syzbot


KCSAN: data-race in jbd2_journal_unlock_updates / start_this_handle

Status: auto-closed as invalid on 2021/12/26 01:56
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 402d, last: 380d

Sample crash report:
==================================================================
BUG: KCSAN: data-race in jbd2_journal_unlock_updates / start_this_handle

write to 0xffff888103045854 of 4 bytes by task 28499 on cpu 1:
 jbd2_journal_unlock_updates+0x59/0x90 fs/jbd2/transaction.c:912
 ext4_ioctl_group_add+0x187/0x300 fs/ext4/ioctl.c:710
 __ext4_ioctl fs/ext4/ioctl.c:1007 [inline]
 ext4_ioctl+0xa88/0x2170 fs/ext4/ioctl.c:1279
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888103045854 of 4 bytes by task 28504 on cpu 0:
 start_this_handle+0x334/0x1050 fs/jbd2/transaction.c:404
 jbd2__journal_start+0x1fc/0x3f0 fs/jbd2/transaction.c:525
 __ext4_journal_start_sb+0x159/0x310 fs/ext4/ext4_jbd2.c:105
 __ext4_new_inode+0xd95/0x2fc0 fs/ext4/ialloc.c:1080
 ext4_symlink+0x2cc/0x700 fs/ext4/namei.c:3293
 vfs_symlink+0x241/0x330 fs/namei.c:4248
 do_symlinkat+0x104/0x380 fs/namei.c:4277
 __do_sys_symlink fs/namei.c:4299 [inline]
 __se_sys_symlink fs/namei.c:4297 [inline]
 __x64_sys_symlink+0x52/0x60 fs/namei.c:4297
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 28504 Comm: syz-executor.5 Not tainted 5.16.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (3):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/11/21 01:48 upstream 61564e7b3abc 4eb20a4e .config log report info KCSAN: data-race in jbd2_journal_unlock_updates / start_this_handle
ci2-upstream-kcsan-gce 2021/10/31 07:45 upstream 119c85055d86 098b5d53 .config log report info KCSAN: data-race in jbd2_journal_unlock_updates / start_this_handle
ci2-upstream-kcsan-gce 2021/10/30 07:56 upstream a379fbbcb88b 098b5d53 .config log report info KCSAN: data-race in jbd2_journal_unlock_updates / start_this_handle
* Struck through repros no longer work on HEAD.