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KCSAN: data-race in dentry_lru_isolate / step_into (4)

Status: auto-obsoleted due to no activity on 2023/04/06 15:13
Subsystems: fs
[Documentation on labels]
First crash: 526d, last: 441d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in dentry_lru_isolate / step_into fs 1 725d 725d 0/26 auto-closed as invalid on 2022/06/16 15:50
upstream KCSAN: data-race in dentry_lru_isolate / step_into (2) fs 1 665d 665d 0/26 auto-closed as invalid on 2022/08/15 07:08
upstream KCSAN: data-race in dentry_lru_isolate / step_into (5) kernfs 1 337d 337d 0/26 auto-obsoleted due to no activity on 2023/07/09 13:37
upstream KCSAN: data-race in dentry_lru_isolate / step_into (3) fs 1 566d 566d 0/26 auto-obsoleted due to no activity on 2022/11/22 05:54

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

write to 0xffff88810b322600 of 4 bytes by task 3144 on cpu 1:
 d_lru_shrink_move fs/dcache.c:480 [inline]
 dentry_lru_isolate+0x143/0x210 fs/dcache.c:1257
 __list_lru_walk_one+0x180/0x3b0 mm/list_lru.c:231
 list_lru_walk_one+0x80/0xa0 mm/list_lru.c:276
 list_lru_shrink_walk include/linux/list_lru.h:194 [inline]
 prune_dcache_sb+0x76/0xb0 fs/dcache.c:1280
 super_cache_scan+0x26c/0x310 fs/super.c:104
 do_shrink_slab+0x2a0/0x640 mm/vmscan.c:847
 shrink_slab_memcg mm/vmscan.c:916 [inline]
 shrink_slab+0x2bc/0x520 mm/vmscan.c:995
 shrink_node_memcgs mm/vmscan.c:6147 [inline]
 shrink_node+0xaf5/0x14f0 mm/vmscan.c:6176
 shrink_zones mm/vmscan.c:6414 [inline]
 do_try_to_free_pages+0x40d/0xc80 mm/vmscan.c:6476
 try_to_free_mem_cgroup_pages+0x1e2/0x480 mm/vmscan.c:6791
 reclaim_high+0xca/0x110 mm/memcontrol.c:2393
 mem_cgroup_handle_over_high+0x8c/0x1a0 mm/memcontrol.c:2578
 resume_user_mode_work include/linux/resume_user_mode.h:58 [inline]
 exit_to_user_mode_loop+0x99/0xe0 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0x6a/0xa0 kernel/entry/common.c:203
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:296
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88810b322600 of 4 bytes by task 20971 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:1836
 walk_component+0x164/0x230 fs/namei.c:1999
 lookup_last fs/namei.c:2450 [inline]
 path_lookupat+0x10a/0x2a0 fs/namei.c:2474
 filename_lookup+0x126/0x300 fs/namei.c:2503
 user_path_at_empty+0x42/0x110 fs/namei.c:2876
 user_path_at include/linux/namei.h:57 [inline]
 __do_sys_chdir fs/open.c:514 [inline]
 __se_sys_chdir+0x4f/0x140 fs/open.c:508
 __x64_sys_chdir+0x1f/0x30 fs/open.c:508
 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: 0x00280000 -> 0x00008000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 20971 Comm: syz-executor.3 Not tainted 6.2.0-rc8-syzkaller-00151-g925cf0457d7e-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/02/19 20:26 upstream 925cf0457d7e bcdf85f8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dentry_lru_isolate / step_into
2023/02/08 16:21 upstream 0983f6bf2bfc fc9c934e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dentry_lru_isolate / step_into
2023/01/03 23:07 upstream 69b41ac87e4a f0036e18 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dentry_lru_isolate / step_into
2022/12/09 11:16 upstream f3e8416619ce 1034e5fa .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dentry_lru_isolate / step_into
2022/11/27 01:08 upstream 644e9524388a f4470a7b .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in dentry_lru_isolate / step_into
* Struck through repros no longer work on HEAD.