syzbot


KCSAN: data-race in shrink_dentry_list / step_into (6)

Status: auto-obsoleted due to no activity on 2024/03/03 06:03
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+d7455a83ef563674225f@syzkaller.appspotmail.com
First crash: 77d, last: 77d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in shrink_dentry_list / step_into fs 1 900d 900d 0/26 auto-closed as invalid on 2021/12/01 04:11
upstream KCSAN: data-race in shrink_dentry_list / step_into (7) fs 1 21d 21d 0/26 moderation: reported on 2024/03/24 15:55
upstream KCSAN: data-race in shrink_dentry_list / step_into (5) fs 3 195d 234d 0/26 auto-obsoleted due to no activity on 2023/11/06 20:19
upstream KCSAN: data-race in shrink_dentry_list / step_into (2) fs 3 580d 605d 0/26 auto-obsoleted due to no activity on 2022/10/17 16:38
upstream KCSAN: data-race in shrink_dentry_list / step_into (3) fs 1 537d 537d 0/26 auto-obsoleted due to no activity on 2022/11/29 05:37
upstream KCSAN: data-race in shrink_dentry_list / step_into (4) fs 1 475d 475d 0/26 auto-obsoleted due to no activity on 2023/02/06 16:11

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

read-write to 0xffff8881006c8a80 of 4 bytes by task 5152 on cpu 0:
 d_shrink_del fs/dcache.c:449 [inline]
 shrink_dentry_list+0x19f/0x3d0 fs/dcache.c:1074
 shrink_dcache_sb+0x165/0x290 fs/dcache.c:1195
 reconfigure_super+0x3ef/0x580 fs/super.c:1054
 do_remount fs/namespace.c:2892 [inline]
 path_mount+0x969/0xb30 fs/namespace.c:3671
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3875
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3875
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff8881006c8a80 of 4 bytes by task 5153 on cpu 1:
 __follow_mount_rcu fs/namei.c:1486 [inline]
 handle_mounts fs/namei.c:1537 [inline]
 step_into+0xe7/0x800 fs/namei.c:1839
 walk_component fs/namei.c:2007 [inline]
 link_path_walk+0x4d8/0x7e0 fs/namei.c:2328
 path_lookupat+0x72/0x2a0 fs/namei.c:2481
 filename_lookup+0x126/0x300 fs/namei.c:2511
 vfs_statx+0xa2/0x320 fs/stat.c:244
 vfs_fstatat+0xcd/0x100 fs/stat.c:304
 __do_sys_newfstatat fs/stat.c:468 [inline]
 __se_sys_newfstatat+0x58/0x260 fs/stat.c:462
 __x64_sys_newfstatat+0x55/0x60 fs/stat.c:462
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x00680440 -> 0x00008040

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5153 Comm: modprobe Not tainted 6.8.0-rc1-syzkaller-00331-gcd2286fc5775 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/01/28 06:03 upstream cd2286fc5775 cc4a4020 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in shrink_dentry_list / step_into
* Struck through repros no longer work on HEAD.