BUG: unable to handle kernel NULL pointer dereference in getname_kernel

Status: upstream: reported C repro on 2026/09/08 01:21
Subsystems: fs
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+6c46a179b56c651c4c96@syzkaller.appspotmail.com
First crash: 46d, last: 23d
▶ ▼ ✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
a82649b1 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ BUG: unable to handle kernel NULL pointer dereference in getname_kernel 2026/09/08 00:41 2026/09/08 00:41 2026/09/08 01:09 680aa3e1
▶ ▼ Discussions (2)
Title Replies (including bot) Last reply
[PATCH] nvmet: validate device_path before enabling namespace 3 (3) 2026/09/09 08:11
[syzbot] [fs?] BUG: unable to handle kernel NULL pointer dereference in getname_kernel 0 (2) 2026/09/08 17:58
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in getname_kernel (2) btrfs 2 syz, C done 17 739d 743d 0/29 auto-obsoleted due to no activity on 2024/11/22 15:11
linux-6.1 BUG: unable to handle kernel paging request in getname_kernel 8 syz, C 155 17h14m 79d 0/3 upstream: reported C repro on 2026/08/04 20:01
linux-6.6 general protection fault in getname_kernel origin:lts-only 2 syz, C 39 3d16h 77d 0/2 upstream: reported C repro on 2026/08/07 04:10
upstream KASAN: slab-out-of-bounds Read in getname_kernel (2) btrfs 17 syz, C done 5 992d 1039d 25/29 fixed on 2024/03/28 13:58
▶ ▼ Last patch testing requests (5)
Created Duration User Patch Repo Result
2026/10/13 15:30 36m retest repro https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master no crash job log log
2026/10/13 15:30 34m retest repro https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master no crash job log log
2026/10/13 15:30 34m retest repro https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master no crash job log log
2026/10/13 15:30 35m retest repro https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master no crash job log log
2026/09/08 17:58 35m pavankumaryalagada@gmail.com patch https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux 73ae59e97596 OK job log log

Sample crash report:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Mem abort info:
  ESR = 0x0000000096000006
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x06: level 2 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000006, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0
user pgtable: 4k pages, 52-bit VAs, pgdp=0000000043ecb080
[0000000000000000] pgd=0800000059e9a403, p4d=0800000049c68403, pud=080000009a457403, pmd=0000000000000000
Internal error: Oops: 0000000096000006 [#1]  SMP
Modules linked in:
CPU: 1 UID: 0 PID: 30888 Comm: syz.6.9504 Tainted: G        W    L      syzkaller #0 PREEMPT 
Tainted: [W]=WARN, [L]=SOFTLOCKUP
Hardware name: linux,dummy-virt (DT)
pstate: 61402009 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : __pi_strlen+0x14/0x150 arch/arm64/lib/strlen.S:87
lr : __fortify_strlen include/linux/fortify-string.h:218 [inline]
lr : do_getname_kernel+0x20/0x12c fs/namei.c:260
sp : ffff800089843b60
x29: ffff800089843b60 x28: f3f0000016de2200 x27: 0000000000000000
x26: 0000000000000000 x25: 0000000000000000 x24: f5f0000014d715c0
x23: f5f0000014e95800 x22: 0000000000000000 x21: 0000000000000000
x20: 00000000fffffff1 x19: 0000000000020002 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 00000000200004c0
x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
x8 : 0101010101010101 x7 : f5f0000014d715c8 x6 : f0f0000037ee8001
x5 : f0f0000037ee8001 x4 : 0000000000000000 x3 : f3f0000016de2200
x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
 __pi_strlen+0x14/0x150 arch/arm64/lib/strlen.S:86 (P)
 getname_kernel+0x14/0x20 fs/namei.c:289
 class_filename_kernel_constructor include/linux/fs.h:2586 [inline]
 filp_open+0x34/0x104 fs/open.c:1391
 nvmet_file_ns_enable+0x38/0xfc drivers/nvme/target/io-cmd-file.c:41
 nvmet_ns_enable+0x12c/0x1e0 drivers/nvme/target/core.c:596
 nvmet_ns_enable_store+0x64/0xd4 drivers/nvme/target/configfs.c:737
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0xc4/0x128 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x244/0x36c fs/read_write.c:687
 ksys_write+0x70/0x108 fs/read_write.c:739
 __do_sys_write fs/read_write.c:750 [inline]
 __se_sys_write fs/read_write.c:747 [inline]
 __arm64_sys_write+0x18/0x24 fs/read_write.c:747
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x54/0x10c arch/arm64/kernel/syscall.c:49
 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x1c/0x34 arch/arm64/kernel/syscall.c:140
 el0_svc+0x38/0x1fc arch/arm64/kernel/entry-common.c:758
 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:777
 el0t_64_sync+0x1a4/0x1a8 arch/arm64/kernel/entry.S:590
Code: 92400c04 b200c3e8 f100009f 5400088c (a9400c02) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	92400c04 	and	x4, x0, #0xf
   4:	b200c3e8 	mov	x8, #0x101010101010101     	// #72340172838076673
   8:	f100009f 	cmp	x4, #0x0
   c:	5400088c 	b.gt	0x11c
* 10:	a9400c02 	ldp	x2, x3, [x0] <-- trapping instruction

Crashes (17):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/29 15:18 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 45c13f3f9e3b 7bf4ea23 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/23 12:57 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 abce1216 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/23 12:57 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 abce1216 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/23 01:09 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 3e2106e5 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/23 01:09 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 3e2106e5 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/19 01:32 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 853b104b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/19 01:31 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 853b104b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/10 19:19 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 1fe56c0a .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/10 19:18 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 1fe56c0a .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/07 19:17 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 5e4626f5 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/07 19:17 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 5e4626f5 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/07 09:12 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 4f7b22a0 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/07 07:25 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 4f7b22a0 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/07 05:41 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 4f7b22a0 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/07 03:58 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 4f7b22a0 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/07 02:11 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 4f7b22a0 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
2026/09/07 02:10 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 4f7b22a0 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in getname_kernel
* Struck through repros no longer work on HEAD.