syzbot


KCSAN: data-race in generic_fillattr / inode_update_timestamps (3)

Status: moderation: reported on 2024/11/26 05:44
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+45b8a8c3f7a9139f15b4@syzkaller.appspotmail.com
First crash: 17h41m, last: 17h41m
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in generic_fillattr / inode_update_timestamps fs 2 358d 351d 0/28 auto-obsoleted due to no activity on 2024/01/09 18:18
upstream KCSAN: data-race in generic_fillattr / inode_update_timestamps (2) fs 4 304d 320d 0/28 auto-obsoleted due to no activity on 2024/03/02 19:43

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

write to 0xffff8881014469a4 of 4 bytes by task 15129 on cpu 1:
 inode_set_mtime_to_ts include/linux/fs.h:1648 [inline]
 inode_update_timestamps+0x139/0x250 fs/inode.c:2070
 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
 blkdev_write_iter+0x31d/0x460 block/fops.c:711
 do_iter_readv_writev+0x394/0x450
 vfs_writev+0x2d4/0x880 fs/read_write.c:1050
 do_pwritev fs/read_write.c:1146 [inline]
 __do_sys_pwritev2 fs/read_write.c:1204 [inline]
 __se_sys_pwritev2+0x100/0x1c0 fs/read_write.c:1195
 __x64_sys_pwritev2+0x78/0x90 fs/read_write.c:1195
 x64_sys_call+0x2afe/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:329
 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 0xffff8881014469a4 of 4 bytes by task 13922 on cpu 0:
 inode_get_mtime_nsec include/linux/fs.h:1634 [inline]
 inode_get_mtime include/linux/fs.h:1640 [inline]
 generic_fillattr+0x205/0x330 fs/stat.c:102
 shmem_getattr+0x17b/0x200 mm/shmem.c:1177
 vfs_getattr_nosec fs/stat.c:208 [inline]
 vfs_getattr fs/stat.c:246 [inline]
 vfs_fstat+0x19d/0x200 fs/stat.c:265
 vfs_fstatat fs/stat.c:364 [inline]
 __do_sys_newfstatat fs/stat.c:530 [inline]
 __se_sys_newfstatat+0xb5/0x300 fs/stat.c:524
 __x64_sys_newfstatat+0x55/0x70 fs/stat.c:524
 x64_sys_call+0x236d/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:263
 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: 0x0d379c01 -> 0x10765517

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 13922 Comm: udevd Not tainted 6.12.0-syzkaller-09435-g2c22dc1ee3a1 #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
2024/11/26 05:43 upstream 2c22dc1ee3a1 11dbc254 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_fillattr / inode_update_timestamps
* Struck through repros no longer work on HEAD.