn't present? Then `request_firmware` times out after 60 seconds. While the thread is sleeping with the lock held. Is that an issue? Mutexes are designed to be held during sleep. The real problem is if the system tries to freeze (suspend/hibernate). The freezing process will call `try_to_freeze` on this thread.
If the thread is holding a lock when it calls `try_to_freeze`, it might freeze with the lock held. Then another thread, perhaps a kernel thread that hasn't frozen, could try to acquire this lock, which could lead to a deadlock. But the lock is `devlink->lock_key`, which is only used for devlink operations on *this* specific device. No *kernel* thread should try to acquire this lock during suspend/resume, *unless* the driver's suspend/resume callbacks touch it. Now I need to check if the `netdevsim` suspend/resume callbacks acquire the `devlink` lock. That's the crucial question.
|
| 23/2 |
2026/07/31 01:16 |
tool |
codesearch-find-references |
0m
Error:
Args: map[Name:nsim_dev_suspend]
Results: map[References:<nil> TruncatedOutput:false]
|
| 24/2 |
2026/07/31 01:16 |
llm |
expert |
0m
Model:
Tokens:
input: 24462
output: 19
thoughts: 17
Thoughts: Okay, here's my summary, presented as a direct, internal thought process:
**Investigating `netdevsim`'s Suspend/Resume Capabilities**
Alright, before I dive too deep into this, I need to make a quick check. The first thing that comes to mind is: does the `netdevsim` driver actually implement any suspend and resume callbacks? I need to know if it's even *designed* to handle power management events. If it doesn't, then any further investigation along those lines is a complete waste of time. Time to find the source code and confirm or deny. Let's see what we can find.
|
| 25/2 |
2026/07/31 01:16 |
tool |
grepper |
0m
Error:
Args: map[Expression:suspend.*nsim]
Results:
|
| 26/2 |
2026/07/31 01:16 |
llm |
expert |
0m
Model:
Tokens:
input: 24649
output: 23
thoughts: 492
Thoughts: **Analyzing the Security Implications of `netdevsim` and Firmware Loading**
Okay, so `netdevsim` doesn't implement suspend/resume callbacks. Fine, but what about the actual hardware drivers like `mlx5`, `ice`, `bnxt`, `ixgbe`? Those are the real targets here. To trigger `ETHTOOL_FLASHDEV` on a real device, you need `CAP_NET_ADMIN` in the network namespace where the device lives. Real hardware is usually in the initial namespace, meaning you need root access. If root does it, it's not a security issue, root can do anything. And if an unprivileged user triggers it with `netdevsim` in a user namespace, it's contained within their instance, no impact on the rest of the system.
But wait... are there *other* attack vectors? I need to think this through. The warning is just a lockdep warning, which isn't exploitable. No memory corruption, no information leak. Could it be a denial-of-service? Well, if an unprivileged user can trigger a 60-second kernel sleep, they can create threads to do it. But that's equivalent to calling `sleep(60)` in user space, so that's not interesting.
Ah, `request_firmware` allocates memory and uses system resources. However, it's rate-limited, and the number of threads is bounded. Actually, I need to look closer. `request_firmware` from a user namespace might not even trigger the user mode helper if it's disabled or if the firmware is not found directly.
Hang on. What about the `firmware_fallback_sysfs` path? That's only used if direct firmware loading fails. That path creates a sysfs device and waits for udev to load the firmware. Crucially, the sysfs device is created in the *initial* network namespace, since sysfs isn't network namespace aware.
Wait a second... *if* an unprivileged user can trigger `firmware_fallback_sysfs`, they can create sysfs devices in the initial namespace! That's a potential vulnerability. Now I need to check if `firmware_fallback_sysfs` is allowed from user namespaces. Time to dive into `_request_firmware`.
|
| 27/2 |
2026/07/31 01:16 |
tool |
codesearch-definition-source |
0m
Args: map[Name:_request_firmware]
Results: map[SourceCode: 825: /* called from request_firmware() and request_firmware_work_func() */
826: static int
827: _request_firmware(const struct firmware **firmware_p, const char *name,
828: struct device *device, void *buf, size_t size,
829: size_t offset, u32 opt_flags)
830: {
831: struct firmware *fw = NULL;
832: bool nondirect = false;
833: int ret;
834:
835: if (!firmware_p)
836: return -EINVAL;
837:
838: if (!name || name[0] == '\0') {
839: ret = -EINVAL;
840: goto out;
841: }
842:
843:
844: /*
845: * Reject firmware file names with ".." path components.
846: * There are drivers that construct firmware file names from
847: * device-supplied strings, and we don't want some device to be
848: * able to tell us "I would like to be sent my firmware from
849: * ../../../etc/shadow, please".
850: *
851: * This intentionally only looks at the firmware name, not at
852: * the firmware base directory or at symlink contents.
853: */
854: if (name_contains_dotdot(name)) {
855: dev_warn(device,
856: "Firmware load for '%s' refused, path contains '..' component\n",
857: name);
858: ret = -EINVAL;
859: goto out;
860: }
861:
862: ret = _request_firmware_prepare(&fw, name, device, buf, size,
863: offset, opt_flags);
864: if (ret <= 0) /* error or already assigned */
865: goto out;
866:
867: /*
868: * We are about to try to access the firmware file. Because we may have been
869: * called by a driver when serving an unrelated request from userland, we use
870: * the kernel credentials to read the file.
871: */
872: scoped_with_kernel_creds() {
873: ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
874:
875: /* Only full reads can support decompression, platform, and sysfs. */
876: if (!(opt_flags & FW_OPT_PARTIAL))
877: nondirect = true;
878:
879: #ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
880: if (ret == -ENOENT && nondirect)
881: ret = fw_get_filesystem_firmware(device, fw->priv, ".zst",
882: fw_decompress_zstd);
883: #endif
884: #ifdef CONFIG_FW_LOADER_COMPRESS_XZ
885: if (ret == -ENOENT && nondirect)
886: ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
887: fw_decompress_xz);
888: #endif
889: if (ret == -ENOENT && nondirect)
890: ret = firmware_fallback_platform(fw->priv);
891:
892: if (ret) {
893: if (!(opt_flags & FW_OPT_NO_WARN))
894: dev_warn(device,
895: "Direct firmware load for %s failed with error %d\n",
896: name, ret);
897: if (nondirect)
898: ret = firmware_fallback_sysfs(fw, name, device,
899: opt_flags, ret);
900: } else {
901: ret = assign_fw(fw, device);
902: }
903: }
904:
905: out:
906: if (ret < 0) {
907: fw_abort_batch_reqs(fw);
908: release_firmware(fw);
909: fw = NULL;
910: } else {
911: fw_log_firmware_info(fw, name, device);
912: }
913:
914: *firmware_p = fw;
915: return ret;
916: }
SourceFile:drivers/base/firmware_loader/main.c]
|
| 28/2 |
2026/07/31 01:16 |
llm |
expert |
0m
Model:
Tokens:
input: 27023
output: 25
thoughts: 60
Thoughts: Okay, let's break this down.
**Diving into the `firmware_fallback_sysfs` Logic**
So, the code flow here is triggered when `nondirect` is true *and* the return value, `ret`, is non-zero. That's the condition that leads us to the `firmware_fallback_sysfs` function. My immediate thought is, "Okay, what's going on *inside* that function?" Because, as I recall, if `firmware_fallback_sysfs` is hit, it seems to involve creating some kind of sysfs device. That's a significant point to consider, so it needs closer examination. Let's delve into the guts of `firmware_fallback_sysfs` to understand its purpose and how it impacts the system state.
|
| 29/2 |
2026/07/31 01:16 |
tool |
codesearch-definition-source |
0m
Args: map[Name:firmware_fallback_sysfs]
Results: map[SourceCode: 202: /**
203: * firmware_fallback_sysfs() - use the fallback mechanism to find firmware
204: * @fw: pointer to firmware image
205: * @name: name of firmware file to look for
206: * @device: device for which firmware is being loaded
207: * @opt_flags: options to control firmware loading behaviour, as defined by
208: * &enum fw_opt
209: * @ret: return value from direct lookup which triggered the fallback mechanism
210: *
211: * This function is called if direct lookup for the firmware failed, it enables
212: * a fallback mechanism through userspace by exposing a sysfs loading
213: * interface. Userspace is in charge of loading the firmware through the sysfs
214: * loading interface. This sysfs fallback mechanism may be disabled completely
215: * on a system by setting the proc sysctl value ignore_sysfs_fallback to true.
216: * If this is false we check if the internal API caller set the
217: * @FW_OPT_NOFALLBACK_SYSFS flag, if so it would also disable the fallback
218: * mechanism. A system may want to enforce the sysfs fallback mechanism at all
219: * times, it can do this by setting ignore_sysfs_fallback to false and
220: * force_sysfs_fallback to true.
221: * Enabling force_sysfs_fallback is functionally equivalent to build a kernel
222: * with CONFIG_FW_LOADER_USER_HELPER_FALLBACK.
223: **/
224: int firmware_fallback_sysfs(struct firmware *fw, const char *name,
225: struct device *device,
226: u32 opt_flags,
227: int ret)
228: {
229: if (!fw_run_sysfs_fallback(opt_flags))
230: return ret;
231:
232: if (!(opt_flags & FW_OPT_NO_WARN))
233: dev_warn(device, "Falling back to sysfs fallback for: %s\n",
234: name);
235: else
236: dev_dbg(device, "Falling back to sysfs fallback for: %s\n",
237: name);
238: return fw_load_from_user_helper(fw, name, device, opt_flags);
239: }
SourceFile:drivers/base/firmware_loader/fallback.c]
|
| 30/2 |
2026/07/31 01:16 |
llm |
expert |
0m
Model:
Tokens:
input: 27995
output: 26
thoughts: 77
Thoughts: Okay, here's my interpretation of that thought process, tailored for an expert audience:
**Kernel Firmware Loading Fallback Logic**
Alright, I'm digging into how the firmware loading process handles the `sysfs` fallback mechanism. It seems like the core function, `fw_run_sysfs_fallback`, is the key to determining if we're even *using* the fallback. Now, this is crucial because in your typical production kernel – you know, the ones shipped to customers – the `CONFIG_FW_LOADER_USER_HELPER_FALLBACK` option is usually *disabled*. It's almost always disabled, and that's an important detail. But, the regular `CONFIG_FW_LOADER_USER_HELPER` *might* be enabled, which leads me to suspect that the fallback is still going to be used, in a slightly modified fashion. This tells me that `fw_run_sysfs_fallback` is where I need to focus my attention. It's the gatekeeper, the logical branch that determines if we're going to try to offload firmware loading to a user-space helper or if we're going to try something else. I need to understand how the function is used.
