syzbot


possible deadlock in hfs_extend_file (3)

Status: upstream: reported on 2024/03/13 05:11
Reported-by: syzbot+033048aa2a56eacb2789@syzkaller.appspotmail.com
First crash: 554d, last: 8d18h
Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 possible deadlock in hfs_extend_file hfs 4 1 996d 996d 0/1 upstream: reported on 2022/12/27 15:22
linux-5.15 possible deadlock in hfs_extend_file (2) 4 1 696d 696d 0/3 auto-obsoleted due to no activity on 2024/01/31 18:25
linux-6.1 possible deadlock in hfs_extend_file 4 7 734d 920d 0/3 auto-obsoleted due to no activity on 2023/12/24 21:20
upstream possible deadlock in hfs_extend_file hfs 4 46 757d 1001d 0/29 auto-obsoleted due to no activity on 2023/11/06 09:48
linux-6.1 possible deadlock in hfs_extend_file (2) origin:upstream 4 C 130 10d 532d 0/3 upstream: reported C repro on 2024/04/04 03:11
upstream possible deadlock in hfs_extend_file (3) hfs 4 C unreliable 2584 4h48m 518d 0/29 upstream: reported C repro on 2024/04/18 14:41
linux-6.6 possible deadlock in hfs_extend_file origin:upstream missing-backport 4 C 28 6d09h 93d 0/2 upstream: reported C repro on 2025/06/17 13:12
upstream possible deadlock in hfs_extend_file (2) hfs 4 C done done 4 625d 646d 0/29 auto-obsoleted due to no activity on 2024/04/11 05:11
linux-5.15 possible deadlock in hfs_extend_file 4 5 821d 885d 0/3 auto-obsoleted due to no activity on 2023/09/28 05:53

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.2.722/7167 is trying to acquire lock:
ffff88802203a178 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xd7/0x1280 fs/hfs/extent.c:397

but task is already holding lock:
ffff88807ebd20b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&tree->tree_lock/1){+.+.}-{3:3}:
       __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1
       hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
       hfs_extend_file+0x2eb/0x1280 fs/hfs/extent.c:401
       hfs_bmap_reserve+0x103/0x420 fs/hfs/btree.c:231
       hfs_cat_create+0x1c0/0x8d0 fs/hfs/catalog.c:104
       hfs_mkdir+0x68/0xe0 fs/hfs/dir.c:232
       vfs_mkdir+0x387/0x570 fs/namei.c:4065
       do_mkdirat+0x1d7/0x5a0 fs/namei.c:4090
       __do_sys_mkdirat fs/namei.c:4105 [inline]
       __se_sys_mkdirat fs/namei.c:4103 [inline]
       __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4103
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #0 (&HFS_I(tree->inode)->extents_lock){+.+.}-{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:3788 [inline]
       __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
       lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
       __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       hfs_extend_file+0xd7/0x1280 fs/hfs/extent.c:397
       hfs_bmap_reserve+0x103/0x420 fs/hfs/btree.c:231
       __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121
       hfs_ext_write_extent+0x15e/0x1e0 fs/hfs/extent.c:144
       hfs_write_inode+0x8e/0x970 fs/hfs/inode.c:432
       write_inode fs/fs-writeback.c:1495 [inline]
       __writeback_single_inode+0x6c3/0xda0 fs/fs-writeback.c:1705
       writeback_single_inode+0x221/0x8b0 fs/fs-writeback.c:1760
       write_inode_now+0x217/0x280 fs/fs-writeback.c:2801
       hfs_file_fsync+0xa3/0x140 fs/hfs/inode.c:680
       generic_write_sync include/linux/fs.h:2989 [inline]
       generic_file_write_iter+0x157/0x1b0 mm/filemap.c:3948
       call_write_iter include/linux/fs.h:2172 [inline]
       new_sync_write fs/read_write.c:507 [inline]
       vfs_write+0x712/0xd00 fs/read_write.c:594
       ksys_write+0x14d/0x250 fs/read_write.c:647
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

other info that might help us debug this:

 Possible unsafe locking scenario:

