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KCSAN: data-race in __d_lookup / __d_rehash (8)

Status: auto-obsoleted due to no activity on 2024/09/19 14:50
Subsystems: ext4
[Documentation on labels]
Reported-by: syzbot+da75324df105e629d3e7@syzkaller.appspotmail.com
First crash: 269d, last: 152d
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __d_lookup / __d_rehash (6) fs 1 508d 508d 0/28 auto-obsoleted due to no activity on 2023/09/29 22:29
upstream KCSAN: data-race in __d_lookup / __d_rehash (4) ext4 1 626d 626d 0/28 auto-obsoleted due to no activity on 2023/06/04 03:50
upstream KCSAN: data-race in __d_lookup / __d_rehash fs 1 1887d 1887d 0/28 auto-closed as invalid on 2020/01/24 17:56
upstream KCSAN: data-race in __d_lookup / __d_rehash (3) fs 1 797d 797d 0/28 auto-obsoleted due to no activity on 2022/12/14 23:50
upstream KCSAN: data-race in __d_lookup / __d_rehash (2) fs 1 990d 990d 0/28 auto-closed as invalid on 2022/06/04 08:25
upstream KCSAN: data-race in __d_lookup / __d_rehash (9) fs 2 3d09h 18d 0/28 moderation: reported on 2024/12/27 23:19
upstream KCSAN: data-race in __d_lookup / __d_rehash (5) ext4 2 566d 567d 0/28 auto-obsoleted due to no activity on 2023/08/02 16:55
upstream KCSAN: data-race in __d_lookup / __d_rehash (7) ext4 1 461d 461d 0/28 auto-obsoleted due to no activity on 2023/11/15 16:47

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __d_lookup / __d_rehash

write to 0xffff8881068e5a90 of 8 bytes by task 3261 on cpu 1:
 hlist_bl_add_head_rcu include/linux/rculist_bl.h:81 [inline]
 __d_rehash+0xa9/0x210 fs/dcache.c:2412
 __d_add+0x373/0x4a0 fs/dcache.c:2627
 d_splice_alias+0xd6/0x270 fs/dcache.c:3018
 proc_sys_lookup+0x386/0x440 fs/proc/proc_sysctl.c:534
 lookup_open fs/namei.c:3556 [inline]
 open_last_lookups fs/namei.c:3647 [inline]
 path_openat+0xc5f/0x1f10 fs/namei.c:3883
 do_filp_open+0xf7/0x200 fs/namei.c:3913
 do_sys_openat2+0xab/0x120 fs/open.c:1416
 do_sys_open fs/open.c:1431 [inline]
 __do_sys_openat fs/open.c:1447 [inline]
 __se_sys_openat fs/open.c:1442 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1442
 x64_sys_call+0x1025/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881068e5a90 of 8 bytes by task 3262 on cpu 0:
 hlist_bl_unhashed include/linux/list_bl.h:54 [inline]
 d_unhashed include/linux/dcache.h:354 [inline]
 __d_lookup+0xf1/0x370 fs/dcache.c:2324
 lookup_fast+0x4c/0x2a0 fs/namei.c:1676
 open_last_lookups fs/namei.c:3615 [inline]
 path_openat+0x466/0x1f10 fs/namei.c:3883
 do_filp_open+0xf7/0x200 fs/namei.c:3913
 do_sys_openat2+0xab/0x120 fs/open.c:1416
 do_sys_open fs/open.c:1431 [inline]
 __do_sys_openat fs/open.c:1447 [inline]
 __se_sys_openat fs/open.c:1442 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1442
 x64_sys_call+0x1025/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff888237439bf0 -> 0xffff8881068e6488

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3262 Comm: syz-executor Not tainted 6.11.0-rc3-syzkaller-00060-gd07b43284ab3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
==================================================================
chnl_net:caif_netlink_parms(): no params data found
bridge0: port 1(bridge_slave_0) entered blocking state
bridge0: port 1(bridge_slave_0) entered disabled state
bridge_slave_0: entered allmulticast mode
bridge_slave_0: entered promiscuous mode
bridge0: port 2(bridge_slave_1) entered blocking state
bridge0: port 2(bridge_slave_1) entered disabled state
bridge_slave_1: entered allmulticast mode
bridge_slave_1: entered promiscuous mode
bond0: (slave bond_slave_0): Enslaving as an active interface with an up link
bond0: (slave bond_slave_1): Enslaving as an active interface with an up link
team0: Port device team_slave_0 added
team0: Port device team_slave_1 added
batman_adv: batadv0: Adding interface: batadv_slave_0
batman_adv: batadv0: The MTU of interface batadv_slave_0 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
batman_adv: batadv0: Not using interface batadv_slave_0 (retrying later): interface not active
batman_adv: batadv0: Adding interface: batadv_slave_1
batman_adv: batadv0: The MTU of interface batadv_slave_1 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
batman_adv: batadv0: Not using interface batadv_slave_1 (retrying later): interface not active
hsr_slave_0: entered promiscuous mode
hsr_slave_1: entered promiscuous mode
debugfs: Directory 'hsr0' with parent 'hsr' already present!
Cannot create hsr debugfs directory
netdevsim netdevsim4 netdevsim0: renamed from eth0
netdevsim netdevsim4 netdevsim1: renamed from eth1
netdevsim netdevsim4 netdevsim2: renamed from eth2
netdevsim netdevsim4 netdevsim3: renamed from eth3
8021q: adding VLAN 0 to HW filter on device bond0
8021q: adding VLAN 0 to HW filter on device team0
8021q: adding VLAN 0 to HW filter on device batadv0
veth0_vlan: entered promiscuous mode
veth1_vlan: entered promiscuous mode
veth0_macvtap: entered promiscuous mode
veth1_macvtap: entered promiscuous mode
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_0
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_0
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_0
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_0
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: batadv0: Interface activated: batadv_slave_0
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3f) already exists on: batadv_slave_1
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3f) already exists on: batadv_slave_1
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3f) already exists on: batadv_slave_1
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3f) already exists on: batadv_slave_1
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: batadv0: Interface activated: batadv_slave_1
netdevsim netdevsim4 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim4 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim4 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim4 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/15 14:49 upstream d07b43284ab3 e4bacdaf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __d_lookup / __d_rehash
2024/08/10 00:19 upstream afdab700f65e a83d9288 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __d_lookup / __d_rehash
2024/08/08 07:51 upstream 6a0e38264012 de12cf65 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __d_lookup / __d_rehash
2024/07/31 04:19 upstream 22f546873149 6fde257d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __d_lookup / __d_rehash
2024/07/20 16:20 upstream 3c3ff7be9729 b88348e9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __d_lookup / __d_rehash
2024/06/18 04:36 upstream 14d7c92f8df9 ce6011bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __d_lookup / __d_rehash
2024/05/22 18:26 upstream 2a8120d7b482 4d098039 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __d_lookup / __d_rehash
2024/04/20 12:08 upstream 13a2e429f644 af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __d_lookup / __d_rehash
* Struck through repros no longer work on HEAD.