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KCSAN: data-race in shrink_dentry_list / step_into (2)

Status: auto-obsoleted due to no activity on 2022/10/17 16:38
Subsystems: fs
[Documentation on labels]
First crash: 640d, last: 615d
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 (6) fs 1 112d 112d 0/26 auto-obsoleted due to no activity on 2024/03/03 06:03
upstream KCSAN: data-race in shrink_dentry_list / step_into fs 1 935d 935d 0/26 auto-closed as invalid on 2021/12/01 04:11
upstream KCSAN: data-race in shrink_dentry_list / step_into (7) fs 2 21d 56d 0/26 moderation: reported on 2024/03/24 15:55
upstream KCSAN: data-race in shrink_dentry_list / step_into (5) fs 3 229d 269d 0/26 auto-obsoleted due to no activity on 2023/11/06 20:19
upstream KCSAN: data-race in shrink_dentry_list / step_into (3) fs 1 572d 572d 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 510d 510d 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 0xffff88811a60c6c0 of 4 bytes by task 6943 on cpu 1:
 d_shrink_del fs/dcache.c:448 [inline]
 shrink_dentry_list+0x1cf/0x380 fs/dcache.c:1188
 shrink_dcache_sb+0x16d/0x2b0 fs/dcache.c:1321
 reconfigure_super+0x146/0x540 fs/super.c:917
 do_remount fs/namespace.c:2702 [inline]
 path_mount+0xa11/0xbb0 fs/namespace.c:3362
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x281/0x2d0 fs/namespace.c:3568
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88811a60c6c0 of 4 bytes by task 1824 on cpu 0:
 __follow_mount_rcu fs/namei.c:1480 [inline]
 handle_mounts fs/namei.c:1531 [inline]
 step_into+0xdc/0x7d0 fs/namei.c:1831
 walk_component fs/namei.c:1999 [inline]
 link_path_walk+0x53e/0x8a0 fs/namei.c:2320
 path_lookupat+0x7b/0x2b0 fs/namei.c:2473
 filename_lookup+0x133/0x310 fs/namei.c:2503
 vfs_statx+0xa3/0x3d0 fs/stat.c:228
 vfs_fstatat fs/stat.c:255 [inline]
 vfs_lstat include/linux/fs.h:3282 [inline]
 __do_sys_newlstat fs/stat.c:411 [inline]
 __se_sys_newlstat+0x6a/0x270 fs/stat.c:405
 __x64_sys_newlstat+0x2d/0x40 fs/stat.c:405
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00280440 -> 0x00200040

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1824 Comm: syz-executor.5 Not tainted 6.0.0-rc5-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/09/12 16:31 upstream 80e78fcce86d f371ed7e .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in shrink_dentry_list / step_into
2022/09/01 02:40 upstream c5e4d5e99162 b01ec571 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in shrink_dentry_list / step_into
2022/08/18 07:39 upstream 274a2eebf80c a9409d47 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in shrink_dentry_list / step_into
* Struck through repros no longer work on HEAD.