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possible deadlock in hfs_find_init

Status: upstream: reported on 2023/03/22 23:14
Reported-by: syzbot+5ec6d29e9352c6f10dc7@syzkaller.appspotmail.com
First crash: 69d, last: 32d
▶ ▼ Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 possible deadlock in hfs_find_init hfs C 1 92d 124d 0/1 upstream: reported C repro on 2023/01/26 19:14
linux-4.19 possible deadlock in hfs_find_init hfs C error 7 86d 152d 0/1 upstream: reported C repro on 2022/12/30 06:08
upstream possible deadlock in hfs_find_init (2) hfs C error 52 5d10h 155d 0/24 upstream: reported C repro on 2022/12/27 00:59
linux-6.1 possible deadlock in hfs_find_init 8 3d15h 71d 0/3 upstream: reported on 2023/03/20 17:38
upstream possible deadlock in hfs_find_init hfs C done error 1 874d 1864d 22/24 fixed on 2021/11/10 00:50

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
5.15.109-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.2/10017 is trying to acquire lock:
ffff0000d81980b0 (&tree->tree_lock#2/1){+.+.}-{3:3}, at: hfs_find_init+0x148/0x1c8

but task is already holding lock:
ffff0000d132c1f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xe4/0x10e4 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}:
       __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
       hfs_extend_file+0xe4/0x10e4 fs/hfs/extent.c:397
       hfs_bmap_reserve+0xd0/0x3b4 fs/hfs/btree.c:231
       __hfs_ext_write_extent+0x1a0/0x468 fs/hfs/extent.c:121
       __hfs_ext_cache_extent+0x84/0x754 fs/hfs/extent.c:174
       hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
       hfs_extend_file+0x278/0x10e4 fs/hfs/extent.c:401
       hfs_get_block+0x3ac/0x9fc fs/hfs/extent.c:353
       __block_write_begin_int+0x3ec/0x1608 fs/buffer.c:2012
       __block_write_begin fs/buffer.c:2062 [inline]
       block_write_begin fs/buffer.c:2122 [inline]
       cont_write_begin+0x538/0x710 fs/buffer.c:2471
       hfs_write_begin+0xa8/0xf8 fs/hfs/inode.c:59
       generic_perform_write+0x24c/0x520 mm/filemap.c:3776
       __generic_file_write_iter+0x230/0x454 mm/filemap.c:3903
       generic_file_write_iter+0xb4/0x1b8 mm/filemap.c:3935
       call_write_iter include/linux/fs.h:2103 [inline]
       new_sync_write fs/read_write.c:507 [inline]
       vfs_write+0x87c/0xb3c fs/read_write.c:594
       ksys_write+0x15c/0x26c fs/read_write.c:647
       __do_sys_write fs/read_write.c:659 [inline]
       __se_sys_write fs/read_write.c:656 [inline]
       __arm64_sys_write+0x7c/0x90 fs/read_write.c:656
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:596
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #0 (&tree->tree_lock#2/1){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain kernel/locking/lockdep.c:3787 [inline]
       __lock_acquire+0x32cc/0x7620 kernel/locking/lockdep.c:5011
       lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5622
       __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
       hfs_find_init+0x148/0x1c8
       hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
       hfs_extend_file+0x24c/0x10e4 fs/hfs/extent.c:401
       hfs_bmap_reserve+0xd0/0x3b4 fs/hfs/btree.c:231
       hfs_cat_move+0x194/0xcb4 fs/hfs/catalog.c:310
       hfs_rename+0x1e4/0x2b4 fs/hfs/dir.c:299
       vfs_rename+0x9e0/0xe80 fs/namei.c:4736
       do_renameat2+0x980/0x1040 fs/namei.c:4887
       __do_sys_renameat2 fs/namei.c:4920 [inline]
       __se_sys_renameat2 fs/namei.c:4917 [inline]
       __arm64_sys_renameat2+0xe0/0xfc fs/namei.c:4917
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:596
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

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#2/1);
                               lock(&HFS_I(tree->inode)->extents_lock);
  lock(&tree->tree_lock#2/1);

 *** DEADLOCK ***

4 locks held by syz-executor.2/10017:
 #0: ffff00012b16a460 (sb_writers#19){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:377
 #1: ffff0000d132f128 (&type->i_mutex_dir_key#10/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline]
 #1: ffff0000d132f128 (&type->i_mutex_dir_key#10/1){+.+.}-{3:3}, at: lock_rename+0xf0/0x18c fs/namei.c:2967
 #2: ffff00011c9960b0 (&tree->tree_lock#2){+.+.}-{3:3}, at: hfs_find_init+0x148/0x1c8
 #3: ffff0000d132c1f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xe4/0x10e4 fs/hfs/extent.c:397

stack backtrace:
CPU: 1 PID: 10017 Comm: syz-executor.2 Not tainted 5.15.109-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2011
 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain kernel/locking/lockdep.c:3787 [inline]
 __lock_acquire+0x32cc/0x7620 kernel/locking/lockdep.c:5011
 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5622
 __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
 hfs_find_init+0x148/0x1c8
 hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
 hfs_extend_file+0x24c/0x10e4 fs/hfs/extent.c:401
 hfs_bmap_reserve+0xd0/0x3b4 fs/hfs/btree.c:231
 hfs_cat_move+0x194/0xcb4 fs/hfs/catalog.c:310
 hfs_rename+0x1e4/0x2b4 fs/hfs/dir.c:299
 vfs_rename+0x9e0/0xe80 fs/namei.c:4736
 do_renameat2+0x980/0x1040 fs/namei.c:4887
 __do_sys_renameat2 fs/namei.c:4920 [inline]
 __se_sys_renameat2 fs/namei.c:4917 [inline]
 __arm64_sys_renameat2+0xe0/0xfc fs/namei.c:4917
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:596
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
hfs: request for non-existent node 16777216 in B*Tree
hfs: request for non-existent node 16777216 in B*Tree

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Manager Title
2023/04/28 19:58 linux-5.15.y f48aeeaaa64c 62df2017 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2023/04/19 22:01 linux-5.15.y 4fdad925aa1a a219f34e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
2023/03/22 23:13 linux-5.15.y 115472395b0a f94b4a29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_find_init
* Struck through repros no longer work on HEAD.