syzbot


KCSAN: data-race in fill_mg_cmtime / shmem_unlink

Status: moderation: reported on 2024/11/19 16:50
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+981e2f2af3b7fc150759@syzkaller.appspotmail.com
First crash: 173d, last: 13h48m

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

write to 0xffff888104450c94 of 4 bytes by task 3306 on cpu 0:
 inode_set_mtime_to_ts include/linux/fs.h:1706 [inline]
 shmem_unlink+0x13c/0x170 mm/shmem.c:3974
 shmem_rename2+0x1a1/0x290 mm/shmem.c:4063
 vfs_rename+0x7d6/0xa20 fs/namei.c:5121
 do_renameat2+0x764/0xab0 fs/namei.c:5270
 __do_sys_rename fs/namei.c:5317 [inline]
 __se_sys_rename fs/namei.c:5315 [inline]
 __x64_sys_rename+0x58/0x70 fs/namei.c:5315
 x64_sys_call+0x2aee/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:83
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888104450c94 of 4 bytes by task 3309 on cpu 1:
 inode_get_mtime_nsec include/linux/fs.h:1692 [inline]
 inode_get_mtime include/linux/fs.h:1698 [inline]
 fill_mg_cmtime+0x5b/0x260 fs/stat.c:55
 generic_fillattr+0x24a/0x340 fs/stat.c:99
 shmem_getattr+0x181/0x200 mm/shmem.c:1262
 vfs_getattr_nosec+0x143/0x1e0 fs/stat.c:210
 vfs_getattr fs/stat.c:259 [inline]
 vfs_statx_path fs/stat.c:296 [inline]
 vfs_statx+0x11a/0x380 fs/stat.c:353
 vfs_fstatat+0xe1/0x160 fs/stat.c:372
 __do_sys_newfstatat fs/stat.c:536 [inline]
 __se_sys_newfstatat+0x55/0x260 fs/stat.c:530
 __x64_sys_newfstatat+0x55/0x70 fs/stat.c:530
 x64_sys_call+0x2c22/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:263
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x066d18bd -> 0x0672b0a3

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3309 Comm: udevd Not tainted 6.15.0-rc5-syzkaller-00353-gcd802e7e5f1e #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
==================================================================

Crashes (50):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/11 20:34 upstream cd802e7e5f1e 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/05/04 10:06 upstream e8ab83e34bdc b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/04/29 07:50 upstream f15d97df5afa aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/04/24 13:35 upstream a79be02bba5c 9882047a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/04/24 03:23 upstream a79be02bba5c 73a168d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/04/17 00:00 upstream c62f4b82d571 a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/04/14 07:06 upstream 8ffd015db85f 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/04/09 09:55 upstream a24588245776 47d015b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/04/07 12:59 upstream 0af2f6be1b42 a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/04/05 00:57 upstream a52a3c18cdf3 1c4febdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/04/01 01:10 upstream 1e7857b28020 d3999433 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/03/21 09:36 upstream b3ee1e460951 62330552 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/03/20 19:01 upstream 5fc319360819 62330552 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/03/20 19:01 upstream 5fc319360819 62330552 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/03/10 03:33 upstream 80e54e84911a 163f510d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/03/08 21:23 upstream 2a520073e74f 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/03/08 01:02 upstream 00a7d39898c8 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/03/01 16:43 upstream 03d38806a902 c3901742 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/03/01 08:43 upstream 7a5668899f54 67cf5345 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/02/22 20:56 upstream 5cf80612d3f7 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/02/18 17:54 upstream 2408a807bfc3 c37c7249 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/02/16 08:24 upstream ad1b832bf1cf 40a34ec9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/02/12 04:11 upstream 09fbf3d50205 f2baddf5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/02/11 10:43 upstream febbc555cf0f 43f51a00 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/02/07 07:02 upstream bb066fe812d6 53657d1b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/02/07 00:05 upstream bb066fe812d6 8002dd28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/02/02 03:09 upstream cabb4685d57e 568559e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/02/01 07:40 upstream 60c828cf80c0 aa47157c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/01/31 20:08 upstream 69b8923f5003 aa47157c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/01/31 17:48 upstream 69e858e0b8b2 aa47157c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/01/30 02:40 upstream ebbb8be421ee afe4eff5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/01/28 12:24 upstream 6d61a53dd6f5 f5427d7c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/01/27 14:08 upstream 9c5968db9e62 d99a33ad .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/01/15 18:04 upstream 619f0b6fad52 968edaf4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/01/06 10:23 upstream 9d89551994a4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2025/01/04 19:42 upstream ab75170520d4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/12/30 08:30 upstream fc033cf25e61 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/12/20 06:27 upstream 8faabc041a00 0f61b415 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/12/15 12:17 upstream 2d8308bf5b67 7cbfbb3a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/12/14 13:27 upstream a446e965a188 7cbfbb3a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/12/13 18:45 upstream 243f750a2df0 3547e30f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/12/13 07:18 upstream 150b567e0d57 3547e30f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/12/12 14:45 upstream 231825b2e1ff 530e80f8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/12/09 10:56 upstream fac04efc5c79 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/12/08 19:50 upstream 62b5a46999c7 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/12/01 22:12 upstream f788b5ef1ca9 68914665 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/11/29 19:30 upstream 509f806f7f70 5df23865 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/11/28 21:17 upstream 7af08b57bcb9 5df23865 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/11/23 21:03 upstream 42d9e8b7ccdd 68da6d95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
2024/11/19 16:49 upstream 158f238aa69d 7d02db5a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fill_mg_cmtime / shmem_unlink
* Struck through repros no longer work on HEAD.