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KCSAN: data-race in shrink_dentry_list / step_into (5)

Status: auto-obsoleted due to no activity on 2023/11/06 20:19
Subsystems: fs
[Documentation on labels]
First crash: 269d, last: 229d
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 (2) fs 3 615d 640d 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 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 0xffff8881066f7e40 of 4 bytes by task 26618 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:1118
 do_remount fs/namespace.c:2882 [inline]
 path_mount+0x969/0xb30 fs/namespace.c:3654
 do_mount fs/namespace.c:3675 [inline]
 __do_sys_mount fs/namespace.c:3884 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3861
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3861
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff8881066f7e40 of 4 bytes by task 26609 on cpu 1:
 __d_entry_type include/linux/dcache.h:385 [inline]
 d_is_symlink include/linux/dcache.h:415 [inline]
 step_into+0x12f/0x800 fs/namei.c:1844
 walk_component+0x164/0x230 fs/namei.c:2007
 lookup_last fs/namei.c:2458 [inline]
 path_lookupat+0x10a/0x2a0 fs/namei.c:2482
 filename_lookup+0x126/0x300 fs/namei.c:2511
 kern_path+0x39/0x100 fs/namei.c:2609
 do_loopback+0x65/0x2d0 fs/namespace.c:2611
 path_mount+0x3cb/0xb30 fs/namespace.c:3656
 do_mount fs/namespace.c:3675 [inline]
 __do_sys_mount fs/namespace.c:3884 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3861
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3861
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00290400 -> 0x00210000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 26609 Comm: syz-executor.4 Not tainted 6.6.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/10/02 20:18 upstream 8a749fd1a872 50b20e75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in shrink_dentry_list / step_into
2023/08/29 17:03 upstream 1c59d383390f 7ba13a15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in shrink_dentry_list / step_into
2023/08/24 10:16 upstream a5e505a99ca7 4d7ae7ab .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.