|
| 31/2 |
2026/07/31 01:16 |
tool |
codesearch-definition-source |
0m
Args: map[Name:fw_run_sysfs_fallback]
Results: map[SourceCode: 182: static bool fw_run_sysfs_fallback(u32 opt_flags)
183: {
184: int ret;
185:
186: if (fw_fallback_config.ignore_sysfs_fallback) {
187: pr_info_once("Ignoring firmware sysfs fallback due to sysctl knob\n");
188: return false;
189: }
190:
191: if ((opt_flags & FW_OPT_NOFALLBACK_SYSFS))
192: return false;
193:
194: /* Also permit LSMs and IMA to fail firmware sysfs fallback */
195: ret = security_kernel_load_data(LOADING_FIRMWARE, true);
196: if (ret < 0)
197: return false;
198:
199: return fw_force_sysfs_fallback(opt_flags);
200: }
SourceFile:drivers/base/firmware_loader/fallback.c]
|
| 32/2 |
2026/07/31 01:16 |
llm |
expert |
0m
Model:
Tokens:
input: 28664
output: 26
thoughts: 17
Thoughts: Okay, here's my interpretation of that thought process, tailored for an expert audience, and written in the first person:
**My Reasoning on `fw_force_sysfs_fallback`**
Alright, so the first thing I'm doing is checking a flag or state, likely a configuration setting or a command-line argument. I'm essentially trying to determine if a "fallback to sysfs" mode has been *forced* or explicitly requested. This suggests a few things, right off the bat. It implies:
* **We have an alternative:** The standard method of accessing firmware isn't necessarily `sysfs`. There's probably a more preferred or efficient way – maybe a kernel API, a device-specific driver interface, or a dedicated firmware loading subsystem.
* **There's a reason for the fallback:** The "forced" part implies that under *normal* circumstances, this fallback *wouldn't* be used. We're deliberately overriding the default behavior, and this likely points to either debugging/testing scenarios, compatibility issues with older systems, or a temporary workaround for a known problem.
* **Control is external:** The mechanism for setting this "forced" state is external to this function. It's either coming from a global setting, a kernel parameter, or a higher-level framework. I'm just here to react to that pre-existing directive.
So, essentially, this little piece of code is a conditional gatekeeper. It's asking, "Has someone *explicitly* told me to ignore the standard firmware access path and go straight to sysfs, *regardless* of the normal detection logic?" And my next steps will be determined by whether the answer is yes or no. The implications are significant as this affects everything downstream.
|
| 33/2 |
2026/07/31 01:16 |
tool |
codesearch-definition-source |
0m
Args: map[Name:fw_force_sysfs_fallback]
Results: map[SourceCode: 173: static bool fw_force_sysfs_fallback(u32 opt_flags)
174: {
175: if (fw_fallback_config.force_sysfs_fallback)
176: return true;
177: if (!(opt_flags & FW_OPT_USERHELPER))
178: return false;
179: return true;
180: }
SourceFile:drivers/base/firmware_loader/fallback.c]
|
| 34/2 |
2026/07/31 01:16 |
llm |
expert |
0m
Model:
Tokens:
input: 29228
output: 22
thoughts: 93
Thoughts: **Analyzing Firmware Request Logic**
Okay, so I'm looking at how firmware loading works, and it seems the execution path depends on a couple of conditions. It's supposed to only run if either `FW_OPT_USERHELPER` is set, or if `force_sysfs_fallback` is true. That makes sense, handling the different ways the firmware might be obtained.
Now, I see that `request_firmware` calls `_request_firmware`. The interesting part is the flags that are being passed to the latter, namely `FW_OPT_UEVENT | FW_OPT_FALLBACK`. Hmmm... that's the standard flags, it isn't relevant to how the system has been configured.
Wait a second… `FW_OPT_USERHELPER` *isn't* actually set by `request_firmware` itself. That feels wrong. I need to trace this back and understand how `FW_OPT_USERHELPER` gets set, and when. I need to check the call chain and understand the context better. I'm going to look at the implementation of `request_firmware` closely to figure out what's going on with this flag.
|
| 35/2 |
2026/07/31 01:17 |
tool |
codesearch-definition-source |
0m
Args: map[Name:request_firmware]
Results: map[SourceCode: 918: /**
919: * request_firmware() - send firmware request and wait for it
920: * @firmware_p: pointer to firmware image
921: * @name: name of firmware file
922: * @device: device for which firmware is being loaded
923: *
924: * @firmware_p will be used to return a firmware image by the name
925: * of @name for device @device.
926: *
927: * Should be called from user context where sleeping is allowed.
928: *
929: * @name will be used as $FIRMWARE in the uevent environment and
930: * should be distinctive enough not to be confused with any other
931: * firmware image for this or any other device.
932: * It must not contain any ".." path components - "foo/bar..bin" is
933: * allowed, but "foo/../bar.bin" is not.
934: *
935: * Caller must hold the reference count of @device.
936: *
937: * The function can be called safely inside device's suspend and
938: * resume callback.
939: **/
940: int
941: request_firmware(const struct firmware **firmware_p, const char *name,
942: struct device *device)
943: {
944: int ret;
945:
946: /* Need to pin this module until return */
947: __module_get(THIS_MODULE);
948: ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
949: FW_OPT_UEVENT);
950: module_put(THIS_MODULE);
951: return ret;
952: }
SourceFile:drivers/base/firmware_loader/main.c]
|
| 36/2 |
2026/07/31 01:17 |
llm |
expert |
0m
Model:
Tokens:
input: 30171
output: 23
thoughts: 85
Thoughts: **Analyzing Firmware Loading Behavior**
Okay, let's break this down. I'm looking at how this `request_firmware` function handles things, specifically concerning firmware loading and fallbacks. I see that `FW_OPT_UEVENT` is being passed into `request_firmware`, but crucially, `FW_OPT_USERHELPER` is *not*. This is a key observation.
Therefore, the `fw_force_sysfs_fallback` function is only going to return `true` if a specific condition is met. That condition, as I understand it, hinges on the `fw_fallback_config.force_sysfs_fallback` flag being set to `true`. Otherwise, it's going to default to `false`. So my next question is, what's the default state of this `fw_fallback_config.force_sysfs_fallback` variable? Is it initialized as `true`, or is it defaulted to `false`? Knowing this will dictate the standard behavior in this scenario, and whether we'll see that fallback occur as standard.
|
| 37/2 |
2026/07/31 01:17 |
tool |
codesearch-definition-source |
0m
Args: map[Name:fw_fallback_config]
Results: map[SourceCode: 20: struct firmware_fallback_config fw_fallback_config = {
21: .force_sysfs_fallback = IS_ENABLED(CONFIG_FW_LOADER_USER_HELPER_FALLBACK),
22: .loading_timeout = 60,
23: .old_timeout = 60,
24: };
SourceFile:drivers/base/firmware_loader/fallback_table.c]
|
| 38/2 |
2026/07/31 01:17 |
llm |
expert |
0m
Model:
Tokens:
input: 30633
output: 23
thoughts: 1100
Thoughts: **Analyzing the Firmware Loading Lock Dep Warning**
Okay, let's break this down. It all hinges on `CONFIG_FW_LOADER_USER_HELPER_FALLBACK`. In syzkaller kernels, it's often enabled for testing the fallback path, but in production, it's usually disabled. If it's disabled, the `firmware_fallback_sysfs` function just returns, bypassing the call to `fw_load_from_user_helper`. This means the user mode helper is *not* triggered, and critically, `try_to_freeze` is *not* called. The bug—the lockdep warning—is only reachable if the fallback is enabled or if `request_firmware_nowait` with `FW_OPT_USERHELPER` is used, though we're dealing with a regular `request_firmware` call here.
So, `request_firmware` is called from `devlink_compat_flash_update`, right? In production, this means it tries to load firmware directly from the filesystem. If it fails, it just returns an error. No 60-second sleeps, no user mode helper invocation, and definitely no `try_to_freeze`. Therefore, the lockdep warning is completely unreachable in production, and even if it *were* triggered, it's just a lockdep *warning*.
But, wait. `devlink_compat_flash_update` takes `devlink->lock_key`, and *then* calls `request_firmware`. `request_firmware` does file I/O, which can, and likely will, block. Is holding `devlink->lock_key` during blocking file I/O a problem? No, because it's a mutex; Mutexes can be held while sleeping. The only reason lockdep complains is that `try_to_freeze` gets called. `try_to_freeze` is called by `usermodehelper_read_trylock`, which in turn is called by `fw_load_from_user_helper`. So the lockdep warning is specifically about holding the `devlink->lock_key` lock while calling `try_to_freeze`. `try_to_freeze` could block until the system is thawed, and holding a lock during that period *could* cause a deadlock. However, `devlink->lock_key` isn't needed by other freezing threads, and in production, `try_to_freeze` *isn't* even called because `CONFIG_FW_LOADER_USER_HELPER_FALLBACK` is disabled. And even if it were, `debug_check_no_locks_held` is a no-op without `CONFIG_DEBUG_LOCK_ALLOC`.
So, the impact, as I see it, is as follows:
* **Exploitable:** No.
* **Denial of Service:** No, or at most, it could block a single `netdevsim` instance, which is *not* a system-wide DoS.
* **Accessible from unprivileged processes:** No, it requires `CAP_NET_ADMIN` in the network namespace.
* **Accessible from user namespaces:** Yes, it can create a netns and netdevsim device
* **VM Guest Trigger:** No.
* **VM Host Trigger:** No.
* **Network Trigger:** No.
* **Remote Trigger:** No.
* **Peripheral Trigger:** No.
* **Filesystem Trigger:** No.
Let me just double-check, though, on user privileges. Can `ETHTOOL_FLASHDEV` be called without any user namespaces?
In `dev_ethtool_locked`:
```c
switch (sub_cmd) {
case ETHTOOL_GSET:
...
case ETHTOOL_GFECPARAM:
break;
default:
if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
return -EPERM;
}
```
`ETHTOOL_FLASHDEV` isn't on the allowed list, so it requires `CAP_NET_ADMIN` in `net->user_ns`. If user namespaces are disabled, the user needs `CAP_NET_ADMIN` in the initial network namespace, which effectively means they're root. So, not accessible from unprivileged processes.
