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

Status: auto-obsoleted due to no activity on 2023/05/09 19:03
Subsystems: fs
[Documentation on labels]
First crash: 864d, last: 864d
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in dentry_lru_isolate_shrink / step_into (4) fs 6 1 601d 601d 0/29 auto-obsoleted due to no activity on 2024/01/27 20:26
upstream KCSAN: data-race in dentry_lru_isolate_shrink / step_into (3) fs 6 1 697d 697d 0/29 auto-obsoleted due to no activity on 2023/10/23 22:54
upstream KCSAN: data-race in dentry_lru_isolate_shrink / step_into fs 6 1 1579d 1579d 0/29 auto-closed as invalid on 2021/05/24 08:11

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

write to 0xffff88810abb36c0 of 4 bytes by task 25956 on cpu 1:
 d_lru_shrink_move fs/dcache.c:480 [inline]
 dentry_lru_isolate_shrink+0x7f/0x100 fs/dcache.c:1300
 __list_lru_walk_one+0x180/0x3b0 mm/list_lru.c:231
 list_lru_walk_node+0x14d/0x1f0 mm/list_lru.c:316
 list_lru_walk include/linux/list_lru.h:214 [inline]
 shrink_dcache_sb+0xc5/0x290 fs/dcache.c:1319
 reconfigure_super+0x273/0x540 fs/super.c:939
 do_remount fs/namespace.c:2704 [inline]
 path_mount+0xa2a/0xb40 fs/namespace.c:3364
 do_mount fs/namespace.c:3385 [inline]
 __do_sys_mount fs/namespace.c:3594 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3571
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3571
 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 0xffff88810abb36c0 of 4 bytes by task 25949 on cpu 0:
 __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:1837
 walk_component+0x164/0x230 fs/namei.c:2000
 lookup_last fs/namei.c:2451 [inline]
 path_lookupat+0x10a/0x2a0 fs/namei.c:2475
 filename_lookup+0x126/0x300 fs/namei.c:2504
 user_path_at_empty+0x42/0x110 fs/namei.c:2877
 user_path_at include/linux/namei.h:57 [inline]
 __do_sys_open_tree fs/namespace.c:2539 [inline]
 __se_sys_open_tree+0x156/0x580 fs/namespace.c:2506
 __x64_sys_open_tree+0x43/0x50 fs/namespace.c:2506
 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: 0x00680000 -> 0x00008000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 25949 Comm: syz-executor.1 Not tainted 6.3.0-rc5-syzkaller-00005-g148341f0a2f5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/04 18:52 upstream 148341f0a2f5 928dd177 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in dentry_lru_isolate_shrink / step_into
* Struck through repros no longer work on HEAD.