syzbot


KCSAN: data-race in inode_set_ctime_to_ts / inode_update_timestamps

Status: moderation: reported on 2024/12/07 03:44
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+5bb7e024098072fa0406@syzkaller.appspotmail.com
First crash: 14d, last: 14d

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

write to 0xffff888106b9aed8 of 8 bytes by task 7698 on cpu 0:
 inode_set_ctime_to_ts+0x73/0x180 fs/inode.c:2715
 inode_set_ctime_current+0x1b7/0x7a0 fs/inode.c:2779
 inode_update_timestamps+0x85/0x250 fs/inode.c:2066
 generic_update_time fs/inode.c:2105 [inline]
 inode_update_time fs/inode.c:2125 [inline]
 __file_update_time fs/inode.c:2353 [inline]
 file_update_time+0x219/0x2b0 fs/inode.c:2383
 pipe_write+0xa7b/0xd20 fs/pipe.c:607
 new_sync_write fs/read_write.c:586 [inline]
 vfs_write+0x77f/0x920 fs/read_write.c:679
 ksys_write+0xe8/0x1b0 fs/read_write.c:731
 __do_sys_write fs/read_write.c:742 [inline]
 __se_sys_write fs/read_write.c:739 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:739
 x64_sys_call+0x287e/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:2
 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 0xffff888106b9aed8 of 8 bytes by task 7692 on cpu 1:
 inode_get_ctime_sec include/linux/fs.h:1673 [inline]
 inode_get_ctime include/linux/fs.h:1683 [inline]
 inode_update_timestamps+0x43/0x250 fs/inode.c:2063
 generic_update_time fs/inode.c:2105 [inline]
 inode_update_time fs/inode.c:2125 [inline]
 __file_update_time fs/inode.c:2353 [inline]
 file_update_time+0x219/0x2b0 fs/inode.c:2383
 pipe_write+0xa7b/0xd20 fs/pipe.c:607
 new_sync_write fs/read_write.c:586 [inline]
 vfs_write+0x77f/0x920 fs/read_write.c:679
 ksys_write+0xe8/0x1b0 fs/read_write.c:731
 __do_sys_write fs/read_write.c:742 [inline]
 __se_sys_write fs/read_write.c:739 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:739
 x64_sys_call+0x287e/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:2
 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: 0x000000006753c475 -> 0x000000006753c476

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 7692 Comm: syz.5.1244 Not tainted 6.13.0-rc1-syzkaller-00239-g9a6e8c7c3a02 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/07 03:44 upstream 9a6e8c7c3a02 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in inode_set_ctime_to_ts / inode_update_timestamps
* Struck through repros no longer work on HEAD.