Just to be absolutely certain, is `devlink_compat_flash_update` the *only* path to this? Checking the stack trace:
```
devlink_compat_flash_update+0x134/0x27c net/devlink/dev.c:1247
dev_ethtool+
|
| 39/2 |
2026/07/31 01:17 |
tool |
codesearch-definition-source |
0m
Args:
Results: map[SourceCode:3646: int dev_ethtool(struct net *net, struct ifreq *ifr, void __user *useraddr)
3647: {
3648: struct ethtool_devlink_compat *state;
3649: u32 ethcmd;
3650: int rc;
3651:
3652: if (copy_from_user(ðcmd, useraddr, sizeof(ethcmd)))
3653: return -EFAULT;
3654:
3655: state = kzalloc_obj(*state);
3656: if (!state)
3657: return -ENOMEM;
3658:
3659: switch (ethcmd) {
3660: case ETHTOOL_FLASHDEV:
3661: if (copy_from_user(&state->efl, useraddr, sizeof(state->efl))) {
3662: rc = -EFAULT;
3663: goto exit_free;
3664: }
3665: state->efl.data[ETHTOOL_FLASH_MAX_FILENAME - 1] = 0;
3666: break;
3667: }
3668:
3669: rc = __dev_ethtool(net, ifr, useraddr, ethcmd, state);
3670: if (rc)
3671: goto exit_free;
3672:
3673: switch (ethcmd) {
3674: case ETHTOOL_FLASHDEV:
3675: if (state->devlink)
3676: rc = devlink_compat_flash_update(state->devlink,
3677: state->efl.data);
3678: break;
3679: case ETHTOOL_GDRVINFO:
3680: if (state->devlink)
3681: devlink_compat_running_version(state->devlink,
3682: state->info.fw_version,
3683: sizeof(state->info.fw_version));
3684: if (copy_to_user(useraddr, &state->info, sizeof(state->info))) {
3685: rc = -EFAULT;
3686: goto exit_free;
3687: }
3688: break;
3689: }
3690:
3691: exit_free:
3692: if (state->devlink)
3693: devlink_put(state->devlink);
3694: kfree(state);
3695: return rc;
3696: }
SourceFile:net/ethtool/ioctl.c]
|
| 40/2 |
2026/07/31 01:17 |
llm |
expert |
0m
Model:
Tokens:
input: 33533
output: 26
thoughts: 1107
Thoughts: **Analysis of the Firmware Update Vulnerability**
Okay, let's break this down. It seems we've got a lockdep warning related to `devlink_compat_flash_update`, and I think I see the sequence of events. The critical point is that `devlink_compat_flash_update` is called *after* `__dev_ethtool` finishes and, importantly, *after* `rtnl_lock` is released within `__dev_ethtool`. We know this because of the `netdev_unlock_ops(dev);` call and subsequent release of `rtnl_lock` in that code path.
So, when `devlink_compat_flash_update` runs, the only lock held is `devlink->lock_key`, which is acquired *inside* `devlink_compat_flash_update` via `devl_lock(devlink)`. This is a crucial observation. Because this function doesn't rely on any system-wide locks at this point, the entire operation is isolated to the specific `devlink` instance. This means even if the user mode helper is triggered and blocks for the full 60 seconds (which is a possibility with `request_firmware`), the impact is *extremely* limited.
Let's summarise the findings:
1. We are chasing a lockdep warning.
2. The warning appears because `request_firmware` is called with `devlink->lock_key` already held.
3. The `request_firmware` function can potentially trigger the user mode helper fallback. This is likely when `CONFIG_FW_LOADER_USER_HELPER_FALLBACK` is enabled, which is often the case in fuzzing environments like syzkaller. This is a significant detail.
4. The fallback scenario might lead to `try_to_freeze`, which then uses `debug_check_no_locks_held()`.
5. Critically, `debug_check_no_locks_held()` is a no-op in a standard production kernel. Debugging checks are great, but have no effect on product!
6. Even if we do end up blocked by the fallback, it's just the `devlink->lock_key` on *that* specific device instance for 60 seconds. It doesn't impact anything system-wide.
7. The user needs `CAP_NET_ADMIN` within a network namespace to even trigger the bug (verified via `dev_ethtool_locked`).
8. An unprivileged user can create a user namespace, a network namespace, and then a `netdevsim` device to test this.
9. This entire issue is contained. It is only affecting the user's `netdevsim` instance. It cannot crash the kernel. There is no security impact!
Therefore, I think this isn't a security vulnerability because it's not a denial of service. The user can effectively block *themselves* from interacting with *their* `netdevsim` device, but nothing more.
Now, let me double-check for other angles.
Could there be something wrong with the firmware loading itself? The user specifies the `file_name` via `ETHTOOL_FLASHDEV`. We know this is copied from userspace. So, a user can provide their own filename. This is important to study. It calls `request_firmware`.
The code copies the filename using `copy_from_user` and then calls `request_firmware(¶ms.fw, file_name, devlink->dev);`. `request_firmware` will look for the firmware in standard places. The user is allowed to specify any filename. Let's see if the code protects from path traversal attacks via `..`. The code that calls `_request_firmware` uses a check:
```c
if (name_contains_dotdot(name)) {
dev_warn(device,
"Firmware load for '%s' refused, path contains '..' component\n",
name);
ret = -EINVAL;
goto out;
}
```
The code checks for `..`! The user cannot escape the firmware directory. This is good. It prevents local privilege escalation. The filename is sanitized.
Even if the user mode helper is triggered, it is passed the filename. The user mode helper runs as root, so it is privileged. Could there be an issue if the user mode helper is called? In production, `CONFIG_FW_LOADER_USER_HELPER_FALLBACK` is usually disabled anyway. If it is enabled, the filename is sanitized (no `..`). Again, this is a well-known, controlled behavior.
|
| 41/2 |
2026/07/31 01:17 |
tool |
codesearch-definition-source |
0m
Args: map[Name:nsim_dev_flash_update]
Results: map[SourceCode:1079: static int nsim_dev_flash_update(struct devlink *devlink,
1080: struct devlink_flash_update_params *params,
1081: struct netlink_ext_ack *extack)
1082: {
1083: struct nsim_dev *nsim_dev = devlink_priv(devlink);
1084: int i;
1085:
1086: if ((params->overwrite_mask & ~nsim_dev->fw_update_overwrite_mask) != 0)
1087: return -EOPNOTSUPP;
1088:
1089: if (nsim_dev->fw_update_status) {
1090: devlink_flash_update_status_notify(devlink,
1091: "Preparing to flash",
1092: params->component, 0, 0);
1093: }
1094:
1095: for (i = 0; i < NSIM_DEV_FLASH_SIZE / NSIM_DEV_FLASH_CHUNK_SIZE; i++) {
1096: if (nsim_dev->fw_update_status)
1097: devlink_flash_update_status_notify(devlink, "Flashing",
1098: params->component,
1099: i * NSIM_DEV_FLASH_CHUNK_SIZE,
1100: NSIM_DEV_FLASH_SIZE);
1101: msleep(nsim_dev->fw_update_flash_chunk_time_ms ?: 1);
1102: }
1103:
1104: if (nsim_dev->fw_update_status) {
1105: devlink_flash_update_status_notify(devlink, "Flashing",
1106: params->component,
1107: NSIM_DEV_FLASH_SIZE,
1108: NSIM_DEV_FLASH_SIZE);
1109: devlink_flash_update_timeout_notify(devlink, "Flash select",
1110: params->component, 81);
1111: devlink_flash_update_status_notify(devlink, "Flashing done",
1112: params->component, 0, 0);
1113: }
1114:
1115: return 0;
1116: }
SourceFile:drivers/net/netdevsim/dev.c]
|
| 42/2 |
2026/07/31 01:17 |
llm |
expert |
0m
Model:
Tokens:
input: 36370
output: 26
thoughts: 516
Thoughts: **Bug Analysis: `nsim_dev_flash_update` Lockdep Warning**
Okay, so I've looked at this. `nsim_dev_flash_update` is just a placeholder, a simulated "flash" operation. It's not doing anything that should cause any real problems. The core of the issue is a lockdep warning. It's about holding a lock when calling `try_to_freeze`. Classic issue, really – this kind of thing pops up when you're working with `request_firmware` and locks.
It's a textbook example of a *minor* bug, but not a security vulnerability. No memory corruption, no information leaks, and certainly no system-wide DoS risk. So, the initial assessment:
* **Exploitable: False**
* **DenialOfService: False**
* **Unprivileged: False** (needs `CAP_NET_ADMIN` within a network namespace, which isn't available by default.)
* **UserNamespace: True** (that seems to be a significant detail)
* **VMGuestTrigger: False**
* **VMHostTrigger: False**
* **NetworkTrigger: False**
* **RemoteTrigger: False**
* **PeripheralTrigger: False**
* **FilesystemTrigger: False**
Hold on... I need to be completely clear. Can an *unprivileged* user actually trigger this? That's the key question. It requires `CAP_NET_ADMIN` in a network namespace. But, wait... you can create a user namespace and then a network namespace. So, then you have `CAP_NET_ADMIN` in that *new* network namespace. Bingo! They could instantiate `netdevsim` and trigger the warning. So **UserNamespace** is confirmed True.
Okay, let's just make sure about that `netdevsim` device creation. How exactly is `netdevsim` created? It uses that `netdevsim` bus, a virtual bus. To create the device, you write to `/sys/bus/netdevsim/new_device`. Sysfs is usually read-only within user namespaces, right? Unless it's a network namespace that owns the initial sysfs mount...
No, wait. Sysfs isn't really network namespace-aware in that way. But the thing is, `/sys/bus/netdevsim/new_device` is owned by root in the initial user namespace. Can an unprivileged user in *their* user namespace actually write to it? No. They don't have write access. Okay, so that's the final piece of the puzzle. So the analysis still stands. This is the whole picture.
|
| 43/2 |
2026/07/31 01:17 |
tool |
codesearch-definition-source |
0m
Args: map[Name:nsim_bus_dev_new]
Results: map[SourceCode: 448: static struct nsim_bus_dev *
449: nsim_bus_dev_new(unsigned int id, unsigned int port_count, unsigned int num_queues)
450: {
451: struct nsim_bus_dev *nsim_bus_dev;
452: int err;
453:
454: nsim_bus_dev = kzalloc_obj(*nsim_bus_dev);
455: if (!nsim_bus_dev)
456: return ERR_PTR(-ENOMEM);
457:
458: err = ida_alloc_range(&nsim_bus_dev_ids, id, id, GFP_KERNEL);
459: if (err < 0)
460: goto err_nsim_bus_dev_free;
461: nsim_bus_dev->dev.id = err;
462: nsim_bus_dev->dev.bus = &nsim_bus;
463: nsim_bus_dev->dev.type = &nsim_bus_dev_type;
464: nsim_bus_dev->port_count = port_count;
465: nsim_bus_dev->num_queues = num_queues;
466: nsim_bus_dev->initial_net = current->nsproxy->net_ns;
467: nsim_bus_dev->max_vfs = NSIM_BUS_DEV_MAX_VFS;
468: /* Disallow using nsim_bus_dev */
469: smp_store_release(&nsim_bus_dev->init, false);
470:
471: err = device_register(&nsim_bus_dev->dev);
472: if (err)
473: goto err_nsim_bus_dev_id_free;
474:
475: return nsim_bus_dev;
476:
477: err_nsim_bus_dev_id_free:
478: ida_free(&nsim_bus_dev_ids, nsim_bus_dev->dev.id);
479: put_device(&nsim_bus_dev->dev);
480: nsim_bus_dev = NULL;
481: err_nsim_bus_dev_free:
482: kfree(nsim_bus_dev);
483: return ERR_PTR(err);
484: }
SourceFile:drivers/net/netdevsim/bus.c]
|
| 44/2 |
2026/07/31 01:17 |
llm |
expert |
0m
Model:
Tokens:
input: 38208
output: 26
thoughts: 13
Thoughts: Okay, here's my take on those thoughts, framed as an expert's internal reflection:
**Tracing the Origins of `nsim_bus_dev_new`**
Right, so the question immediately that pops into my head is, "Who's the caller?" That's the critical first step. I need to understand the context of `nsim_bus_dev_new`. Is it part of the core driver, a plugin, a test suite, or something else entirely? Knowing the calling function and even, ideally, the calling module, gives me a huge leg up. I can't start analyzing the function in isolation; I have to understand its *purpose* within the bigger picture.
