Oops: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 1 UID: 0 PID: 6776 Comm: syz.2.166 Not tainted 6.13.0-rc3-next-20241220-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:btrfs_root_node+0x86/0x3b0 fs/btrfs/ctree.c:193
Code: 80 a9 c7 fd 48 83 c4 08 e8 f7 0c 1f 08 89 c3 31 ff 89 c6 e8 7c 47 ec fd 85 db 74 17 e8 c3 0b d2 fd 84 c0 74 1c e8 2a 43 ec fd <43> 80 3c 3c 00 75 4b eb 51 e8 1c 43 ec fd 43 80 3c 3c 00 75 3d eb
RSP: 0018:ffffc9000526f6c0 EFLAGS: 00010293
RAX: ffffffff83d2e0f6 RBX: 0000000000000001 RCX: ffff8880316a1e00
RDX: 0000000000000000 RSI: ffffffff8c5fece0 RDI: ffffffff8c5feca0
RBP: ffffc9000526f8b0 R08: ffffffff83d2e0e4 R09: 1ffffffff285af08
R10: dffffc0000000000 R11: fffffbfff285af09 R12: 0000000000000003
R13: dffffc0000000000 R14: 0000000000000018 R15: dffffc0000000000
FS:  00007f6fa6b526c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c337859 CR3: 00000000288ee000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 btrfs_read_lock_root_node+0x27/0xd0 fs/btrfs/locking.c:264
 btrfs_build_ref_tree+0x112/0x16f0 fs/btrfs/ref-verify.c:1006
 open_ctree+0x1ff5/0x2a70 fs/btrfs/disk-io.c:3504
 btrfs_fill_super fs/btrfs/super.c:972 [inline]
 btrfs_get_tree_super fs/btrfs/super.c:1898 [inline]
 btrfs_get_tree+0x12da/0x1a30 fs/btrfs/super.c:2093
 vfs_get_tree+0x90/0x2b0 fs/super.c:1814
 fc_mount+0x1b/0xb0 fs/namespace.c:1272
 btrfs_get_tree_subvol fs/btrfs/super.c:2051 [inline]
 btrfs_get_tree+0x6b1/0x1a30 fs/btrfs/super.c:2094
 vfs_get_tree+0x90/0x2b0 fs/super.c:1814
 do_new_mount+0x2be/0xb40 fs/namespace.c:3556
 do_mount fs/namespace.c:3896 [inline]
 __do_sys_mount fs/namespace.c:4107 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4084
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6fa5d874ca
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:00007f6fa6b51e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f6fa6b51ef0 RCX: 00007f6fa5d874ca
RDX: 0000000020000080 RSI: 0000000020000040 RDI: 00007f6fa6b51eb0
RBP: 0000000020000080 R08: 00007f6fa6b51ef0 R09: 000000000001c005
R10: 000000000001c005 R11: 0000000000000246 R12: 0000000020000040
R13: 00007f6fa6b51eb0 R14: 00000000000055cb R15: 0000000020000100
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:btrfs_root_node+0x86/0x3b0 fs/btrfs/ctree.c:193
Code: 80 a9 c7 fd 48 83 c4 08 e8 f7 0c 1f 08 89 c3 31 ff 89 c6 e8 7c 47 ec fd 85 db 74 17 e8 c3 0b d2 fd 84 c0 74 1c e8 2a 43 ec fd <43> 80 3c 3c 00 75 4b eb 51 e8 1c 43 ec fd 43 80 3c 3c 00 75 3d eb
RSP: 0018:ffffc9000526f6c0 EFLAGS: 00010293
RAX: ffffffff83d2e0f6 RBX: 0000000000000001 RCX: ffff8880316a1e00
RDX: 0000000000000000 RSI: ffffffff8c5fece0 RDI: ffffffff8c5feca0
RBP: ffffc9000526f8b0 R08: ffffffff83d2e0e4 R09: 1ffffffff285af08
R10: dffffc0000000000 R11: fffffbfff285af09 R12: 0000000000000003
R13: dffffc0000000000 R14: 0000000000000018 R15: dffffc0000000000
FS:  00007f6fa6b526c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcabf948178 CR3: 00000000288ee000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	80 a9 c7 fd 48 83 c4 	subb   $0xc4,-0x7cb70239(%rcx)
   7:	08 e8                	or     %ch,%al
   9:	f7 0c 1f 08 89 c3 31 	testl  $0x31c38908,(%rdi,%rbx,1)
  10:	ff 89 c6 e8 7c 47    	decl   0x477ce8c6(%rcx)
  16:	ec                   	in     (%dx),%al
  17:	fd                   	std
  18:	85 db                	test   %ebx,%ebx
  1a:	74 17                	je     0x33
  1c:	e8 c3 0b d2 fd       	call   0xfdd20be4
  21:	84 c0                	test   %al,%al
  23:	74 1c                	je     0x41
  25:	e8 2a 43 ec fd       	call   0xfdec4354
* 2a:	43 80 3c 3c 00       	cmpb   $0x0,(%r12,%r15,1) <-- trapping instruction
  2f:	75 4b                	jne    0x7c
  31:	eb 51                	jmp    0x84
  33:	e8 1c 43 ec fd       	call   0xfdec4354
  38:	43 80 3c 3c 00       	cmpb   $0x0,(%r12,%r15,1)
  3d:	75 3d                	jne    0x7c
  3f:	eb                   	.byte 0xeb