From: syzbot <syzbot+a84e36883956fb0221b4@syzkaller.appspotmail.com>
To: adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org,
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com,
tytso@mit.edu
Subject: [syzbot] possible deadlock in ext4_ind_migrate
Date: Sun, 18 Dec 2022 07:03:34 -0800 [thread overview]
Message-ID: <000000000000b1b8bf05f01b81d7@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: a5541c0811a0 Merge branch 'for-next/core' into for-kernelci
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=12802800480000
kernel config: https://syzkaller.appspot.com/x/.config?x=cbd4e584773e9397
dashboard link: https://syzkaller.appspot.com/bug?extid=a84e36883956fb0221b4
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4b7702208fb9/disk-a5541c08.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9ec0153ec051/vmlinux-a5541c08.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6f8725ad290a/Image-a5541c08.gz.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a84e36883956fb0221b4@syzkaller.appspotmail.com
======================================================
WARNING: possible circular locking dependency detected
6.1.0-rc8-syzkaller-33330-ga5541c0811a0 #0 Not tainted
------------------------------------------------------
syz-executor.3/8019 is trying to acquire lock:
ffff000118015b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ind_migrate+0xc8/0x318 fs/ext4/migrate.c:624
but task is already holding lock:
ffff000113706d30 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
ffff000113706d30 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_fileattr_set+0x78/0x458 fs/ioctl.c:681
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&sb->s_type->i_mutex_key#8){++++}-{3:3}:
down_read+0x5c/0x78 kernel/locking/rwsem.c:1509
inode_lock_shared include/linux/fs.h:766 [inline]
ext4_bmap+0x34/0x1c8 fs/ext4/inode.c:3164
bmap+0x40/0x6c fs/inode.c:1798
jbd2_journal_bmap fs/jbd2/journal.c:977 [inline]
__jbd2_journal_erase fs/jbd2/journal.c:1789 [inline]
jbd2_journal_flush+0x2a8/0x55c fs/jbd2/journal.c:2492
ext4_ioctl_checkpoint fs/ext4/ioctl.c:1081 [inline]
__ext4_ioctl fs/ext4/ioctl.c:1586 [inline]
ext4_ioctl+0x1cb8/0x2378 fs/ext4/ioctl.c:1606
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl fs/ioctl.c:856 [inline]
__arm64_sys_ioctl+0xd0/0x140 fs/ioctl.c:856
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x48/0x140 arch/arm64/kernel/syscall.c:197
el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584
-> #1 (&journal->j_checkpoint_mutex){+.+.}-{3:3}:
__mutex_lock_common+0xd4/0xca8 kernel/locking/mutex.c:603
mutex_lock_io_nested+0x6c/0x88 kernel/locking/mutex.c:833
__jbd2_log_wait_for_space+0xc0/0x330 fs/jbd2/checkpoint.c:110
add_transaction_credits+0x4b4/0x604 fs/jbd2/transaction.c:298
start_this_handle+0x2a0/0x7fc fs/jbd2/transaction.c:422
jbd2__journal_start+0x148/0x1f0 fs/jbd2/transaction.c:520
__ext4_journal_start_sb+0x124/0x1dc fs/ext4/ext4_jbd2.c:105
__ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline]
ext4_ind_migrate+0xec/0x318 fs/ext4/migrate.c:626
ext4_ioctl_setflags+0x5c0/0x5f0 fs/ext4/ioctl.c:695
ext4_fileattr_set+0x174/0x528 fs/ext4/ioctl.c:1003
vfs_fileattr_set+0x400/0x458 fs/ioctl.c:696
do_vfs_ioctl+0x1374/0x16a4
__do_sys_ioctl fs/ioctl.c:868 [inline]
__se_sys_ioctl fs/ioctl.c:856 [inline]
__arm64_sys_ioctl+0x98/0x140 fs/ioctl.c:856
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x48/0x140 arch/arm64/kernel/syscall.c:197