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

 *** DEADLOCK ***

4 locks held by syz.2.722/7167:
 #0: ffff888059013270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2bf/0x370 fs/file.c:1056
 #1: ffff888077910460 (sb_writers#15){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590
 #2: ffff88805d5abd28 (&sb->s_type->i_mutex_key#23){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #2: ffff88805d5abd28 (&sb->s_type->i_mutex_key#23){+.+.}-{3:3}, at: hfs_file_fsync+0x99/0x140 fs/hfs/inode.c:677
 #3: ffff88807ebd20b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1

stack backtrace:
CPU: 0 PID: 7167 Comm: syz.2.722 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 check_noncircular+0x274/0x310 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:3788 [inline]
 __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 hfs_extend_file+0xd7/0x1280 fs/hfs/extent.c:397
 hfs_bmap_reserve+0x103/0x420 fs/hfs/btree.c:231
 __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121
 hfs_ext_write_extent+0x15e/0x1e0 fs/hfs/extent.c:144
 hfs_write_inode+0x8e/0x970 fs/hfs/inode.c:432
 write_inode fs/fs-writeback.c:1495 [inline]
 __writeback_single_inode+0x6c3/0xda0 fs/fs-writeback.c:1705
 writeback_single_inode+0x221/0x8b0 fs/fs-writeback.c:1760
 write_inode_now+0x217/0x280 fs/fs-writeback.c:2801
 hfs_file_fsync+0xa3/0x140 fs/hfs/inode.c:680
 generic_write_sync include/linux/fs.h:2989 [inline]
 generic_file_write_iter+0x157/0x1b0 mm/filemap.c:3948
 call_write_iter include/linux/fs.h:2172 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x712/0xd00 fs/read_write.c:594
 ksys_write+0x14d/0x250 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f76ed6d1ba9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f76eb918038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f76ed919090 RCX: 00007f76ed6d1ba9
RDX: 0000000000000c34 RSI: 0000200000000940 RDI: 000000000000000b
RBP: 00007f76ed754e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f76ed919128 R14: 00007f76ed919090 R15: 00007ffc78c468e8
 </TASK>

Crashes (161):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/10 08:00 linux-5.15.y de9476bb4f1b fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/09/10 08:00 linux-5.15.y de9476bb4f1b fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/09/09 16:21 linux-5.15.y 7a6c2d093c45 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/08/31 12:50 linux-5.15.y 01879f56bdde 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/08/27 17:10 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/08/22 10:00 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/08/08 14:57 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/07/28 22:14 linux-5.15.y c79648372d02 6654ea9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/07/27 09:00 linux-5.15.y c79648372d02 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/07/20 17:34 linux-5.15.y c79648372d02 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/07/16 20:30 linux-5.15.y 89950c454265 44f8051e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/06/14 16:58 linux-5.15.y 1c700860e8bc 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/06/03 21:57 linux-5.15.y 98f47d0e9b8c a30356b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/05/29 08:38 linux-5.15.y 98f47d0e9b8c 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/05/25 19:21 linux-5.15.y 98f47d0e9b8c 2d4582d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/05/22 01:41 linux-5.15.y a68c15152131 0919b50b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/05/20 12:24 linux-5.15.y a68c15152131 b47f9e02 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/05/18 07:47 linux-5.15.y a68c15152131 f41472b0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/05/17 21:29 linux-5.15.y 3b8db0e4f263 f41472b0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/05/13 19:47 linux-5.15.y 3b8db0e4f263 7344edeb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/05/12 02:38 linux-5.15.y 3b8db0e4f263 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/05/09 09:17 linux-5.15.y 3b8db0e4f263 bb813bcc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/04/17 16:24 linux-5.15.y f7347f400572 229db4cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/04/03 18:35 linux-5.15.y 0c935c049b5c d7ae3a11 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/04/03 14:55 linux-5.15.y 0c935c049b5c 996a9618 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2024/03/13 05:10 linux-5.15.y 574362648507 db5b7ff0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in hfs_extend_file
2025/08/05 10:16 linux-5.15.y c79648372d02 37880f40 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/07/22 19:54 linux-5.15.y c79648372d02 8e9d1dc1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/07/19 00:55 linux-5.15.y c79648372d02 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/06/18 14:25 linux-5.15.y 1c700860e8bc ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/06/18 00:25 linux-5.15.y 1c700860e8bc e77fae15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/05/30 22:36 linux-5.15.y 98f47d0e9b8c 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/05/19 16:08 linux-5.15.y a68c15152131 b84f0537 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/05/16 05:11 linux-5.15.y 3b8db0e4f263 cfde8269 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/05/12 06:57 linux-5.15.y 3b8db0e4f263 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/05/10 18:33 linux-5.15.y 3b8db0e4f263 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/05/01 02:08 linux-5.15.y f7347f400572 ce7952f4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/04/27 11:55 linux-5.15.y f7347f400572 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/04/11 17:47 linux-5.15.y f7347f400572 94486846 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/04/11 05:34 linux-5.15.y f7347f400572 94486846 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/04/10 17:14 linux-5.15.y f7347f400572 1ef3ab4d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/04/09 10:49 linux-5.15.y 0c935c049b5c 47d015b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/03/30 10:30 linux-5.15.y 0c935c049b5c d3999433 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
2025/02/17 00:24 linux-5.15.y c16c81c81336 40a34ec9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in hfs_extend_file
* Struck through repros no longer work on HEAD.