syzbot


KCSAN: data-race in evdev_pass_values / evdev_poll (12)

Status: moderation: reported on 2025/08/27 20:57
Subsystems: input
[Documentation on labels]
Reported-by: syzbot+cb962545025ba25fcb26@syzkaller.appspotmail.com
First crash: 257d, last: 7d11h
✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision Error
e4f94fef-e8da-4b42-8bac-a5ced60415cc repro 💥 KCSAN: data-race in evdev_pass_values / evdev_poll (12) 2026/03/10 12:38 2026/03/10 12:38 2026/03/10 12:45 5c03941b7fba0fd3b0326afc981322c89fe9ba52+ failed to run ["git" "pull" "origin" "HEAD" "--depth=1" "--allow-unrelated-histories"]: exit status 1
48e8d962-ba53-4810-9ca3-074f40ddd133 assessment-kcsan Benign: ✅ Confident: ✅ KCSAN: data-race in evdev_pass_values / evdev_poll (12) 2026/01/14 17:41 2026/01/14 17:41 2026/01/14 18:01 a9d6a79219801d2130df3b1a792c57f0e5428e9f
Similar bugs (11)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in evdev_pass_values / evdev_poll (10) input 6 2 504d 506d 0/29 auto-obsoleted due to no activity on 2025/02/17 08:57
upstream KCSAN: data-race in evdev_pass_values / evdev_poll (3) input 6 2 1296d 1309d 0/29 auto-obsoleted due to no activity on 2022/11/27 08:01
upstream KCSAN: data-race in evdev_pass_values / evdev_poll (11) input 6 2 359d 365d 0/29 auto-obsoleted due to no activity on 2025/07/12 11:09
upstream KCSAN: data-race in evdev_pass_values / evdev_poll (8) input 6 1 772d 772d 0/29 auto-obsoleted due to no activity on 2024/05/04 08:18
upstream KCSAN: data-race in evdev_pass_values / evdev_poll (9) input 6 6 697d 725d 0/29 auto-obsoleted due to no activity on 2024/07/18 19:14
upstream KCSAN: data-race in evdev_pass_values / evdev_poll input 6 65 1417d 1664d 0/29 auto-closed as invalid on 2022/07/29 11:48
upstream KCSAN: data-race in evdev_pass_values / evdev_poll (5) input 6 16 1055d 1087d 0/29 auto-obsoleted due to no activity on 2023/07/27 03:31
upstream KCSAN: data-race in evdev_pass_values / evdev_poll (4) input 6 7 1218d 1242d 0/29 auto-obsoleted due to no activity on 2023/03/10 09:08
upstream KCSAN: data-race in evdev_pass_values / evdev_poll (7) input 6 5 870d 883d 0/29 auto-obsoleted due to no activity on 2024/01/28 04:16
upstream KCSAN: data-race in evdev_pass_values / evdev_poll (6) input 6 5 978d 997d 0/29 auto-obsoleted due to no activity on 2023/10/11 10:42
upstream KCSAN: data-race in evdev_pass_values / evdev_poll (2) input 6 2 1350d 1352d 0/29 auto-closed as invalid on 2022/10/04 21:56

Sample crash report:
==================================================================
BUG: KCSAN: data-race in evdev_pass_values / evdev_poll

write to 0xffff888103b42008 of 4 bytes by task 11230 on cpu 1:
 __pass_event drivers/input/evdev.c:239 [inline]
 evdev_pass_values+0x387/0x4e0 drivers/input/evdev.c:278
 evdev_events+0x8e/0xd0 drivers/input/evdev.c:306
 input_pass_values+0x123/0x390 drivers/input/input.c:128
 input_event_dispose+0x248/0x320 drivers/input/input.c:342
 input_handle_event+0x9e8/0xa20 drivers/input/input.c:370
 input_inject_event+0xba/0x100 drivers/input/input.c:424
 evdev_write+0x224/0x2b0 drivers/input/evdev.c:528
 vfs_write+0x269/0x9f0 fs/read_write.c:686
 ksys_write+0xdc/0x1a0 fs/read_write.c:740
 __do_sys_write fs/read_write.c:751 [inline]
 __se_sys_write fs/read_write.c:748 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:748
 x64_sys_call+0x27e1/0x3020 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888103b42008 of 4 bytes by task 2966 on cpu 0:
 evdev_poll+0xc4/0x100 drivers/input/evdev.c:621
 vfs_poll include/linux/poll.h:82 [inline]
 select_poll_one fs/select.c:480 [inline]
 do_select+0x94e/0xfa0 fs/select.c:536
 core_sys_select+0x45d/0x730 fs/select.c:677
 do_pselect fs/select.c:759 [inline]
 __do_sys_pselect6 fs/select.c:798 [inline]
 __se_sys_pselect6+0x23c/0x2a0 fs/select.c:789
 __x64_sys_pselect6+0x78/0x90 fs/select.c:789
 x64_sys_call+0x8d5/0x3020 arch/x86/include/generated/asm/syscalls_64.h:271
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000007 -> 0x00000009

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 2966 Comm: acpid Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
==================================================================

Crashes (10):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/04 18:46 upstream 6d35786de281 85f1bcf2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in evdev_pass_values / evdev_poll
2026/04/07 11:39 upstream bfe62a454542 628666c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in evdev_pass_values / evdev_poll
2026/03/27 06:26 upstream 46b513250491 766b6434 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in evdev_pass_values / evdev_poll
2026/02/08 14:39 upstream e7aa57247700 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in evdev_pass_values / evdev_poll
2026/01/19 13:10 upstream 24d479d26b25 a9fc5226 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in evdev_pass_values / evdev_poll
2026/01/13 06:04 upstream b71e635feefc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in evdev_pass_values / evdev_poll
2025/11/20 02:57 upstream 23cb64fb7625 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in evdev_pass_values / evdev_poll
2025/10/14 03:03 upstream 3a8660878839 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in evdev_pass_values / evdev_poll
2025/09/04 01:43 upstream ec299e4dc21e 96a211bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in evdev_pass_values / evdev_poll
2025/08/27 20:57 upstream 39f90c196721 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in evdev_pass_values / evdev_poll
* Struck through repros no longer work on HEAD.