My usual approach at this point is to start searching the codebase. A quick `grep` or `find` command will probably uncover the relevant usages. I'm looking for the immediate callers, but I'll be mindful of indirect calls as well. Are there wrapper functions? Are there macros involved? Understanding the call stack is going to be essential. I also will want to consider cross-references in the documentation, even if the docstrings are poorly written or incomplete.
What about conditional compilation? It could be called from only some parts of the system or at specific build configurations. I need to be prepared to see `#ifdef` or `#if` statements that control when this function gets invoked. This impacts the scenarios I need to consider for understanding the code's behavior. Are there any hardware dependencies that might control whether this gets called?
Once I have a list of callers, I'll then move towards understanding *why* they're calling `nsim_bus_dev_new`. What data is being passed in? What is being returned? The parameters and the return value provide valuable clues about the function's responsibility and the object's life cycle. So, from there, I'll build a mental model of the object it constructs and why the caller needs it. I'm going to follow the data, tracing where this newly created `nsim_bus_dev` is used, modified, and eventually freed. That's the real key to understanding its place in the grand scheme of things.
|
| 45/2 |
2026/07/31 01:17 |
tool |
codesearch-find-references |
0m
Args: map[Name:nsim_bus_dev_new]
Results: map[References:[map[ReferenceKind:calls ReferencingEntityKind:function ReferencingEntityName:new_device_store SourceFile:drivers/net/netdevsim/bus.c SourceLine:191]] TruncatedOutput:false]
|
| 46/2 |
2026/07/31 01:17 |
llm |
expert |
0m
Model:
Tokens:
input: 38779
output: 23
thoughts: 13
Thoughts: Okay, here's my interpretation of that thought, summarized in the first person, assuming an expert audience:
**Analyzing the `new_device_store` sysfs Attribute**
Alright, so the key piece of this puzzle is the `new_device_store` attribute within the sysfs filesystem. My understanding is that this attribute, specifically, is the entry point for handling new device enumeration or maybe even device instantiation in the system. The specific behavior would depend on context, of course – it could be related to hotplug events, driver initialization routines, or even user-space triggered device creation. I immediately think about what kind of data is written to it. Is it a device ID, a path, some sort of configuration data? Understanding the data format is critical to understanding what actions this attribute triggers, and how to effectively leverage it. I'll need to dig deeper into the kernel code that touches this sysfs attribute. What driver is responsible? What are the implications if I manipulate it directly versus using established APIs? The possibilities, and potential pitfalls, are already starting to reveal themselves. Time to investigate further.
|
| 47/2 |
2026/07/31 01:17 |
tool |
codesearch-definition-source |
0m
Args: map[Name:new_device_store]
Results: map[SourceCode: 158: static ssize_t
159: new_device_store(const struct bus_type *bus, const char *buf, size_t count)
160: {
161: unsigned int id, port_count, num_queues;
162: struct nsim_bus_dev *nsim_bus_dev;
163: int err;
164:
165: err = sscanf(buf, "%u %u %u", &id, &port_count, &num_queues);
166: switch (err) {
167: case 1:
168: port_count = 1;
169: fallthrough;
170: case 2:
171: num_queues = 1;
172: fallthrough;
173: case 3:
174: if (id > INT_MAX) {
175: pr_err("Value of \"id\" is too big.\n");
176: return -EINVAL;
177: }
178: break;
179: default:
180: pr_err("Format for adding new device is \"id port_count num_queues\" (uint uint uint).\n");
181: return -EINVAL;
182: }
183:
184: mutex_lock(&nsim_bus_dev_list_lock);
185: /* Prevent to use resource before initialization. */
186: if (!smp_load_acquire(&nsim_bus_enable)) {
187: err = -EBUSY;
188: goto err;
189: }
190:
191: nsim_bus_dev = nsim_bus_dev_new(id, port_count, num_queues);
192: if (IS_ERR(nsim_bus_dev)) {
193: err = PTR_ERR(nsim_bus_dev);
194: goto err;
195: }
196:
197: refcount_inc(&nsim_bus_devs);
198: /* Allow using nsim_bus_dev */
199: smp_store_release(&nsim_bus_dev->init, true);
200:
201: list_add_tail(&nsim_bus_dev->list, &nsim_bus_dev_list);
202: mutex_unlock(&nsim_bus_dev_list_lock);
203:
204: return count;
205: err:
206: mutex_unlock(&nsim_bus_dev_list_lock);
207: return err;
208: }
SourceFile:drivers/net/netdevsim/bus.c]
|
| 48/2 |
2026/07/31 01:17 |
llm |
expert |
0m
Model:
Tokens:
input: 39843
output: 26
thoughts: 209
Thoughts: **Analyzing `new_device_store` Access**
Okay, so this `new_device_store` thing... it's a sysfs attribute. Instinctively, I know those are usually owned by root. The real question is, can a user *within* a user namespace write to it? The answer is almost certainly no. Sysfs is typically mounted read-only in user namespaces, and even if it weren't, the file itself is owned by `root:root` in the initial namespace, which is going to create permission problems.
But then I think about syzkaller. How the heck *is* syzkaller triggering this if it's generally inaccessible? It must be running with root privileges either in the initial user namespace, or it must be running in a test environment where it has access to `/sys/bus/netdevsim/new_device`. If this *does* require root in the initial namespace to create the device, then it's effectively inaccessible from a user namespace. At least, unless the device is created and then moved into the user namespace, which would be a separate problem.
Hang on... I'm remembering something about `netdevsim` and netlink. Wait, isn't there a netlink interface for creating these devices? That's the key here. I've got to check and see if there's a netlink interface available to create `netdevsim` devices. That's the most likely avenue.
|
| 49/2 |
2026/07/31 01:18 |
tool |
codesearch-find-references |
0m
Args: map[Name:nsim_bus_dev_new]
Results: map[References:[map[ReferenceKind:calls ReferencingEntityKind:function ReferencingEntityName:new_device_store SourceFile:drivers/net/netdevsim/bus.c SourceLine:191]] TruncatedOutput:false]
|
| 50/2 |
2026/07/31 01:18 |
llm |
expert |
0m
Model:
Tokens:
input: 40460
output: 29
thoughts: 420
Thoughts: **Analyzing Potential Security Implications of Network Device Management**
Okay, so I'm focusing on network device creation and manipulation, specifically around firmware flashing. I'm thinking, my system only supports new device stores. So, `netdevsim` devices, which I know I'm already using, can only be created by root in the initial user namespace. Makes sense. But what about real devices, like `mlx5` or `ice`? They're also created by root or through a hardware hotplug.
Here's where it gets interesting. If root *moves* a real device to a network namespace owned by an unprivileged user, that user then gains `CAP_NET_ADMIN` within *that* specific namespace. I'm wondering, can this unprivileged user then call something like `ETHTOOL_FLASHDEV` on it?
Aha! `dev_ethtool_locked` checks `ns_capable(net->user_ns, CAP_NET_ADMIN)`. So, yes, if root moves the interface, the user *can* call `ETHTOOL_FLASHDEV`. Is this a potential security hole?
Well, if the unprivileged user can flash firmware on a real device, that *could* potentially allow them to compromise the device firmware. I'm realizing `ETHTOOL_FLASHDEV` *explicitly* allows for firmware flashing. So, if root moves a device, does the user essentially get firmware flashing permissions?
Time to look deeper. Let's check `devlink_compat_flash_update`. I see it calls `request_firmware`. And that, crucially, uses the kernel credentials to *read* the firmware file, but crucially from `/lib/firmware`. Okay, this is key. So, the user can only flash firmware that's *already* present in `/lib/firmware`.
But, wait... If the user can *specify* the filename, they can flash *any* firmware present in `/lib/firmware`! Now, *that* could be a problem. If there are multiple firmware versions in `/lib/firmware`, the user could downgrade the firmware to a known vulnerable version. Or even worse, flash the firmware for a *different* device (though the driver might reject this, it's not guaranteed).
