syzbot


KCSAN: data-race in do_sys_poll / pollwake

Status: moderation: reported on 2020/07/18 20:22
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+a5d15da12b55f807031f@syzkaller.appspotmail.com
First crash: 1854d, last: 5h53m

Sample crash report:
==================================================================
BUG: KCSAN: data-race in do_sys_poll / pollwake

write to 0xffffc90002137bc0 of 4 bytes by interrupt on cpu 0:
 __pollwake fs/select.c:195 [inline]
 pollwake+0xb6/0x100 fs/select.c:215
 __wake_up_common kernel/sched/wait.c:89 [inline]
 __wake_up_common_lock kernel/sched/wait.c:106 [inline]
 __wake_up+0x66/0xb0 kernel/sched/wait.c:127
 bpf_ringbuf_notify+0x22/0x30 kernel/bpf/ringbuf.c:155
 irq_work_single kernel/irq_work.c:221 [inline]
 irq_work_run_list kernel/irq_work.c:252 [inline]
 irq_work_run+0xe2/0x2d0 kernel/irq_work.c:261
 __sysvec_irq_work+0x22/0x170 arch/x86/kernel/irq_work.c:22
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0x66/0x80 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738
 __wrmsrq arch/x86/include/asm/msr.h:80 [inline]
 native_write_msr arch/x86/include/asm/msr.h:137 [inline]
 wrmsrq arch/x86/include/asm/msr.h:199 [inline]
 native_apic_msr_write+0x3d/0x60 arch/x86/include/asm/apic.h:212
 apic_write arch/x86/include/asm/apic.h:405 [inline]
 x2apic_send_IPI_self+0x10/0x20 arch/x86/kernel/apic/x2apic_phys.c:107
 __apic_send_IPI_self arch/x86/include/asm/apic.h:455 [inline]
 arch_irq_work_raise+0x46/0x50 arch/x86/kernel/irq_work.c:31
 irq_work_raise kernel/irq_work.c:84 [inline]
 __irq_work_queue_local+0x10f/0x2c0 kernel/irq_work.c:112
 irq_work_queue+0x70/0x100 kernel/irq_work.c:124
 bpf_ringbuf_commit kernel/bpf/ringbuf.c:-1 [inline]
 ____bpf_ringbuf_discard kernel/bpf/ringbuf.c:525 [inline]
 bpf_ringbuf_discard+0xd3/0xf0 kernel/bpf/ringbuf.c:523
 bpf_prog_fe0ed97373b08409+0x4b/0x4f
 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2258 [inline]
 bpf_trace_run3+0x10f/0x1d0 kernel/trace/bpf_trace.c:2300
 __traceiter_kmem_cache_free+0x35/0x60 include/trace/events/kmem.h:114
 __do_trace_kmem_cache_free include/trace/events/kmem.h:114 [inline]
 trace_kmem_cache_free include/trace/events/kmem.h:114 [inline]
 kmem_cache_free+0x257/0x300 mm/slub.c:4744
 __d_free fs/dcache.c:345 [inline]
 dentry_free fs/dcache.c:440 [inline]
 __dentry_kill+0x3d1/0x4b0 fs/dcache.c:688
 dput+0x5e/0xd0 fs/dcache.c:911
 __fput+0x444/0x650 fs/file_table.c:473
 ____fput+0x1c/0x30 fs/file_table.c:493
 task_work_run+0x131/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe4/0x100 kernel/entry/common.c:114
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffc90002137bc0 of 4 bytes by task 20156 on cpu 1:
 poll_schedule_timeout fs/select.c:240 [inline]
 do_poll fs/select.c:958 [inline]
 do_sys_poll+0x99c/0xbd0 fs/select.c:1009
 __do_sys_ppoll fs/select.c:1115 [inline]
 __se_sys_ppoll+0x1b9/0x200 fs/select.c:1095
 __x64_sys_ppoll+0x67/0x80 fs/select.c:1095
 x64_sys_call+0x2de5/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:272
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 20156 Comm: syz.8.6755 Not tainted 6.16.0-rc6-syzkaller-00037-ge2291551827f #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
==================================================================

Crashes (5305):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/17 14:35 upstream e2291551827f 0d1223f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/17 01:25 upstream e2291551827f 44f8051e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/16 20:48 upstream 155a3c003e55 44f8051e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/16 08:08 upstream 155a3c003e55 124ec9cc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/15 04:25 upstream 155a3c003e55 03fcfc4b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/14 11:06 upstream 347e9f5043c8 d8fc7335 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/14 08:43 upstream 347e9f5043c8 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/12 22:07 upstream 3f31a806a62e 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/11 19:41 upstream 40f92e79b0aa 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/10 02:43 upstream 8c2e52ebbe88 956bd956 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/09 22:59 upstream 8c2e52ebbe88 f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/09 09:58 upstream 733923397fd9 f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/08 18:54 upstream d006330be3f7 4d9fdfa4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/08 15:28 upstream d7b8f8e20813 4d9fdfa4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/06 10:44 upstream 1f988d0788f5 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/05 21:18 upstream 05df91921da6 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/05 06:49 upstream a79a588fc176 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/04 15:09 upstream 4c06e63b9203 d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/04 12:18 upstream 4c06e63b9203 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/03 22:31 upstream 17bbde2e1716 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/03 05:52 upstream b4911fb0b060 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/02 20:02 upstream b4911fb0b060 bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/02 04:07 upstream 66701750d556 bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/01 14:45 upstream 66701750d556 091a06cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/07/01 01:35 upstream 66701750d556 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/30 18:04 upstream d0b3b7b22dfa 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/30 02:21 upstream d0b3b7b22dfa fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/29 12:05 upstream dfba48a70cb6 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/28 23:46 upstream ded779017ad7 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/27 23:00 upstream 67a993863163 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/27 16:52 upstream 67a993863163 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/27 03:16 upstream f02769e7f272 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/26 09:20 upstream ee88bddf7f2f 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/25 01:19 upstream 7595b66ae9de 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/23 23:53 upstream 78f4e737a53e e2f27c35 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/23 22:38 upstream 86731a2a651e e2f27c35 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/23 10:23 upstream 86731a2a651e d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/22 21:29 upstream b67ec639010f d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/22 06:08 upstream 739a6c93cc75 d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/21 16:08 upstream 3f75bfff44be d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/21 02:22 upstream 11313e2f7812 d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/20 07:52 upstream 75f5f23f8787 ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/18 14:21 upstream 52da431bf03b ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/18 12:34 upstream 52da431bf03b ca631f70 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2025/06/18 09:24 upstream 52da431bf03b e77fae15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_sys_poll / pollwake
2021/01/17 10:56 upstream 0da0a8a0a0e1 813be542 .config console log report info ci2-upstream-kcsan-gce
2020/07/18 19:22 upstream 6cf7ccba29dc 9c812472 .config console log report ci2-upstream-kcsan-gce
2020/07/14 20:16 upstream e9919e11e219 6f458026 .config console log report ci2-upstream-kcsan-gce
2020/06/19 12:55 upstream 5e857ce6eae7 bc258b50 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.