BTRFS info (device loop6): using free-space-tree
BTRFS error (device loop6): failed to load root extent
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 1 UID: 0 PID: 10327 Comm: syz.6.872 Not tainted 6.16.0-syzkaller-04405-g4b290aae788e #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:btrfs_root_node+0x151/0x4a0 fs/btrfs/ctree.c:193
Code: 24 e8 83 72 04 fe c6 05 ce de ce 0b 01 48 c7 c7 00 fa cc 8b be 4b 03 00 00 48 c7 c2 40 fa cc 8b e8 d4 5c e2 fd 48 8b 44 24 18 <42> 80 3c 30 00 74 08 4c 89 e7 e8 40 85 66 fe 4d 8b 2c 24 e8 47 06
RSP: 0018:ffffc90004fc7800 EFLAGS: 00010287
RAX: 0000000000000003 RBX: ffffffff83bb48de RCX: 0000000000080000
RDX: ffffc90020232000 RSI: 0000000000030355 RDI: 0000000000030356
RBP: ffffc90004fc78c0 R08: 0000000000000000 R09: ffffffff83bb48de
R10: dffffc0000000000 R11: ffffed100a98200e R12: 0000000000000018
R13: ffff888026b80000 R14: dffffc0000000000 R15: 0000000000000001
FS:  00007f15fd8796c0(0000) GS:ffff888125d86000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7b2fb18360 CR3: 000000005f297000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 btrfs_read_lock_root_node+0x27/0xd0 fs/btrfs/locking.c:263
 btrfs_build_ref_tree+0x113/0x1680 fs/btrfs/ref-verify.c:988
 open_ctree+0x2504/0x3a10 fs/btrfs/disk-io.c:3594
 btrfs_fill_super fs/btrfs/super.c:977 [inline]
 btrfs_get_tree_super fs/btrfs/super.c:1937 [inline]
 btrfs_get_tree_subvol fs/btrfs/super.c:2074 [inline]
 btrfs_get_tree+0xf55/0x1820 fs/btrfs/super.c:2108
 vfs_get_tree+0x92/0x2b0 fs/super.c:1815
 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4321
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f15fc99014a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f15fd878e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f15fd878ef0 RCX: 00007f15fc99014a
RDX: 0000200000000000 RSI: 0000200000000040 RDI: 00007f15fd878eb0
RBP: 0000200000000000 R08: 00007f15fd878ef0 R09: 000000000001c005
R10: 000000000001c005 R11: 0000000000000246 R12: 0000200000000040
R13: 00007f15fd878eb0 R14: 00000000000055ae R15: 00002000000003c0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:btrfs_root_node+0x151/0x4a0 fs/btrfs/ctree.c:193
Code: 24 e8 83 72 04 fe c6 05 ce de ce 0b 01 48 c7 c7 00 fa cc 8b be 4b 03 00 00 48 c7 c2 40 fa cc 8b e8 d4 5c e2 fd 48 8b 44 24 18 <42> 80 3c 30 00 74 08 4c 89 e7 e8 40 85 66 fe 4d 8b 2c 24 e8 47 06
RSP: 0018:ffffc90004fc7800 EFLAGS: 00010287
RAX: 0000000000000003 RBX: ffffffff83bb48de RCX: 0000000000080000
RDX: ffffc90020232000 RSI: 0000000000030355 RDI: 0000000000030356
RBP: ffffc90004fc78c0 R08: 0000000000000000 R09: ffffffff83bb48de
R10: dffffc0000000000 R11: ffffed100a98200e R12: 0000000000000018
R13: ffff888026b80000 R14: dffffc0000000000 R15: 0000000000000001
FS:  00007f15fd8796c0(0000) GS:ffff888125d86000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c0494ae000 CR3: 000000005f297000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	24 e8                	and    $0xe8,%al
   2:	83 72 04 fe          	xorl   $0xfffffffe,0x4(%rdx)
   6:	c6 05 ce de ce 0b 01 	movb   $0x1,0xbcedece(%rip)        # 0xbcededb
   d:	48 c7 c7 00 fa cc 8b 	mov    $0xffffffff8bccfa00,%rdi
  14:	be 4b 03 00 00       	mov    $0x34b,%esi
  19:	48 c7 c2 40 fa cc 8b 	mov    $0xffffffff8bccfa40,%rdx
  20:	e8 d4 5c e2 fd       	call   0xfde25cf9
  25:	48 8b 44 24 18       	mov    0x18(%rsp),%rax
* 2a:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 e7             	mov    %r12,%rdi
  34:	e8 40 85 66 fe       	call   0xfe668579
  39:	4d 8b 2c 24          	mov    (%r12),%r13
  3d:	e8                   	.byte 0xe8
  3e:	47 06                	rex.RXB (bad)