Ah, but wait... `devlink_compat_flash_update` is the *compatibility* path, isn't it? The more modern way is via `devlink_nl_flash_update_doit`. I need to look into *that* code path.
|
| 51/2 |
2026/07/31 01:18 |
tool |
codesearch-definition-source |
0m
Args: map[Name:devlink_nl_flash_update_doit]
Results: map[SourceCode:1133: int devlink_nl_flash_update_doit(struct sk_buff *skb, struct genl_info *info)
1134: {
1135: struct nlattr *nla_overwrite_mask, *nla_file_name;
1136: struct devlink_flash_update_params params = {};
1137: struct devlink *devlink = info->user_ptr[0];
1138: const char *file_name;
1139: u32 supported_params;
1140: int ret;
1141:
1142: if (!devlink->ops->flash_update)
1143: return -EOPNOTSUPP;
1144:
1145: if (GENL_REQ_ATTR_CHECK(info, DEVLINK_ATTR_FLASH_UPDATE_FILE_NAME))
1146: return -EINVAL;
1147:
1148: ret = devlink_flash_component_get(devlink,
1149: info->attrs[DEVLINK_ATTR_FLASH_UPDATE_COMPONENT],
1150: ¶ms.component, info->extack);
1151: if (ret)
1152: return ret;
1153:
1154: supported_params = devlink->ops->supported_flash_update_params;
1155:
1156: nla_overwrite_mask = info->attrs[DEVLINK_ATTR_FLASH_UPDATE_OVERWRITE_MASK];
1157: if (nla_overwrite_mask) {
1158: struct nla_bitfield32 sections;
1159:
1160: if (!(supported_params & DEVLINK_SUPPORT_FLASH_UPDATE_OVERWRITE_MASK)) {
1161: NL_SET_ERR_MSG_ATTR(info->extack, nla_overwrite_mask,
1162: "overwrite settings are not supported by this device");
1163: return -EOPNOTSUPP;
1164: }
1165: sections = nla_get_bitfield32(nla_overwrite_mask);
1166: params.overwrite_mask = sections.value & sections.selector;
1167: }
1168:
1169: nla_file_name = info->attrs[DEVLINK_ATTR_FLASH_UPDATE_FILE_NAME];
1170: file_name = nla_data(nla_file_name);
1171: ret = request_firmware(¶ms.fw, file_name, devlink->dev);
1172: if (ret) {
1173: NL_SET_ERR_MSG_ATTR(info->extack, nla_file_name,
1174: "failed to locate the requested firmware file");
1175: return ret;
1176: }
1177:
1178: devlink_flash_update_begin_notify(devlink);
1179: ret = devlink->ops->flash_update(devlink, ¶ms, info->extack);
1180: devlink_flash_update_end_notify(devlink);
1181:
1182: release_firmware(params.fw);
1183:
1184: return ret;
1185: }
SourceFile:net/devlink/dev.c]
|
| 52/2 |
2026/07/31 01:18 |
llm |
expert |
0m
Model:
Tokens:
input: 42368
output: 24
thoughts: 48
Thoughts: Okay, here's my take on those thoughts, framed as an expert's internal monologue:
**Checking Devlink Netlink Permissions**
Right, so we're dealing with `devlink_nl_flash_update_doit`. That's a devlink netlink command, and if memory serves, all those devlink netlink commands require the `GENL_ADMIN_PERM` permission. So, the first step, as always, is to double-check that permission and make sure our context has it before we attempt anything further. No point wasting time or, worse, running into security issues later. Let's dig into the devlink netlink permission structure.
|
| 53/2 |
2026/07/31 01:18 |
tool |
codesearch-definition-source |
0m
Args:
Results: map[SourceCode: 693: /* Ops table for devlink */
694: const struct genl_split_ops devlink_nl_ops[75] = {
695: {
696: .cmd = DEVLINK_CMD_GET,
697: .validate = GENL_DONT_VALIDATE_STRICT,
698: .pre_doit = devlink_nl_pre_doit,
699: .doit = devlink_nl_get_doit,
700: .post_doit = devlink_nl_post_doit,
701: .policy = devlink_get_nl_policy,
702: .maxattr = DEVLINK_ATTR_INDEX,
703: .flags = GENL_CMD_CAP_DO,
704: },
705: {
706: .cmd = DEVLINK_CMD_GET,
707: .validate = GENL_DONT_VALIDATE_DUMP,
708: .dumpit = devlink_nl_get_dumpit,
709: .flags = GENL_CMD_CAP_DUMP,
710: },
711: {
712: .cmd = DEVLINK_CMD_PORT_GET,
713: .validate = GENL_DONT_VALIDATE_STRICT,
714: .pre_doit = devlink_nl_pre_doit_port,
715: .doit = devlink_nl_port_get_doit,
716: .post_doit = devlink_nl_post_doit,
717: .policy = devlink_port_get_do_nl_policy,
718: .maxattr = DEVLINK_ATTR_INDEX,
719: .flags = GENL_CMD_CAP_DO,
720: },
721: {
722: .cmd = DEVLINK_CMD_PORT_GET,
723: .dumpit = devlink_nl_port_get_dumpit,
724: .policy = devlink_port_get_dump_nl_policy,
725: .maxattr = DEVLINK_ATTR_INDEX,
726: .flags = GENL_CMD_CAP_DUMP,
727: },
728: {
729: .cmd = DEVLINK_CMD_PORT_SET,
730: .validate = GENL_DONT_VALIDATE_STRICT,
731: .pre_doit = devlink_nl_pre_doit_port,
732: .doit = devlink_nl_port_set_doit,
733: .post_doit = devlink_nl_post_doit,
734: .policy = devlink_port_set_nl_policy,
735: .maxattr = DEVLINK_ATTR_INDEX,
736: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
737: },
738: {
739: .cmd = DEVLINK_CMD_PORT_NEW,
740: .validate = GENL_DONT_VALIDATE_STRICT,
741: .pre_doit = devlink_nl_pre_doit,
742: .doit = devlink_nl_port_new_doit,
743: .post_doit = devlink_nl_post_doit,
744: .policy = devlink_port_new_nl_policy,
745: .maxattr = DEVLINK_ATTR_INDEX,
746: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
747: },
748: {
749: .cmd = DEVLINK_CMD_PORT_DEL,
750: .validate = GENL_DONT_VALIDATE_STRICT,
751: .pre_doit = devlink_nl_pre_doit_port,
752: .doit = devlink_nl_port_del_doit,
753: .post_doit = devlink_nl_post_doit,
754: .policy = devlink_port_del_nl_policy,
755: .maxattr = DEVLINK_ATTR_INDEX,
756: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
757: },
758: {
759: .cmd = DEVLINK_CMD_PORT_SPLIT,
760: .validate = GENL_DONT_VALIDATE_STRICT,
761: .pre_doit = devlink_nl_pre_doit_port,
762: .doit = devlink_nl_port_split_doit,
763: .post_doit = devlink_nl_post_doit,
764: .policy = devlink_port_split_nl_policy,
765: .maxattr = DEVLINK_ATTR_INDEX,
766: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
767: },
768: {
769: .cmd = DEVLINK_CMD_PORT_UNSPLIT,
770: .validate = GENL_DONT_VALIDATE_STRICT,
771: .pre_doit = devlink_nl_pre_doit_port,
772: .doit = devlink_nl_port_unsplit_doit,
773: .post_doit = devlink_nl_post_doit,
774: .policy = devlink_port_unsplit_nl_policy,
775: .maxattr = DEVLINK_ATTR_INDEX,
776: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
777: },
778: {
779: .cmd = DEVLINK_CMD_SB_GET,
780: .validate = GENL_DONT_VALIDATE_STRICT,
781: .pre_doit = devlink_nl_pre_doit,
782: .doit = devlink_nl_sb_get_doit,
783: .post_doit = devlink_nl_post_doit,
784: .policy = devlink_sb_get_do_nl_policy,
785: .maxattr = DEVLINK_ATTR_INDEX,
786: .flags = GENL_CMD_CAP_DO,
787: },
788: {
789: .cmd = DEVLINK_CMD_SB_GET,
790: .dumpit = devlink_nl_sb_get_dumpit,
791: .policy = devlink_sb_get_dump_nl_policy,
792: .maxattr = DEVLINK_ATTR_INDEX,
793: .flags = GENL_CMD_CAP_DUMP,
794: },
795: {
796: .cmd = DEVLINK_CMD_SB_POOL_GET,
797: .validate = GENL_DONT_VALIDATE_STRICT,
798: .pre_doit = devlink_nl_pre_doit,
799: .doit = devlink_nl_sb_pool_get_doit,
800: .post_doit = devlink_nl_post_doit,
801: .policy = devlink_sb_pool_get_do_nl_policy,
802: .maxattr = DEVLINK_ATTR_INDEX,
803: .flags = GENL_CMD_CAP_DO,
804: },
805: {
806: .cmd = DEVLINK_CMD_SB_POOL_GET,
807: .dumpit = devlink_nl_sb_pool_get_dumpit,
808: .policy = devlink_sb_pool_get_dump_nl_policy,
809: .maxattr = DEVLINK_ATTR_INDEX,
810: .flags = GENL_CMD_CAP_DUMP,
811: },
812: {
813: .cmd = DEVLINK_CMD_SB_POOL_SET,
814: .validate = GENL_DONT_VALIDATE_STRICT,
815: .pre_doit = devlink_nl_pre_doit,
816: .doit = devlink_nl_sb_pool_set_doit,
817: .post_doit = devlink_nl_post_doit,
818: .policy = devlink_sb_pool_set_nl_policy,
819: .maxattr = DEVLINK_ATTR_INDEX,
820: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
821: },
822: {
823: .cmd = DEVLINK_CMD_SB_PORT_POOL_GET,
824: .validate = GENL_DONT_VALIDATE_STRICT,
825: .pre_doit = devlink_nl_pre_doit_port,
826: .doit = devlink_nl_sb_port_pool_get_doit,
827: .post_doit = devlink_nl_post_doit,
828: .policy = devlink_sb_port_pool_get_do_nl_policy,
829: .maxattr = DEVLINK_ATTR_INDEX,
830: .flags = GENL_CMD_CAP_DO,
831: },
832: {
833: .cmd = DEVLINK_CMD_SB_PORT_POOL_GET,
834: .dumpit = devlink_nl_sb_port_pool_get_dumpit,
835: .policy = devlink_sb_port_pool_get_dump_nl_policy,
836: .maxattr = DEVLINK_ATTR_INDEX,
837: .flags = GENL_CMD_CAP_DUMP,
838: },
839: {
840: .cmd = DEVLINK_CMD_SB_PORT_POOL_SET,
841: .validate = GENL_DONT_VALIDATE_STRICT,
842: .pre_doit = devlink_nl_pre_doit_port,
843: .doit = devlink_nl_sb_port_pool_set_doit,
844: .post_doit = devlink_nl_post_doit,
845: .policy = devlink_sb_port_pool_set_nl_policy,
846: .maxattr = DEVLINK_ATTR_INDEX,
847: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
848: },
849: {
850: .cmd = DEVLINK_CMD_SB_TC_POOL_BIND_GET,
851: .validate = GENL_DONT_VALIDATE_STRICT,
852: .pre_doit = devlink_nl_pre_doit_port,
853: .doit = devlink_nl_sb_tc_pool_bind_get_doit,
854: .post_doit = devlink_nl_post_doit,
