syzbot


KCSAN: data-race in dont_mount / step_into

Status: moderation: reported syz repro on 2022/05/07 00:44
Subsystems: isofs
[Documentation on labels]
Reported-by: syzbot+7ab22e852c066cf2af27@syzkaller.appspotmail.com
First crash: 1196d, last: 5h08m

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

read-write to 0xffff888109362c00 of 4 bytes by task 3337 on cpu 0:
 dont_mount+0x27/0x40 include/linux/dcache.h:363
 vfs_unlink+0x298/0x430 fs/namei.c:4345
 do_unlinkat+0x236/0x4c0 fs/namei.c:4407
 __do_sys_unlink fs/namei.c:4455 [inline]
 __se_sys_unlink fs/namei.c:4453 [inline]
 __x64_sys_unlink+0x30/0x40 fs/namei.c:4453
 x64_sys_call+0x28a3/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:88
 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 0xffff888109362c00 of 4 bytes by task 2786 on cpu 1:
 __follow_mount_rcu fs/namei.c:1485 [inline]
 handle_mounts fs/namei.c:1536 [inline]
 step_into+0xe7/0x810 fs/namei.c:1842
 walk_component+0x169/0x230 fs/namei.c:2010
 lookup_last fs/namei.c:2469 [inline]
 path_lookupat+0x10a/0x2b0 fs/namei.c:2493
 filename_lookup+0x127/0x300 fs/namei.c:2522
 user_path_at_empty+0x42/0x120 fs/namei.c:2929
 do_readlinkat+0x92/0x210 fs/stat.c:499
 __do_sys_readlink fs/stat.c:532 [inline]
 __se_sys_readlink fs/stat.c:529 [inline]
 __x64_sys_readlink+0x47/0x60 fs/stat.c:529
 x64_sys_call+0x264b/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:90
 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: 0x00600008 -> 0x00008008

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 2786 Comm: udevd Not tainted 6.10.0-rc4-syzkaller-00045-g92e5605a199e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
==================================================================

Crashes (1784):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/19 16:38 upstream 92e5605a199e 41b7e219 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/16 20:47 upstream 155a3c003e55 44f8051e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/16 07:14 upstream 155a3c003e55 124ec9cc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/14 09:43 upstream 347e9f5043c8 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/13 21:22 upstream 5d5d62298b8b 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/12 21:28 upstream 3f31a806a62e 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/12 08:04 upstream 379f604cc3dc 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/10 18:33 upstream bc9ff192a6c9 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/09 22:32 upstream 8c2e52ebbe88 f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/09 09:18 upstream 733923397fd9 f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/09 06:40 upstream 733923397fd9 4d9fdfa4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/08 18:01 upstream d006330be3f7 4d9fdfa4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/06 10:38 upstream 1f988d0788f5 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/05 20:43 upstream 05df91921da6 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/05 06:42 upstream a79a588fc176 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/04 17:53 upstream 4c06e63b9203 d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/04 11:37 upstream 4c06e63b9203 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/03 22:42 upstream 17bbde2e1716 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/03 17:02 upstream 17bbde2e1716 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/03 04:26 upstream b4911fb0b060 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/02 18:46 upstream b4911fb0b060 bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/07/01 17:42 upstream 66701750d556 091a06cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/30 17:15 upstream d0b3b7b22dfa 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/30 07:47 upstream d0b3b7b22dfa fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/29 12:00 upstream dfba48a70cb6 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/29 01:45 upstream ded779017ad7 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/27 22:08 upstream 67a993863163 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/27 02:54 upstream f02769e7f272 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/26 13:16 upstream ee88bddf7f2f 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/26 08:32 upstream ee88bddf7f2f 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/23 23:52 upstream 78f4e737a53e e2f27c35 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/23 10:00 upstream 86731a2a651e d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/22 05:39 upstream 739a6c93cc75 d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/21 16:49 upstream 3f75bfff44be d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/21 03:07 upstream 11313e2f7812 d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/20 12:22 upstream 75f5f23f8787 804b3919 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/20 07:57 upstream 75f5f23f8787 ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/19 17:46 upstream 24770983ccfe ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/19 03:20 upstream fb4d33ab452e ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/19 00:13 upstream 52da431bf03b ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/18 11:53 upstream 52da431bf03b ca631f70 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/18 08:52 upstream 52da431bf03b e77fae15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/17 23:00 upstream 4663747812d1 e77fae15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/17 03:31 upstream 9afe652958c3 cfebc887 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2025/06/15 05:56 upstream 8c6bc74c7f89 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2022/05/06 23:52 upstream 64267926e01b e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2022/05/06 21:37 upstream 64267926e01b e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
2022/04/07 05:11 upstream 3e732ebf7316 53c67432 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in dont_mount / step_into
* Struck through repros no longer work on HEAD.