syzbot


KCSAN: data-race in strscpy / strscpy (2)

Status: auto-obsoleted due to no activity on 2022/12/11 17:10
Subsystems: ext4
[Documentation on labels]
First crash: 649d, last: 507d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in strscpy / strscpy fs mm 1 707d 707d 0/26 auto-closed as invalid on 2022/05/25 16:47
upstream KCSAN: data-race in strscpy / strscpy (3) ext4 mm 3 357d 342d 22/26 fixed on 2023/06/08 14:41

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

write to 0xffff88814e6d1388 of 8 bytes by task 15969 on cpu 1:
 strscpy+0xa8/0x170 lib/string.c:218
 strscpy_pad+0x23/0x80 lib/string_helpers.c:835
 __set_task_comm+0x3b/0x110 fs/exec.c:1233
 set_task_comm include/linux/sched.h:1984 [inline]
 __kthread_create_on_node+0x2aa/0x320 kernel/kthread.c:474
 kthread_create_on_node+0x86/0xb0 kernel/kthread.c:512
 init_rescuer+0x10e/0x190 kernel/workqueue.c:4272
 alloc_workqueue+0x7c3/0xa70 kernel/workqueue.c:4347
 __ext4_fill_super fs/ext4/super.c:5369 [inline]
 ext4_fill_super+0x3758/0x4560 fs/ext4/super.c:5643
 get_tree_bdev+0x2b4/0x3b0 fs/super.c:1324
 ext4_get_tree+0x18/0x20 fs/ext4/super.c:5673
 vfs_get_tree+0x49/0x190 fs/super.c:1531
 do_new_mount+0x200/0x650 fs/namespace.c:3040
 path_mount+0x4aa/0xb70 fs/namespace.c:3370
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x281/0x2d0 fs/namespace.c:3568
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88814e6d138d of 1 bytes by task 15973 on cpu 0:
 strscpy+0xdf/0x170 lib/string.c:227
 ____bpf_get_current_comm kernel/bpf/helpers.c:258 [inline]
 bpf_get_current_comm+0x42/0x70 kernel/bpf/helpers.c:250
 ___bpf_prog_run+0x278/0x2da0 kernel/bpf/core.c:1818
 __bpf_prog_run32+0x70/0xa0 kernel/bpf/core.c:2041
 bpf_dispatcher_nop_func include/linux/bpf.h:964 [inline]
 __bpf_prog_run include/linux/filter.h:600 [inline]
 bpf_prog_run include/linux/filter.h:607 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2254 [inline]
 bpf_trace_run4+0x98/0x150 kernel/trace/bpf_trace.c:2295
 __traceiter_sched_switch+0x45/0x60 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x6c1/0x6e0 kernel/sched/core.c:6500
 schedule+0x51/0x80 kernel/sched/core.c:6579
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6638
 kthread+0x129/0x1e0 kernel/kthread.c:369
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306

value changed: 0x61 -> 0x72

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 15973 Comm: ext4-rsv-conver Not tainted 6.1.0-rc3-syzkaller-00299-g2f5065a0bc9d-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
==================================================================

Crashes (13):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/11/06 16:59 upstream 2f5065a0bc9d 6d752409 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
2022/10/27 10:49 upstream 4dc12f37a8e9 86777b7f .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
2022/10/05 10:40 upstream 0326074ff465 267e3bb1 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
2022/09/21 01:37 upstream 60891ec99e14 c4b8ccfd .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
2022/09/20 01:16 upstream 521a547ced64 dd9a85ff .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
2022/09/19 00:00 upstream 38eddeedbbea dd9a85ff .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
2022/09/03 00:57 upstream 0b3acd1cc022 25194605 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
2022/08/21 12:41 upstream 15b3f48a4339 26a13b38 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
2022/08/03 23:48 upstream ff89dd08c0f0 1c9013ac .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
2022/07/09 15:12 upstream e5524c2a1fc4 b5765a15 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
2022/07/05 16:08 upstream c1084b6c5620 bff65f44 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
2022/07/01 16:48 upstream a175eca0f3d7 1434eec0 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
2022/06/18 05:48 upstream 462abc9de7a1 8f633d84 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in strscpy / strscpy
* Struck through repros no longer work on HEAD.