855: .policy = devlink_sb_tc_pool_bind_get_do_nl_policy,
856: .maxattr = DEVLINK_ATTR_INDEX,
857: .flags = GENL_CMD_CAP_DO,
858: },
859: {
860: .cmd = DEVLINK_CMD_SB_TC_POOL_BIND_GET,
861: .dumpit = devlink_nl_sb_tc_pool_bind_get_dumpit,
862: .policy = devlink_sb_tc_pool_bind_get_dump_nl_policy,
863: .maxattr = DEVLINK_ATTR_INDEX,
864: .flags = GENL_CMD_CAP_DUMP,
865: },
866: {
867: .cmd = DEVLINK_CMD_SB_TC_POOL_BIND_SET,
868: .validate = GENL_DONT_VALIDATE_STRICT,
869: .pre_doit = devlink_nl_pre_doit_port,
870: .doit = devlink_nl_sb_tc_pool_bind_set_doit,
871: .post_doit = devlink_nl_post_doit,
872: .policy = devlink_sb_tc_pool_bind_set_nl_policy,
873: .maxattr = DEVLINK_ATTR_INDEX,
874: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
875: },
876: {
877: .cmd = DEVLINK_CMD_SB_OCC_SNAPSHOT,
878: .validate = GENL_DONT_VALIDATE_STRICT,
879: .pre_doit = devlink_nl_pre_doit,
880: .doit = devlink_nl_sb_occ_snapshot_doit,
881: .post_doit = devlink_nl_post_doit,
882: .policy = devlink_sb_occ_snapshot_nl_policy,
883: .maxattr = DEVLINK_ATTR_INDEX,
884: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
885: },
886: {
887: .cmd = DEVLINK_CMD_SB_OCC_MAX_CLEAR,
888: .validate = GENL_DONT_VALIDATE_STRICT,
889: .pre_doit = devlink_nl_pre_doit,
890: .doit = devlink_nl_sb_occ_max_clear_doit,
891: .post_doit = devlink_nl_post_doit,
892: .policy = devlink_sb_occ_max_clear_nl_policy,
893: .maxattr = DEVLINK_ATTR_INDEX,
894: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
895: },
896: {
897: .cmd = DEVLINK_CMD_ESWITCH_GET,
898: .validate = GENL_DONT_VALIDATE_STRICT,
899: .pre_doit = devlink_nl_pre_doit,
900: .doit = devlink_nl_eswitch_get_doit,
901: .post_doit = devlink_nl_post_doit,
902: .policy = devlink_eswitch_get_nl_policy,
903: .maxattr = DEVLINK_ATTR_INDEX,
904: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
905: },
906: {
907: .cmd = DEVLINK_CMD_ESWITCH_SET,
908: .validate = GENL_DONT_VALIDATE_STRICT,
909: .pre_doit = devlink_nl_pre_doit,
910: .doit = devlink_nl_eswitch_set_doit,
911: .post_doit = devlink_nl_post_doit,
912: .policy = devlink_eswitch_set_nl_policy,
913: .maxattr = DEVLINK_ATTR_INDEX,
914: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
915: },
916: {
917: .cmd = DEVLINK_CMD_DPIPE_TABLE_GET,
918: .validate = GENL_DONT_VALIDATE_STRICT,
919: .pre_doit = devlink_nl_pre_doit,
920: .doit = devlink_nl_dpipe_table_get_doit,
921: .post_doit = devlink_nl_post_doit,
922: .policy = devlink_dpipe_table_get_nl_policy,
923: .maxattr = DEVLINK_ATTR_INDEX,
924: .flags = GENL_CMD_CAP_DO,
925: },
926: {
927: .cmd = DEVLINK_CMD_DPIPE_ENTRIES_GET,
928: .validate = GENL_DONT_VALIDATE_STRICT,
929: .pre_doit = devlink_nl_pre_doit,
930: .doit = devlink_nl_dpipe_entries_get_doit,
931: .post_doit = devlink_nl_post_doit,
932: .policy = devlink_dpipe_entries_get_nl_policy,
933: .maxattr = DEVLINK_ATTR_INDEX,
934: .flags = GENL_CMD_CAP_DO,
935: },
936: {
937: .cmd = DEVLINK_CMD_DPIPE_HEADERS_GET,
938: .validate = GENL_DONT_VALIDATE_STRICT,
939: .pre_doit = devlink_nl_pre_doit,
940: .doit = devlink_nl_dpipe_headers_get_doit,
941: .post_doit = devlink_nl_post_doit,
942: .policy = devlink_dpipe_headers_get_nl_policy,
943: .maxattr = DEVLINK_ATTR_INDEX,
944: .flags = GENL_CMD_CAP_DO,
945: },
946: {
947: .cmd = DEVLINK_CMD_DPIPE_TABLE_COUNTERS_SET,
948: .validate = GENL_DONT_VALIDATE_STRICT,
949: .pre_doit = devlink_nl_pre_doit,
950: .doit = devlink_nl_dpipe_table_counters_set_doit,
951: .post_doit = devlink_nl_post_doit,
952: .policy = devlink_dpipe_table_counters_set_nl_policy,
953: .maxattr = DEVLINK_ATTR_INDEX,
954: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
955: },
956: {
957: .cmd = DEVLINK_CMD_RESOURCE_SET,
958: .validate = GENL_DONT_VALIDATE_STRICT,
959: .pre_doit = devlink_nl_pre_doit,
960: .doit = devlink_nl_resource_set_doit,
961: .post_doit = devlink_nl_post_doit,
962: .policy = devlink_resource_set_nl_policy,
963: .maxattr = DEVLINK_ATTR_INDEX,
964: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
965: },
966: {
967: .cmd = DEVLINK_CMD_RESOURCE_DUMP,
968: .validate = GENL_DONT_VALIDATE_STRICT,
969: .pre_doit = devlink_nl_pre_doit_port_optional,
970: .doit = devlink_nl_resource_dump_doit,
971: .post_doit = devlink_nl_post_doit,
972: .policy = devlink_resource_dump_do_nl_policy,
973: .maxattr = DEVLINK_ATTR_INDEX,
974: .flags = GENL_CMD_CAP_DO,
975: },
976: {
977: .cmd = DEVLINK_CMD_RESOURCE_DUMP,
978: .dumpit = devlink_nl_resource_dump_dumpit,
979: .policy = devlink_resource_dump_dump_nl_policy,
980: .maxattr = DEVLINK_ATTR_RESOURCE_SCOPE_MASK,
981: .flags = GENL_CMD_CAP_DUMP,
982: },
983: {
984: .cmd = DEVLINK_CMD_RELOAD,
985: .validate = GENL_DONT_VALIDATE_STRICT,
986: .pre_doit = devlink_nl_pre_doit_dev_lock,
987: .doit = devlink_nl_reload_doit,
988: .post_doit = devlink_nl_post_doit_dev_lock,
989: .policy = devlink_reload_nl_policy,
990: .maxattr = DEVLINK_ATTR_INDEX,
991: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
992: },
993: {
994: .cmd = DEVLINK_CMD_PARAM_GET,
995: .validate = GENL_DONT_VALIDATE_STRICT,
996: .pre_doit = devlink_nl_pre_doit,
997: .doit = devlink_nl_param_get_doit,
998: .post_doit = devlink_nl_post_doit,
999: .policy = devlink_param_get_do_nl_policy,
1000: .maxattr = DEVLINK_ATTR_INDEX,
1001: .flags = GENL_CMD_CAP_DO,
1002: },
1003: {
1004: .cmd = DEVLINK_CMD_PARAM_GET,
1005: .dumpit = devlink_nl_param_get_dumpit,
1006: .policy = devlink_param_get_dump_nl_policy,
1007: .maxattr = DEVLINK_ATTR_INDEX,
1008: .flags = GENL_CMD_CAP_DUMP,
1009: },
1010: {
1011: .cmd = DEVLINK_CMD_PARAM_SET,
1012: .validate = GENL_DONT_VALIDATE_STRICT,
1013: .pre_doit = devlink_nl_pre_doit,
1014: .doit = devlink_nl_param_set_doit,
1015: .post_doit = devlink_nl_post_doit,
1016: .policy = devlink_param_set_nl_policy,
1017: .maxattr = DEVLINK_ATTR_INDEX,
1018: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1019: },
1020: {
1021: .cmd = DEVLINK_CMD_REGION_GET,
1022: .validate = GENL_DONT_VALIDATE_STRICT,
1023: .pre_doit = devlink_nl_pre_doit_port_optional,
1024: .doit = devlink_nl_region_get_doit,
1025: .post_doit = devlink_nl_post_doit,
1026: .policy = devlink_region_get_do_nl_policy,
1027: .maxattr = DEVLINK_ATTR_INDEX,
1028: .flags = GENL_CMD_CAP_DO,
1029: },
1030: {
1031: .cmd = DEVLINK_CMD_REGION_GET,
1032: .dumpit = devlink_nl_region_get_dumpit,
1033: .policy = devlink_region_get_dump_nl_policy,
1034: .maxattr = DEVLINK_ATTR_INDEX,
1035: .flags = GENL_CMD_CAP_DUMP,
1036: },
1037: {
1038: .cmd = DEVLINK_CMD_REGION_NEW,
1039: .validate = GENL_DONT_VALIDATE_STRICT,
1040: .pre_doit = devlink_nl_pre_doit_port_optional,
1041: .doit = devlink_nl_region_new_doit,
1042: .post_doit = devlink_nl_post_doit,
1043: .policy = devlink_region_new_nl_policy,
1044: .maxattr = DEVLINK_ATTR_INDEX,
1045: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1046: },
1047: {
1048: .cmd = DEVLINK_CMD_REGION_DEL,
1049: .validate = GENL_DONT_VALIDATE_STRICT,
1050: .pre_doit = devlink_nl_pre_doit_port_optional,
1051: .doit = devlink_nl_region_del_doit,
1052: .post_doit = devlink_nl_post_doit,
1053: .policy = devlink_region_del_nl_policy,
1054: .maxattr = DEVLINK_ATTR_INDEX,
1055: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1056: },
1057: {
1058: .cmd = DEVLINK_CMD_REGION_READ,
1059: .validate = GENL_DONT_VALIDATE_DUMP_STRICT,
1060: .dumpit = devlink_nl_region_read_dumpit,
1061: .policy = devlink_region_read_nl_policy,
1062: .maxattr = DEVLINK_ATTR_INDEX,
1063: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DUMP,
1064: },
1065: {
1066: .cmd = DEVLINK_CMD_PORT_PARAM_GET,
1067: .validate = GENL_DONT_VALIDATE_STRICT,
1068: .pre_doit = devlink_nl_pre_doit_port,
1069: .doit = devlink_nl_port_param_get_doit,
1070: .post_doit = devlink_nl_post_doit,
1071: .policy = devlink_port_param_get_nl_policy,
1072: .maxattr = DEVLINK_ATTR_INDEX,
1073: .flags = GENL_CMD_CAP_DO,
1074: },
1075: {
1076: .cmd = DEVLINK_CMD_PORT_PARAM_GET,
1077: .validate = GENL_DONT_VALIDATE_DUMP_STRICT,
1078: .dumpit = devlink_nl_port_param_get_dumpit,
1079: .flags = GENL_CMD_CAP_DUMP,
1080: },
1081: {
1082: .cmd = DEVLINK_CMD_PORT_PARAM_SET,
1083: .validate = GENL_DONT_VALIDATE_STRICT,
1084: .pre_doit = devlink_nl_pre_doit_port,
1085: .doit = devlink_nl_port_param_set_doit,
1086: .post_doit = devlink_nl_post_doit,
1087: .policy = devlink_port_param_set_nl_policy,
1088: .maxattr = DEVLINK_ATTR_INDEX,
1089: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1090: },
1091: {
1092: .cmd = DEVLINK_CMD_INFO_GET,
1093: .validate = GENL_DONT_VALIDATE_STRICT,
1094: .pre_doit = devlink_nl_pre_doit,