el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584
-> #0 (&sbi->s_writepages_rwsem){++++}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3097 [inline]
check_prevs_add kernel/locking/lockdep.c:3216 [inline]
validate_chain kernel/locking/lockdep.c:3831 [inline]
__lock_acquire+0x1530/0x3084 kernel/locking/lockdep.c:5055
lock_acquire+0x100/0x1f8 kernel/locking/lockdep.c:5668
percpu_down_write+0x6c/0x188 kernel/locking/percpu-rwsem.c:227
ext4_ind_migrate+0xc8/0x318 fs/ext4/migrate.c:624
ext4_ioctl_setflags+0x5c0/0x5f0 fs/ext4/ioctl.c:695
ext4_fileattr_set+0x174/0x528 fs/ext4/ioctl.c:1003
vfs_fileattr_set+0x400/0x458 fs/ioctl.c:696
do_vfs_ioctl+0x1374/0x16a4
__do_sys_ioctl fs/ioctl.c:868 [inline]
__se_sys_ioctl fs/ioctl.c:856 [inline]
__arm64_sys_ioctl+0x98/0x140 fs/ioctl.c:856
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x48/0x140 arch/arm64/kernel/syscall.c:197
el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584
other info that might help us debug this:
Chain exists of:
&sbi->s_writepages_rwsem --> &journal->j_checkpoint_mutex --> &sb->s_type->i_mutex_key#8
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sb->s_type->i_mutex_key#8);
lock(&journal->j_checkpoint_mutex);
lock(&sb->s_type->i_mutex_key#8);
lock(&sbi->s_writepages_rwsem);
*** DEADLOCK ***
2 locks held by syz-executor.3/8019:
#0: ffff000118016460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write_file+0x28/0xd8 fs/namespace.c:437
#1: ffff000113706d30 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
#1: ffff000113706d30 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_fileattr_set+0x78/0x458 fs/ioctl.c:681
stack backtrace:
CPU: 1 PID: 8019 Comm: syz-executor.3 Not tainted 6.1.0-rc8-syzkaller-33330-ga5541c0811a0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call trace:
dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:156
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:163
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x104/0x16c lib/dump_stack.c:106
dump_stack+0x1c/0x58 lib/dump_stack.c:113
print_circular_bug+0x2c4/0x2c8 kernel/locking/lockdep.c:2055
check_noncircular+0x14c/0x154 kernel/locking/lockdep.c:2177
check_prev_add kernel/locking/lockdep.c:3097 [inline]
check_prevs_add kernel/locking/lockdep.c:3216 [inline]
validate_chain kernel/locking/lockdep.c:3831 [inline]
__lock_acquire+0x1530/0x3084 kernel/locking/lockdep.c:5055
lock_acquire+0x100/0x1f8 kernel/locking/lockdep.c:5668
percpu_down_write+0x6c/0x188 kernel/locking/percpu-rwsem.c:227
ext4_ind_migrate+0xc8/0x318 fs/ext4/migrate.c:624
ext4_ioctl_setflags+0x5c0/0x5f0 fs/ext4/ioctl.c:695
ext4_fileattr_set+0x174/0x528 fs/ext4/ioctl.c:1003
vfs_fileattr_set+0x400/0x458 fs/ioctl.c:696
do_vfs_ioctl+0x1374/0x16a4
__do_sys_ioctl fs/ioctl.c:868 [inline]
__se_sys_ioctl fs/ioctl.c:856 [inline]
__arm64_sys_ioctl+0x98/0x140 fs/ioctl.c:856
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x48/0x140 arch/arm64/kernel/syscall.c:197
el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
reply other threads:[~2022-12-18 15:03 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=000000000000b1b8bf05f01b81d7@google.com \
--to=syzbot+a84e36883956fb0221b4@syzkaller.appspotmail.com \
--cc=adilger.kernel@dilger.ca \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=syzkaller-bugs@googlegroups.com \
--cc=tytso@mit.edu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.