====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc4-next-20240418-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.4/1113 is trying to acquire lock: ffff88807d26dc68 (&pipe->mutex){+.+.}-{3:3}, at: iter_file_splice_write+0x335/0x14e0 fs/splice.c:687 but task is already holding lock: ffff88807ca24420 (sb_writers#4){.+.+}-{0:0}, at: do_splice+0xcf0/0x1900 fs/splice.c:1353 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (sb_writers#4){.+.+}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1654 [inline] sb_start_write+0x4d/0x1c0 include/linux/fs.h:1790 mnt_want_write+0x3f/0x90 fs/namespace.c:409 ovl_xattr_set+0x14e/0x520 fs/overlayfs/xattrs.c:63 ovl_own_xattr_set+0x173/0x1c0 fs/overlayfs/xattrs.c:213 __vfs_setxattr+0x468/0x4a0 fs/xattr.c:200 __vfs_setxattr_noperm+0x12e/0x660 fs/xattr.c:234 vfs_setxattr+0x221/0x430 fs/xattr.c:321 do_setxattr fs/xattr.c:629 [inline] setxattr+0x25d/0x2f0 fs/xattr.c:652 path_setxattr+0x1c0/0x2a0 fs/xattr.c:671 __do_sys_setxattr fs/xattr.c:687 [inline] __se_sys_setxattr fs/xattr.c:683 [inline] __x64_sys_setxattr+0xbb/0xd0 fs/xattr.c:683 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 down_read+0xb1/0xa40 kernel/locking/rwsem.c:1526 inode_lock_shared include/linux/fs.h:801 [inline] lookup_slow+0x45/0x70 fs/namei.c:1708 walk_component+0x2e1/0x410 fs/namei.c:2004 lookup_last fs/namei.c:2469 [inline] path_lookupat+0x16f/0x450 fs/namei.c:2493 filename_lookup+0x256/0x610 fs/namei.c:2522 kern_path+0x35/0x50 fs/namei.c:2630 lookup_bdev+0xc5/0x290 block/bdev.c:1128 resume_store+0x1a0/0x710 kernel/power/hibernate.c:1235 kernfs_fop_write_iter+0x3a1/0x500 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa72/0xc90 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&of->mutex){+.+.}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 iter_file_splice_write+0xbd7/0x14e0 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] do_splice+0xd77/0x1900 fs/splice.c:1354 __do_splice fs/splice.c:1436 [inline] __do_sys_splice fs/splice.c:1652 [inline] __se_sys_splice+0x331/0x4a0 fs/splice.c:1634 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&pipe->mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 iter_file_splice_write+0x335/0x14e0 fs/splice.c:687 do_splice_from fs/splice.c:941 [inline] do_splice+0xd77/0x1900 fs/splice.c:1354 __do_splice fs/splice.c:1436 [inline] __do_sys_splice fs/splice.c:1652 [inline] __se_sys_splice+0x331/0x4a0 fs/splice.c:1634 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: &pipe->mutex --> &ovl_i_mutex_dir_key[depth] --> sb_writers#4 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(sb_writers#4); lock(&ovl_i_mutex_dir_key[depth]); lock(sb_writers#4); lock(&pipe->mutex); *** DEADLOCK *** 1 lock held by syz-executor.4/1113: #0: ffff88807ca24420 (sb_writers#4){.+.+}-{0:0}, at: do_splice+0xcf0/0x1900 fs/splice.c:1353 stack backtrace: CPU: 0 PID: 1113 Comm: syz-executor.4 Not tainted 6.9.0-rc4-next-20240418-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 iter_file_splice_write+0x335/0x14e0 fs/splice.c:687 do_splice_from fs/splice.c:941 [inline] do_splice+0xd77/0x1900 fs/splice.c:1354 __do_splice fs/splice.c:1436 [inline] __do_sys_splice fs/splice.c:1652 [inline] __se_sys_splice+0x331/0x4a0 fs/splice.c:1634 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3ab807dea9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3ab8e110c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 00007f3ab81abf80 RCX: 00007f3ab807dea9 RDX: 000000000000000b RSI: 0000000000000000 RDI: 000000000000000a RBP: 00007f3ab80ca4a4 R08: 00000000ffffffe1 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f3ab81abf80 R15: 00007ffcfea07cc8