syzbot


KCSAN: data-race in link_path_walk / shrink_dentry_list (10)

Status: auto-obsoleted due to no activity on 2024/02/06 05:32
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+99a8d5e57fe3d6ecb61a@syzkaller.appspotmail.com
First crash: 242d, last: 197d
Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in link_path_walk / shrink_dentry_list (5) fs 1 856d 856d 0/27 auto-closed as invalid on 2022/04/17 20:20
upstream KCSAN: data-race in link_path_walk / shrink_dentry_list (6) fs 1 795d 795d 0/27 auto-closed as invalid on 2022/06/18 02:44
upstream KCSAN: data-race in link_path_walk / shrink_dentry_list (8) fs 1 521d 521d 0/27 auto-obsoleted due to no activity on 2023/04/09 05:58
upstream KCSAN: data-race in link_path_walk / shrink_dentry_list (4) fs 10 892d 1029d 0/27 auto-closed as invalid on 2022/03/12 22:14
upstream KCSAN: data-race in link_path_walk / shrink_dentry_list (2) fs 3 1151d 1185d 0/27 auto-closed as invalid on 2021/06/27 19:17
upstream KCSAN: data-race in link_path_walk / shrink_dentry_list (7) fs 1 718d 718d 0/27 auto-closed as invalid on 2022/09/03 00:29
upstream KCSAN: data-race in link_path_walk / shrink_dentry_list (11) fs 1 37d 37d 0/27 auto-obsoleted due to no activity on 2024/07/15 02:37
upstream KCSAN: data-race in link_path_walk / shrink_dentry_list (3) fs 2 1064d 1069d 0/27 auto-closed as invalid on 2021/09/22 09:34
upstream KCSAN: data-race in link_path_walk / shrink_dentry_list (9) fs 1 288d 288d 0/27 auto-obsoleted due to no activity on 2023/11/07 05:43
upstream KCSAN: data-race in link_path_walk / shrink_dentry_list fs 1 1459d 1459d 0/27 auto-closed as invalid on 2020/08/23 06:27

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

read-write to 0xffff8881d1601840 of 4 bytes by task 21839 on cpu 0:
 d_shrink_del fs/dcache.c:448 [inline]
 shrink_dentry_list+0x1c7/0x380 fs/dcache.c:1188
 shrink_dcache_sb+0x165/0x290 fs/dcache.c:1321
 reconfigure_super+0x3ef/0x580 fs/super.c:1121
 do_remount fs/namespace.c:2884 [inline]
 path_mount+0x969/0xb30 fs/namespace.c:3656
 do_mount fs/namespace.c:3677 [inline]
 __do_sys_mount fs/namespace.c:3886 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3863
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3863
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff8881d1601840 of 4 bytes by task 21831 on cpu 1:
 __d_entry_type include/linux/dcache.h:386 [inline]
 d_can_lookup include/linux/dcache.h:401 [inline]
 link_path_walk+0x4fc/0x7e0 fs/namei.c:2339
 path_lookupat+0x72/0x2a0 fs/namei.c:2482
 filename_lookup+0x126/0x300 fs/namei.c:2512
 kern_path+0x39/0x110 fs/namei.c:2610
 do_loopback+0x65/0x2d0 fs/namespace.c:2613
 path_mount+0x3cb/0xb30 fs/namespace.c:3658
 do_mount fs/namespace.c:3677 [inline]
 __do_sys_mount fs/namespace.c:3886 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3863
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3863
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x00280400 -> 0x00200000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 21831 Comm: syz-executor.1 Not tainted 6.7.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/01/02 05:32 upstream 610a9b8f49fb fb427a07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in link_path_walk / shrink_dentry_list
2023/12/22 14:28 upstream 24e0d2e527a3 4f9530a3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in link_path_walk / shrink_dentry_list
2023/11/17 22:33 upstream 6bc40e44f1dd cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in link_path_walk / shrink_dentry_list
* Struck through repros no longer work on HEAD.