[syzbot] [hfs?] possible deadlock in hfs_find_init (2)

From: syzbot
Date: Mon Dec 26 2022 - 20:01:17 EST

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Hello,

syzbot found the following issue on:

HEAD commit: 51094a24b85e Merge tag 'hardening-v6.2-rc1-fixes' of git:/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15e0dc54480000
kernel config: https://syzkaller.appspot.com/x/.config?x=4e2d7bfa2d6d5a76
dashboard link: https://syzkaller.appspot.com/bug?extid=e390d66dda462b51fde1
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a26f3769fdfb/disk-51094a24.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5decc3ae71d7/vmlinux-51094a24.xz
kernel image: https://storage.googleapis.com/syzbot-assets/dd2ac18a5b04/bzImage-51094a24.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e390d66dda462b51fde1@xxxxxxxxxxxxxxxxxxxxxxxxx

======================================================
WARNING: possible circular locking dependency detected
6.1.0-syzkaller-14587-g51094a24b85e #0 Not tainted
------------------------------------------------------
syz-executor.5/14715 is trying to acquire lock:
ffff8880470440b0
(&tree->tree_lock
/1){+.+.}-{3:3}
, at: hfs_find_init+0x167/0x1e0

but task is already holding lock:
ffff88804170c1f8
(&HFS_I(tree->inode)->extents_lock
){+.+.}-{3:3}
, at: hfs_extend_file+0xde/0x1420 fs/hfs/extent.c:397

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1
(&HFS_I(tree->inode)->extents_lock
){+.+.}-{3:3}
:
lock_acquire+0x182/0x3c0 kernel/locking/lockdep.c:5668
__mutex_lock_common+0x1bd/0x26e0 kernel/locking/mutex.c:603
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799
hfs_extend_file+0xde/0x1420 fs/hfs/extent.c:397
hfs_bmap_reserve+0xfa/0x410 fs/hfs/btree.c:234
__hfs_ext_write_extent+0x1ea/0x460 fs/hfs/extent.c:121
__hfs_ext_cache_extent+0x67/0x980 fs/hfs/extent.c:174
hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
hfs_extend_file+0x323/0x1420 fs/hfs/extent.c:401
hfs_get_block+0x3fc/0xbb0 fs/hfs/extent.c:353
__block_write_begin_int+0x54c/0x1a80 fs/buffer.c:1991
__block_write_begin fs/buffer.c:2041 [inline]
block_write_begin+0x93/0x1e0 fs/buffer.c:2102
cont_write_begin+0x606/0x860 fs/buffer.c:2456
hfs_write_begin+0x86/0xd0 fs/hfs/inode.c:58
cont_expand_zero fs/buffer.c:2383 [inline]
cont_write_begin+0x2cf/0x860 fs/buffer.c:2446
hfs_write_begin+0x86/0xd0 fs/hfs/inode.c:58
generic_perform_write+0x2e4/0x5e0 mm/filemap.c:3772
__generic_file_write_iter+0x176/0x400 mm/filemap.c:3900
generic_file_write_iter+0xab/0x310 mm/filemap.c:3932
do_iter_write+0x6c2/0xc20 fs/read_write.c:861
vfs_writev fs/read_write.c:934 [inline]
do_pwritev+0x200/0x350 fs/read_write.c:1031
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (
&tree->tree_lock
/1){+.+.}-{3:3}
:
check_prev_add kernel/locking/lockdep.c:3097 [inline]
check_prevs_add kernel/locking/lockdep.c:3216 [inline]
validate_chain+0x1898/0x6ae0 kernel/locking/lockdep.c:3831
__lock_acquire+0x1292/0x1f60 kernel/locking/lockdep.c:5055
lock_acquire+0x182/0x3c0 kernel/locking/lockdep.c:5668
__mutex_lock_common+0x1bd/0x26e0 kernel/locking/mutex.c:603
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799
hfs_find_init+0x167/0x1e0
hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
hfs_extend_file+0x2f8/0x1420 fs/hfs/extent.c:401
hfs_bmap_reserve+0xfa/0x410 fs/hfs/btree.c:234
hfs_cat_create+0x1b5/0x8a0 fs/hfs/catalog.c:104
hfs_create+0x62/0xd0 fs/hfs/dir.c:202
lookup_open fs/namei.c:3413 [inline]
open_last_lookups fs/namei.c:3481 [inline]
path_openat+0x12ac/0x2dd0 fs/namei.c:3711
do_filp_open+0x264/0x4f0 fs/namei.c:3741
do_sys_openat2+0x124/0x4e0 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_open fs/open.c:1334 [inline]
__se_sys_open fs/open.c:1330 [inline]
__x64_sys_open+0x221/0x270 fs/open.c:1330
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&HFS_I(tree->inode)->extents_lock);
lock(&tree->tree_lock/1);
lock(&HFS_I(tree->inode)->extents_lock);
lock(&tree->tree_lock/1);

