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KCSAN: data-race in fsnotify_detach_mark / fsnotify_handle_inode_event (2)

Status: moderation: reported on 2024/07/06 23:50
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+876352de1b1faa223a9f@syzkaller.appspotmail.com
First crash: 6d11h, last: 2d19h
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in fsnotify_detach_mark / fsnotify_handle_inode_event fs 226 83d 218d 0/27 auto-obsoleted due to no activity on 2024/05/18 20:42

Sample crash report:
EXT4-fs (loop2): couldn't read superblock of external journal
==================================================================
BUG: KCSAN: data-race in fsnotify_detach_mark / fsnotify_handle_inode_event

write to 0xffff8881241aadb4 of 4 bytes by task 8001 on cpu 1:
 fsnotify_detach_mark+0xe1/0x190 fs/notify/mark.c:511
 fsnotify_destroy_mark+0x9a/0x1a0 fs/notify/mark.c:553
 __do_sys_inotify_rm_watch fs/notify/inotify/inotify_user.c:816 [inline]
 __se_sys_inotify_rm_watch+0xfd/0x180 fs/notify/inotify/inotify_user.c:793
 __x64_sys_inotify_rm_watch+0x31/0x40 fs/notify/inotify/inotify_user.c:793
 x64_sys_call+0x1b06/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:256
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881241aadb4 of 4 bytes by task 10058 on cpu 0:
 fsnotify_handle_inode_event+0xf6/0x1f0 fs/notify/fsnotify.c:276
 fsnotify_handle_event fs/notify/fsnotify.c:336 [inline]
 send_to_group fs/notify/fsnotify.c:384 [inline]
 fsnotify+0x10ba/0x11a0 fs/notify/fsnotify.c:593
 __fsnotify_parent+0x285/0x370 fs/notify/fsnotify.c:250
 fsnotify_parent include/linux/fsnotify.h:96 [inline]
 fsnotify_file include/linux/fsnotify.h:131 [inline]
 fsnotify_close include/linux/fsnotify.h:412 [inline]
 __fput+0x5ca/0x6f0 fs/file_table.c:408
 __fput_sync+0x44/0x60 fs/file_table.c:507
 __do_sys_close fs/open.c:1563 [inline]
 __se_sys_close+0x101/0x1b0 fs/open.c:1548
 __x64_sys_close+0x1f/0x30 fs/open.c:1548
 x64_sys_call+0x25f1/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:4
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000003 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10058 Comm: syz.2.2006 Not tainted 6.10.0-rc7-syzkaller-00012-g34afb82a3c67 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
==================================================================
loop2: detected capacity change from 0 to 512
EXT4-fs (loop2): external journal device major/minor numbers have changed
EXT4-fs (loop2): couldn't read superblock of external journal
loop2: detected capacity change from 0 to 512
EXT4-fs (loop2): external journal device major/minor numbers have changed
EXT4-fs (loop2): couldn't read superblock of external journal
loop2: detected capacity change from 0 to 512
EXT4-fs (loop2): external journal device major/minor numbers have changed
EXT4-fs (loop2): couldn't read superblock of external journal

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/10 15:49 upstream 34afb82a3c67 bc144f9a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / fsnotify_handle_inode_event
2024/07/06 23:49 upstream 22f902dfc51e 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / fsnotify_handle_inode_event
* Struck through repros no longer work on HEAD.