KCSAN: data-race in __ext4_update_other_inode_time / __ext4_update_other_inode

KCSAN: data-race in __ext4_update_other_inode_time / __ext4_update_other_inode_time
Status: auto-closed as invalid on 2021/01/22 10:57
Reported-by: syzbot+9adc47c3254935447e45@syzkaller.appspotmail.com
First crash: 103d, last: 40d

Sample crash report:

==================================================================
BUG: KCSAN: data-race in __ext4_update_other_inode_time / __ext4_update_other_inode_time

write to 0xffff888015003c18 of 8 bytes by task 8489 on cpu 1:
 __ext4_update_other_inode_time+0xc1/0x550 fs/ext4/inode.c:4966
 ext4_update_other_inodes_time fs/ext4/inode.c:5002 [inline]
 ext4_do_update_inode fs/ext4/inode.c:5131 [inline]
 ext4_mark_iloc_dirty+0x1286/0x1650 fs/ext4/inode.c:5712
 __ext4_mark_inode_dirty+0x450/0x610 fs/ext4/inode.c:5906
 ext4_rmdir+0x8a9/0x930 fs/ext4/namei.c:3168
 vfs_rmdir+0x135/0x290 fs/namei.c:3713
 do_rmdir+0x16e/0x300 fs/namei.c:3774
 __do_sys_rmdir fs/namei.c:3792 [inline]
 __se_sys_rmdir fs/namei.c:3790 [inline]
 __x64_sys_rmdir+0x2c/0x30 fs/namei.c:3790
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888015003c18 of 8 bytes by task 5930 on cpu 0:
 __ext4_update_other_inode_time+0x45/0x550 fs/ext4/inode.c:4955
 ext4_update_other_inodes_time fs/ext4/inode.c:5002 [inline]
 ext4_do_update_inode fs/ext4/inode.c:5131 [inline]
 ext4_mark_iloc_dirty+0x1286/0x1650 fs/ext4/inode.c:5712
 __ext4_mark_inode_dirty+0x450/0x610 fs/ext4/inode.c:5906
 ext4_da_write_end+0x4c7/0x760 fs/ext4/inode.c:3092
 generic_perform_write+0x23e/0x3a0 mm/filemap.c:3416
 ext4_buffered_write_iter+0x2e5/0x3d0 fs/ext4/file.c:270
 ext4_file_write_iter+0x45e/0x1090 fs/ext4/file.c:503
 call_write_iter include/linux/fs.h:1901 [inline]
 new_sync_write fs/read_write.c:518 [inline]
 vfs_write+0x6d4/0x7c0 fs/read_write.c:605
 ksys_write+0xce/0x180 fs/read_write.c:658
 __do_sys_write fs/read_write.c:670 [inline]
 __se_sys_write fs/read_write.c:667 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:667
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5930 Comm: rs:main Q:Reg Not tainted 5.10.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (4):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Maintainers
ci2-upstream-kcsan-gce	2020/12/18 10:57	upstream	d64c6f96	04201c06	.config	log	report	info	adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, tytso@mit.edu
ci2-upstream-kcsan-gce	2020/11/20 00:51	upstream	131ad0b6	0767f13f	.config	log	report	info	adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, tytso@mit.edu
ci2-upstream-kcsan-gce	2020/11/07 06:53	upstream	bf3e7628	cba33199	.config	log	report	info	adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, tytso@mit.edu
ci2-upstream-kcsan-gce	2020/10/16 01:45	upstream	726eb70e	6e262c73	.config	log	report	info	adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, tytso@mit.edu