*** DEADLOCK ***

4 locks held by syz-executor.5/14715:
#0: ffff88802c73a460 (sb_writers#19){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:508
#1: ffff88804170bd28 (&type->i_mutex_dir_key#11){++++}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
#1: ffff88804170bd28 (&type->i_mutex_dir_key#11){++++}-{3:3}, at: open_last_lookups fs/namei.c:3478 [inline]
#1: ffff88804170bd28 (&type->i_mutex_dir_key#11){++++}-{3:3}, at: path_openat+0x7b9/0x2dd0 fs/namei.c:3711
#2: ffff88802a7440b0 (&tree->tree_lock){+.+.}-{3:3}, at: hfs_find_init+0x167/0x1e0
#3: ffff88804170c1f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xde/0x1420 fs/hfs/extent.c:397

stack backtrace:
CPU: 0 PID: 14715 Comm: syz-executor.5 Not tainted 6.1.0-syzkaller-14587-g51094a24b85e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1b1/0x290 lib/dump_stack.c:106
check_noncircular+0x2cc/0x390 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+0x1898/0x6ae0 kernel/locking/lockdep.c:3831
__lock_acquire+0x1292/0x1f60 kernel/locking/lockdep.c:5055
lock_acquire+0x182/0x3c0 kernel/locking/lockdep.c:5668
__mutex_lock_common+0x1bd/0x26e0 kernel/locking/mutex.c:603
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799
hfs_find_init+0x167/0x1e0
hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
hfs_extend_file+0x2f8/0x1420 fs/hfs/extent.c:401
hfs_bmap_reserve+0xfa/0x410 fs/hfs/btree.c:234
hfs_cat_create+0x1b5/0x8a0 fs/hfs/catalog.c:104
hfs_create+0x62/0xd0 fs/hfs/dir.c:202
lookup_open fs/namei.c:3413 [inline]
open_last_lookups fs/namei.c:3481 [inline]
path_openat+0x12ac/0x2dd0 fs/namei.c:3711
do_filp_open+0x264/0x4f0 fs/namei.c:3741
do_sys_openat2+0x124/0x4e0 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_open fs/open.c:1334 [inline]
__se_sys_open fs/open.c:1330 [inline]
__x64_sys_open+0x221/0x270 fs/open.c:1330
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fc71f08c0a9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc71fe9b168 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fc71f1ac050 RCX: 00007fc71f08c0a9
RDX: 0000000000000000 RSI: 000000000014d27e RDI: 0000000020000180
RBP: 00007fc71f0e7ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd5d3e729f R14: 00007fc71fe9b300 R15: 0000000000022000
</TASK>

---
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Next message: Michał Grzelak: "[net PATCH 1/2] dt-bindings: net: marvell,orion-mdio: Fix error"
Previous message: Yang, Weijiang: "Re: [PATCH 1/3] KVM: x86: Omit PMU MSRs from KVM_GET_MSR_INDEX_LIST if !enable_pmu"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]