min: POS_MIN max: SPOS_MAX, btree topology error: bcachefs (loop0): flagging btree snapshots lost data bcachefs (loop0): error reading btree root btree=snapshots level=0: btree_node_read_error, fixing bcachefs (loop0): scan_for_btree_nodes... bcachefs (loop0): btree node scan found 2 nodes after overwrites done bcachefs (loop0): check_topology... bcachefs (loop0): btree root extents unreadable, must recover from scan bcachefs (loop0): no nodes found for btree extents, continuing bcachefs (loop0): btree root snapshots unreadable, must recover from scan bcachefs (loop0): no nodes found for btree snapshots, continuing done bcachefs (loop0): accounting_read... done bcachefs (loop0): alloc_read... done bcachefs (loop0): snapshots_read... bcachefs (loop0): running explicit recovery pass reconstruct_snapshots (21), currently at snapshots_read (7) done bcachefs (loop0): check_allocations... bcachefs (loop0): btree ptr not marked in member info btree allocated bitmap u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 7589ab5e0c11cc7a written 24 min_key POS_MIN durability: 1 ptr: 0:38:0 gen 0, fixing bcachefs (loop0): btree ptr not marked in member info btree allocated bitmap u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 9aa2895aefce4bdf written 24 min_key POS_MIN durability: 1 ptr: 0:41:0 gen 0, fixing bcachefs (loop0): btree ptr not marked in member info btree allocated bitmap u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq c0bef60d07ceb940 written 16 min_key POS_MIN durability: 1 ptr: 0:35:0 gen 0, fixing done bcachefs (loop0): going read-write bcachefs (loop0): journal_replay... done bcachefs (loop0): check_alloc_info... done bcachefs (loop0): check_lrus... done bcachefs (loop0): check_backpointers_to_extents... done bcachefs (loop0): check_extents_to_backpointers... bcachefs (loop0): scanning for missing backpointers in 3/128 buckets done bcachefs (loop0): check_alloc_to_lru_refs... done bcachefs (loop0): reconstruct_snapshots... bcachefs (loop0): snapshot node 4294967295 from tree 4294967295 missing, recreating done bcachefs (loop0): Fixed errors, running fsck a second time to verify fs is clean bcachefs (loop0): check_alloc_info... done bcachefs (loop0): check_lrus... done bcachefs (loop0): check_backpointers_to_extents... done bcachefs (loop0): check_extents_to_backpointers... done bcachefs (loop0): check_alloc_to_lru_refs... done bcachefs (loop0): reconstruct_snapshots... done bcachefs (loop0): scanning for old btree nodes: min_version 0.11: inode_btree_change bcachefs (loop0): scanning for old btree nodes done bcachefs (loop0): done starting filesystem evm: overlay not supported ============================================ WARNING: possible recursive locking detected 6.15.0-rc2-syzkaller #0 Not tainted -------------------------------------------- syz.0.0/5327 is trying to acquire lock: ffff888045071810 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] ffff888045071810 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: bch2_symlink+0x178/0x320 fs/bcachefs/fs.c:858 but task is already holding lock: ffff8880450708e0 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] ffff8880450708e0 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: ovl_copy_up_workdir fs/overlayfs/copy_up.c:782 [inline] ffff8880450708e0 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: ovl_do_copy_up fs/overlayfs/copy_up.c:1001 [inline] ffff8880450708e0 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: ovl_copy_up_one fs/overlayfs/copy_up.c:1202 [inline] ffff8880450708e0 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: ovl_copy_up_flags+0x19d7/0x47f0 fs/overlayfs/copy_up.c:1257 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&sb->s_type->i_mutex_key#21); lock(&sb->s_type->i_mutex_key#21); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by syz.0.0/5327: #0: ffff88805301c420 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556 #1: ffff88805550e418 (&ovl_i_mutex_key[depth]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff88805550e418 (&ovl_i_mutex_key[depth]){+.+.}-{4:4}, at: chown_common+0x3e3/0x850 fs/open.c:772 #2: ffff88805550e7d0 (&ovl_i_lock_key[depth]){+.+.}-{4:4}, at: ovl_inode_lock_interruptible fs/overlayfs/overlayfs.h:651 [inline] #2: ffff88805550e7d0 (&ovl_i_lock_key[depth]){+.+.}-{4:4}, at: ovl_copy_up_start+0x53/0x310 fs/overlayfs/util.c:727 #3: ffff888056610420 (sb_writers#12){.+.+}-{0:0}, at: ovl_copy_up_workdir fs/overlayfs/copy_up.c:781 [inline] #3: ffff888056610420 (sb_writers#12){.+.+}-{0:0}, at: ovl_do_copy_up fs/overlayfs/copy_up.c:1001 [inline] #3: ffff888056610420 (sb_writers#12){.+.+}-{0:0}, at: ovl_copy_up_one fs/overlayfs/copy_up.c:1202 [inline] #3: ffff888056610420 (sb_writers#12){.+.+}-{0:0}, at: ovl_copy_up_flags+0x19c0/0x47f0 fs/overlayfs/copy_up.c:1257 #4: ffff8880450708e0 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #4: ffff8880450708e0 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: ovl_copy_up_workdir fs/overlayfs/copy_up.c:782 [inline] #4: ffff8880450708e0 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: ovl_do_copy_up fs/overlayfs/copy_up.c:1001 [inline] #4: ffff8880450708e0 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: ovl_copy_up_one fs/overlayfs/copy_up.c:1202 [inline] #4: ffff8880450708e0 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: ovl_copy_up_flags+0x19d7/0x47f0 fs/overlayfs/copy_up.c:1257 stack backtrace: CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 Not tainted 6.15.0-rc2-syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_deadlock_bug+0x2be/0x2d0 kernel/locking/lockdep.c:3042 check_deadlock kernel/locking/lockdep.c:3094 [inline] validate_chain+0x928/0x24e0 kernel/locking/lockdep.c:3896 __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235 lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 down_write+0x9c/0x220 kernel/locking/rwsem.c:1577 inode_lock include/linux/fs.h:867 [inline] bch2_symlink+0x178/0x320 fs/bcachefs/fs.c:858 vfs_symlink+0x137/0x2e0 fs/namei.c:4688 ovl_do_symlink+0x85/0xd0 fs/overlayfs/overlayfs.h:268 ovl_create_real+0x271/0x460 fs/overlayfs/dir.c:176 ovl_copy_up_workdir fs/overlayfs/copy_up.c:783 [inline] ovl_do_copy_up fs/overlayfs/copy_up.c:1001 [inline] ovl_copy_up_one fs/overlayfs/copy_up.c:1202 [inline] ovl_copy_up_flags+0x1a0a/0x47f0 fs/overlayfs/copy_up.c:1257 ovl_setattr+0x11d/0x5a0 fs/overlayfs/inode.c:40 notify_change+0xbca/0xe90 fs/attr.c:552 chown_common+0x503/0x850 fs/open.c:782 do_fchownat+0x16c/0x250 fs/open.c:813 __do_sys_lchown fs/open.c:838 [inline] __se_sys_lchown fs/open.c:836 [inline] __x64_sys_lchown+0x85/0xa0 fs/open.c:836 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5c8398d169 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:00007f5c84786038 EFLAGS: 00000246 ORIG_RAX: 000000000000005e RAX: ffffffffffffffda RBX: 00007f5c83ba5fa0 RCX: 00007f5c8398d169 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000340 RBP: 00007f5c83a0e990 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5c83ba5fa0 R15: 00007ffcc1e2cac8 overlay: filesystem on ./bus not supported as upperdir syz.0.0 (5327) used greatest stack depth: 11992 bytes left