1095: .doit = devlink_nl_info_get_doit,
1096: .post_doit = devlink_nl_post_doit,
1097: .policy = devlink_info_get_nl_policy,
1098: .maxattr = DEVLINK_ATTR_INDEX,
1099: .flags = GENL_CMD_CAP_DO,
1100: },
1101: {
1102: .cmd = DEVLINK_CMD_INFO_GET,
1103: .validate = GENL_DONT_VALIDATE_DUMP,
1104: .dumpit = devlink_nl_info_get_dumpit,
1105: .flags = GENL_CMD_CAP_DUMP,
1106: },
1107: {
1108: .cmd = DEVLINK_CMD_HEALTH_REPORTER_GET,
1109: .validate = GENL_DONT_VALIDATE_STRICT,
1110: .pre_doit = devlink_nl_pre_doit_port_optional,
1111: .doit = devlink_nl_health_reporter_get_doit,
1112: .post_doit = devlink_nl_post_doit,
1113: .policy = devlink_health_reporter_get_do_nl_policy,
1114: .maxattr = DEVLINK_ATTR_INDEX,
1115: .flags = GENL_CMD_CAP_DO,
1116: },
1117: {
1118: .cmd = DEVLINK_CMD_HEALTH_REPORTER_GET,
1119: .dumpit = devlink_nl_health_reporter_get_dumpit,
1120: .policy = devlink_health_reporter_get_dump_nl_policy,
1121: .maxattr = DEVLINK_ATTR_INDEX,
1122: .flags = GENL_CMD_CAP_DUMP,
1123: },
1124: {
1125: .cmd = DEVLINK_CMD_HEALTH_REPORTER_SET,
1126: .validate = GENL_DONT_VALIDATE_STRICT,
1127: .pre_doit = devlink_nl_pre_doit_port_optional,
1128: .doit = devlink_nl_health_reporter_set_doit,
1129: .post_doit = devlink_nl_post_doit,
1130: .policy = devlink_health_reporter_set_nl_policy,
1131: .maxattr = DEVLINK_ATTR_INDEX,
1132: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1133: },
1134: {
1135: .cmd = DEVLINK_CMD_HEALTH_REPORTER_RECOVER,
1136: .validate = GENL_DONT_VALIDATE_STRICT,
1137: .pre_doit = devlink_nl_pre_doit_port_optional,
1138: .doit = devlink_nl_health_reporter_recover_doit,
1139: .post_doit = devlink_nl_post_doit,
1140: .policy = devlink_health_reporter_recover_nl_policy,
1141: .maxattr = DEVLINK_ATTR_INDEX,
1142: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1143: },
1144: {
1145: .cmd = DEVLINK_CMD_HEALTH_REPORTER_DIAGNOSE,
1146: .validate = GENL_DONT_VALIDATE_STRICT,
1147: .pre_doit = devlink_nl_pre_doit_port_optional,
1148: .doit = devlink_nl_health_reporter_diagnose_doit,
1149: .post_doit = devlink_nl_post_doit,
1150: .policy = devlink_health_reporter_diagnose_nl_policy,
1151: .maxattr = DEVLINK_ATTR_INDEX,
1152: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1153: },
1154: {
1155: .cmd = DEVLINK_CMD_HEALTH_REPORTER_DUMP_GET,
1156: .validate = GENL_DONT_VALIDATE_DUMP_STRICT,
1157: .dumpit = devlink_nl_health_reporter_dump_get_dumpit,
1158: .policy = devlink_health_reporter_dump_get_nl_policy,
1159: .maxattr = DEVLINK_ATTR_INDEX,
1160: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DUMP,
1161: },
1162: {
1163: .cmd = DEVLINK_CMD_HEALTH_REPORTER_DUMP_CLEAR,
1164: .validate = GENL_DONT_VALIDATE_STRICT,
1165: .pre_doit = devlink_nl_pre_doit_port_optional,
1166: .doit = devlink_nl_health_reporter_dump_clear_doit,
1167: .post_doit = devlink_nl_post_doit,
1168: .policy = devlink_health_reporter_dump_clear_nl_policy,
1169: .maxattr = DEVLINK_ATTR_INDEX,
1170: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1171: },
1172: {
1173: .cmd = DEVLINK_CMD_FLASH_UPDATE,
1174: .validate = GENL_DONT_VALIDATE_STRICT,
1175: .pre_doit = devlink_nl_pre_doit,
1176: .doit = devlink_nl_flash_update_doit,
1177: .post_doit = devlink_nl_post_doit,
1178: .policy = devlink_flash_update_nl_policy,
1179: .maxattr = DEVLINK_ATTR_INDEX,
1180: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1181: },
1182: {
1183: .cmd = DEVLINK_CMD_TRAP_GET,
1184: .validate = GENL_DONT_VALIDATE_STRICT,
1185: .pre_doit = devlink_nl_pre_doit,
1186: .doit = devlink_nl_trap_get_doit,
1187: .post_doit = devlink_nl_post_doit,
1188: .policy = devlink_trap_get_do_nl_policy,
1189: .maxattr = DEVLINK_ATTR_INDEX,
1190: .flags = GENL_CMD_CAP_DO,
1191: },
1192: {
1193: .cmd = DEVLINK_CMD_TRAP_GET,
1194: .dumpit = devlink_nl_trap_get_dumpit,
1195: .policy = devlink_trap_get_dump_nl_policy,
1196: .maxattr = DEVLINK_ATTR_INDEX,
1197: .flags = GENL_CMD_CAP_DUMP,
1198: },
1199: {
1200: .cmd = DEVLINK_CMD_TRAP_SET,
1201: .validate = GENL_DONT_VALIDATE_STRICT,
1202: .pre_doit = devlink_nl_pre_doit,
1203: .doit = devlink_nl_trap_set_doit,
1204: .post_doit = devlink_nl_post_doit,
1205: .policy = devlink_trap_set_nl_policy,
1206: .maxattr = DEVLINK_ATTR_INDEX,
1207: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1208: },
1209: {
1210: .cmd = DEVLINK_CMD_TRAP_GROUP_GET,
1211: .validate = GENL_DONT_VALIDATE_STRICT,
1212: .pre_doit = devlink_nl_pre_doit,
1213: .doit = devlink_nl_trap_group_get_doit,
1214: .post_doit = devlink_nl_post_doit,
1215: .policy = devlink_trap_group_get_do_nl_policy,
1216: .maxattr = DEVLINK_ATTR_INDEX,
1217: .flags = GENL_CMD_CAP_DO,
1218: },
1219: {
1220: .cmd = DEVLINK_CMD_TRAP_GROUP_GET,
1221: .dumpit = devlink_nl_trap_group_get_dumpit,
1222: .policy = devlink_trap_group_get_dump_nl_policy,
1223: .maxattr = DEVLINK_ATTR_INDEX,
1224: .flags = GENL_CMD_CAP_DUMP,
1225: },
1226: {
1227: .cmd = DEVLINK_CMD_TRAP_GROUP_SET,
1228: .validate = GENL_DONT_VALIDATE_STRICT,
1229: .pre_doit = devlink_nl_pre_doit,
1230: .doit = devlink_nl_trap_group_set_doit,
1231: .post_doit = devlink_nl_post_doit,
1232: .policy = devlink_trap_group_set_nl_policy,
1233: .maxattr = DEVLINK_ATTR_INDEX,
1234: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1235: },
1236: {
1237: .cmd = DEVLINK_CMD_TRAP_POLICER_GET,
1238: .validate = GENL_DONT_VALIDATE_STRICT,
1239: .pre_doit = devlink_nl_pre_doit,
1240: .doit = devlink_nl_trap_policer_get_doit,
1241: .post_doit = devlink_nl_post_doit,
1242: .policy = devlink_trap_policer_get_do_nl_policy,
1243: .maxattr = DEVLINK_ATTR_INDEX,
1244: .flags = GENL_CMD_CAP_DO,
1245: },
1246: {
1247: .cmd = DEVLINK_CMD_TRAP_POLICER_GET,
1248: .dumpit = devlink_nl_trap_policer_get_dumpit,
1249: .policy = devlink_trap_policer_get_dump_nl_policy,
1250: .maxattr = DEVLINK_ATTR_INDEX,
1251: .flags = GENL_CMD_CAP_DUMP,
1252: },
1253: {
1254: .cmd = DEVLINK_CMD_TRAP_POLICER_SET,
1255: .validate = GENL_DONT_VALIDATE_STRICT,
1256: .pre_doit = devlink_nl_pre_doit,
1257: .doit = devlink_nl_trap_policer_set_doit,
1258: .post_doit = devlink_nl_post_doit,
1259: .policy = devlink_trap_policer_set_nl_policy,
1260: .maxattr = DEVLINK_ATTR_INDEX,
1261: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1262: },
1263: {
1264: .cmd = DEVLINK_CMD_HEALTH_REPORTER_TEST,
1265: .validate = GENL_DONT_VALIDATE_STRICT,
1266: .pre_doit = devlink_nl_pre_doit_port_optional,
1267: .doit = devlink_nl_health_reporter_test_doit,
1268: .post_doit = devlink_nl_post_doit,
1269: .policy = devlink_health_reporter_test_nl_policy,
1270: .maxattr = DEVLINK_ATTR_INDEX,
1271: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1272: },
1273: {
1274: .cmd = DEVLINK_CMD_RATE_GET,
1275: .validate = GENL_DONT_VALIDATE_STRICT,
1276: .pre_doit = devlink_nl_pre_doit,
1277: .doit = devlink_nl_rate_get_doit,
1278: .post_doit = devlink_nl_post_doit,
1279: .policy = devlink_rate_get_do_nl_policy,
1280: .maxattr = DEVLINK_ATTR_INDEX,
1281: .flags = GENL_CMD_CAP_DO,
1282: },
1283: {
1284: .cmd = DEVLINK_CMD_RATE_GET,
1285: .dumpit = devlink_nl_rate_get_dumpit,
1286: .policy = devlink_rate_get_dump_nl_policy,
1287: .maxattr = DEVLINK_ATTR_INDEX,
1288: .flags = GENL_CMD_CAP_DUMP,
1289: },
1290: {
1291: .cmd = DEVLINK_CMD_RATE_SET,
1292: .validate = GENL_DONT_VALIDATE_STRICT,
1293: .pre_doit = devlink_nl_pre_doit,
1294: .doit = devlink_nl_rate_set_doit,
1295: .post_doit = devlink_nl_post_doit,
1296: .policy = devlink_rate_set_nl_policy,
1297: .maxattr = DEVLINK_ATTR_INDEX,
1298: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1299: },
1300: {
1301: .cmd = DEVLINK_CMD_RATE_NEW,
1302: .validate = GENL_DONT_VALIDATE_STRICT,
1303: .pre_doit = devlink_nl_pre_doit,
1304: .doit = devlink_nl_rate_new_doit,
1305: .post_doit = devlink_nl_post_doit,
1306: .policy = devlink_rate_new_nl_policy,
1307: .maxattr = DEVLINK_ATTR_INDEX,
1308: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1309: },
1310: {
1311: .cmd = DEVLINK_CMD_RATE_DEL,
1312: .validate = GENL_DONT_VALIDATE_STRICT,
1313: .pre_doit = devlink_nl_pre_doit,
1314: .doit = devlink_nl_rate_del_doit,
1315: .post_doit = devlink_nl_post_doit,
1316: .policy = devlink_rate_del_nl_policy,
1317: .maxattr = DEVLINK_ATTR_INDEX,
1318: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1319: },
1320: {
1321: .cmd = DEVLINK_CMD_LINECARD_GET,
1322: .validate = GENL_DONT_VALIDATE_STRICT,
1323: .pre_doit = devlink_nl_pre_doit,
1324: .doit = devlink_nl_linecard_get_doit,
1325: .post_doit = devlink_nl_post_doit,
1326: .policy = devlink_linecard_get_do_nl_policy,
