[syzbot] [hfs?] kernel BUG in hfs_btree_open (2)

From: syzbot
Date: Mon Sep 11 2023 - 21:18:27 EST


Hello,

syzbot found the following issue on:

HEAD commit: 0bb80ecc33a8 Linux 6.6-rc1
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16abc6c7a80000
kernel config: https://syzkaller.appspot.com/x/.config?x=df91a3034fe3f122
dashboard link: https://syzkaller.appspot.com/bug?extid=f8aee4b1409f7e8e6e46
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1d506cf29d25/disk-0bb80ecc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ca5b56af4b3e/vmlinux-0bb80ecc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/aa88aed611c1/bzImage-0bb80ecc.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f8aee4b1409f7e8e6e46@xxxxxxxxxxxxxxxxxxxxxxxxx

loop2: detected capacity change from 0 to 64
------------[ cut here ]------------
kernel BUG at fs/hfs/btree.c:41!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 11852 Comm: syz-executor.2 Not tainted 6.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
RIP: 0010:hfs_btree_open+0xf09/0xf20 fs/hfs/btree.c:41
Code: 7e ff e9 7e fa ff ff 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 9b fa ff ff 4c 89 f7 e8 c1 ca 7e ff e9 8e fa ff ff e8 c7 df 24 ff <0f> 0b e8 c0 df 24 ff 0f 0b e8 b9 df 24 ff 0f 0b 0f 1f 80 00 00 00
RSP: 0000:ffffc900034cf738 EFLAGS: 00010283
RAX: ffffffff8268c3c9 RBX: ffff888036585ad0 RCX: 0000000000040000
RDX: ffffc9000b664000 RSI: 000000000000586c RDI: 000000000000586d
RBP: 0000000000000000 R08: ffffffff8268b627 R09: 1ffff11006cb0b75
R10: dffffc0000000000 R11: ffffed1006cb0b76 R12: ffff8880210a2000
R13: ffff888028f54008 R14: ffff888028f54000 R15: dffffc0000000000
FS: 00007f73a031a6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8c2a9ba000 CR3: 0000000023db4000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
hfs_mdb_get+0x1443/0x21b0 fs/hfs/mdb.c:199
hfs_fill_super+0x107d/0x1790 fs/hfs/super.c:406
mount_bdev+0x237/0x300 fs/super.c:1629
legacy_get_tree+0xef/0x190 fs/fs_context.c:638
vfs_get_tree+0x8c/0x280 fs/super.c:1750
do_new_mount+0x28f/0xae0 fs/namespace.c:3335
do_mount fs/namespace.c:3675 [inline]
__do_sys_mount fs/namespace.c:3884 [inline]
__se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3861
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f739f67e1ea
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 09 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f73a0319ee8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f73a0319f80 RCX: 00007f739f67e1ea
RDX: 0000000020000240 RSI: 0000000020000040 RDI: 00007f73a0319f40
RBP: 0000000020000240 R08: 00007f73a0319f80 R09: 0000000000004012
R10: 0000000000004012 R11: 0000000000000202 R12: 0000000020000040
R13: 00007f73a0319f40 R14: 0000000000000285 R15: 0000000020000000
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:hfs_btree_open+0xf09/0xf20 fs/hfs/btree.c:41
Code: 7e ff e9 7e fa ff ff 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 9b fa ff ff 4c 89 f7 e8 c1 ca 7e ff e9 8e fa ff ff e8 c7 df 24 ff <0f> 0b e8 c0 df 24 ff 0f 0b e8 b9 df 24 ff 0f 0b 0f 1f 80 00 00 00
RSP: 0000:ffffc900034cf738 EFLAGS: 00010283
RAX: ffffffff8268c3c9 RBX: ffff888036585ad0 RCX: 0000000000040000
RDX: ffffc9000b664000 RSI: 000000000000586c RDI: 000000000000586d
RBP: 0000000000000000 R08: ffffffff8268b627 R09: 1ffff11006cb0b75
R10: dffffc0000000000 R11: ffffed1006cb0b76 R12: ffff8880210a2000
R13: ffff888028f54008 R14: ffff888028f54000 R15: dffffc0000000000
FS: 00007f73a031a6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff38ded7086 CR3: 0000000023db4000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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