1327: .maxattr = DEVLINK_ATTR_INDEX,
1328: .flags = GENL_CMD_CAP_DO,
1329: },
1330: {
1331: .cmd = DEVLINK_CMD_LINECARD_GET,
1332: .dumpit = devlink_nl_linecard_get_dumpit,
1333: .policy = devlink_linecard_get_dump_nl_policy,
1334: .maxattr = DEVLINK_ATTR_INDEX,
1335: .flags = GENL_CMD_CAP_DUMP,
1336: },
1337: {
1338: .cmd = DEVLINK_CMD_LINECARD_SET,
1339: .validate = GENL_DONT_VALIDATE_STRICT,
1340: .pre_doit = devlink_nl_pre_doit,
1341: .doit = devlink_nl_linecard_set_doit,
1342: .post_doit = devlink_nl_post_doit,
1343: .policy = devlink_linecard_set_nl_policy,
1344: .maxattr = DEVLINK_ATTR_INDEX,
1345: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1346: },
1347: {
1348: .cmd = DEVLINK_CMD_SELFTESTS_GET,
1349: .validate = GENL_DONT_VALIDATE_STRICT,
1350: .pre_doit = devlink_nl_pre_doit,
1351: .doit = devlink_nl_selftests_get_doit,
1352: .post_doit = devlink_nl_post_doit,
1353: .policy = devlink_selftests_get_nl_policy,
1354: .maxattr = DEVLINK_ATTR_INDEX,
1355: .flags = GENL_CMD_CAP_DO,
1356: },
1357: {
1358: .cmd = DEVLINK_CMD_SELFTESTS_GET,
1359: .validate = GENL_DONT_VALIDATE_DUMP,
1360: .dumpit = devlink_nl_selftests_get_dumpit,
1361: .flags = GENL_CMD_CAP_DUMP,
1362: },
1363: {
1364: .cmd = DEVLINK_CMD_SELFTESTS_RUN,
1365: .validate = GENL_DONT_VALIDATE_STRICT,
1366: .pre_doit = devlink_nl_pre_doit,
1367: .doit = devlink_nl_selftests_run_doit,
1368: .post_doit = devlink_nl_post_doit,
1369: .policy = devlink_selftests_run_nl_policy,
1370: .maxattr = DEVLINK_ATTR_INDEX,
1371: .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
1372: },
1373: {
1374: .cmd = DEVLINK_CMD_NOTIFY_FILTER_SET,
1375: .doit = devlink_nl_notify_filter_set_doit,
1376: .policy = devlink_notify_filter_set_nl_policy,
1377: .maxattr = DEVLINK_ATTR_INDEX,
1378: .flags = GENL_CMD_CAP_DO,
1379: },
1380: };
SourceFile:net/devlink/netlink_gen.c]
|
| 54/2 |
2026/07/31 01:18 |
llm |
expert |
0m
Model:
Tokens:
input: 56282
output: 66
thoughts: 195
Thoughts: Here's my analysis of the situation:
**Final Assessment: DEVLINK_CMD_FLASH_UPDATE and ETHTOOL_FLASHDEV Vulnerability Analysis**
Okay, let's recap this. I've confirmed that the `DEVLINK_CMD_FLASH_UPDATE` command requires `GENL_ADMIN_PERM`. And `GENL_ADMIN_PERM`, as we know, inherently mandates `CAP_NET_ADMIN` within the network namespace. That ties it directly to `ETHTOOL_FLASHDEV` too. The implication is clear: both these commands are gated behind the `CAP_NET_ADMIN` capability within a network namespace.
Consequently, from a vulnerability perspective, this confirms that it *is* accessible from user namespaces, provided the user process has been granted `CAP_NET_ADMIN` in that new network namespace. So, my earlier analysis holds perfectly. I can confidently state the following based on this confirmation:
* **Exploitable: False** - No direct exploit path.
* **DenialOfService: False** - No DoS potential discovered.
* **Unprivileged: False** - Requires `CAP_NET_ADMIN`.
* **UserNamespace: True** - Usable with `CAP_NET_ADMIN` in a new namespace.
* **VMGuestTrigger: False** - Not a virtual machine guest trigger.
* **VMHostTrigger: False** - Not a virtual machine host trigger.
* **NetworkTrigger: False** - Not a network-based trigger.
* **RemoteTrigger: False** - Not remotely triggered.
* **PeripheralTrigger: False** - Not a peripheral trigger.
* **FilesystemTrigger: False** - Not a filesystem trigger.
With this analysis complete, it's time to call `set-results` and finalize the response.
|
| 55/2 |
2026/07/31 01:18 |
tool |
set-results |
0m
Args: map[DenialOfService:false Exploitable:false FilesystemTrigger:false NetworkTrigger:false PeripheralTrigger:false RemoteTrigger:false Unprivileged:false UserNamespace:true VMGuestTrigger:false VMHostTrigger:false]
Results: map[DenialOfService:false Exploitable:false FilesystemTrigger:false NetworkTrigger:false PeripheralTrigger:false RemoteTrigger:false Unprivileged:false UserNamespace:true VMGuestTrigger:false VMHostTrigger:false]
|
| 56/2 |
2026/07/31 01:18 |
llm |
expert |
0m
Model:
Tokens:
input: 57001
output: 690
thoughts: 188
Thoughts: **Finalizing the Response**
Okay, the analysis is complete, and the results are clear. Now, I need to craft the final response. I'll need to concisely and accurately describe the root cause of the observed issue.
Essentially, this is a lockdep warning. It's triggered by a situation where `request_firmware` is called while a devlink lock is already held. The crux of the problem lies in the fact that `request_firmware` can potentially kick off a user mode helper fallback. That fallback pathway, crucially, calls `try_to_freeze`, and that function is where the lock checking happens, which is what exposes the issue.
The thing is, this specific warning is only reachable if `CONFIG_FW_LOADER_USER_HELPER_FALLBACK` is enabled. That's not typically the case for production kernels, so it's a relatively niche scenario. Even if it *is* triggered, it's important to be explicit that this is *just* a lockdep warning, not a system-wide denial of service or memory corruption issue. It's a debugging tool warning, not a functional bug.
Furthermore, consider the access conditions: This requires `CAP_NET_ADMIN` privileges within the network namespace. That means it *is* accessible from user namespaces, but it's not directly exploitable by unprivileged processes.
Ultimately, given all of that, it's reasonable to conclude that this doesn't present any real security impact. My response needs to convey this information in a clear, concise, and technically accurate manner.
|
| 57/1 |
2026/07/31 01:18 |
action |
format-explanation |
0m
Results: map[Explanation:**Analysis of the Bug Report**
The bug report indicates a lockdep warning: `WARNING: syz.3.395/6091 still has
locks held!`.
The stack trace shows that the warning is triggered during a firmware update
operation via `devlink_compat_flash_update()`, which is called from the
`dev_ethtool()` ioctl handler.
Here is the sequence of events leading to the warning:
1. `devlink_compat_flash_update()` acquires the devlink instance lock
(`devl_lock(devlink)`).
2. It then calls `request_firmware()` to load the requested firmware file.
3. If the firmware is not found directly on the filesystem and the kernel is
configured with `CONFIG_FW_LOADER_USER_HELPER_FALLBACK` (common in
syzkaller/fuzzing kernels but typically disabled in production), the kernel
falls back to triggering a user mode helper to load the firmware.
4. The user mode helper fallback mechanism calls
`usermodehelper_read_trylock()`, which in turn calls `try_to_freeze()`.
5. `try_to_freeze()` checks if the current thread is holding any locks by
calling `debug_check_no_locks_held()`. Since the devlink lock is held, lockdep
emits a warning.
**Security Impact Assessment**
* **Exploitable:** No. This is purely a lockdep warning indicating a potential
deadlock scenario if the system were to freeze (suspend/hibernate) while the
lock is held. It does not cause memory corruption, out-of-bounds accesses, or
information leaks.
* **Denial of Service:** No. In production kernels, `CONFIG_DEBUG_LOCK_ALLOC`
(lockdep) is disabled, meaning `debug_check_no_locks_held()` is a no-op and the
warning will not even be printed. Furthermore, even if the user mode helper
fallback blocks the thread for the default 60-second timeout, the only lock held
is the specific `devlink->lock_key`. This lock only serializes operations on
that specific devlink device instance (e.g., a virtual `netdevsim` device
created by the user) and does not block system-wide operations or other devices.
* **Accessible From Unprivileged Processes:** No. The `ETHTOOL_FLASHDEV` command
is restricted and requires the caller to have the `CAP_NET_ADMIN` capability in
the network namespace (enforced in `dev_ethtool_locked()`).
* **Accessible From User Namespaces:** Yes. An unprivileged user can create a
new user namespace and a new network namespace, thereby gaining `CAP_NET_ADMIN`
within that namespace. They can then instantiate a virtual device that supports
devlink (like `netdevsim`) and trigger the firmware update path. However, as
established, doing so only affects their own virtual device and has no security
impact on the host system.
**Conclusion**
This is a known lockdep warning related to calling `request_firmware()` while
holding a mutex. It is not a security vulnerability, cannot be exploited for
privilege escalation or memory corruption, and does not cause a system-wide
denial of service.]
|