[syzbot] [bluetooth?] general protection fault in bcsp_recv

[syzbot <syzbot+4ed6852d4da4606c93da@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    df5d6180169a Add linux-next specific files for 20250210
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=17be8718580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2cd616b6e736ca7
dashboard link: https://syzkaller.appspot.com/bug?extid=4ed6852d4da4606c93da
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1480a3f8580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/92495cf20271/disk-df5d6180.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4b3656161842/vmlinux-df5d6180.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7fbc4e7a0f5d/bzImage-df5d6180.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4ed6852d4da4606c93da@syzkaller.appspotmail.com

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000021: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f]
CPU: 0 UID: 0 PID: 6167 Comm: syz.3.45 Not tainted 6.14.0-rc2-next-20250210-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:bcsp_recv+0xcd/0x16d0 drivers/bluetooth/hci_bcsp.c:590
Code: 38 4c 89 e8 48 c1 e8 03 48 89 44 24 28 48 89 4c 24 20 48 89 6c 24 18 4c 89 6c 24 10 4c 89 7c 24 08 89 5c 24 04 48 8b 44 24 38 <42> 80 3c 30 00 74 08 48 89 ef e8 94 d5 5c f9 48 8b 5d 00 31 ff 48
RSP: 0018:ffffc900034d7cd0 EFLAGS: 00010202
RAX: 0000000000000021 RBX: 0000000000000001 RCX: 0000000000000182
RDX: ffff888035fc8000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000108 R08: ffffffff88c9aef5 R09: 1ffff1100ade3c03
R10: dffffc0000000000 R11: ffffffff88c9ae90 R12: ffffc900034d7e00
R13: 0000000000000178 R14: dffffc0000000000 R15: 0000000000000110
FS:  00007f0fbdf626c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000348be000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 hci_uart_tty_receive+0x141/0x1c0 drivers/bluetooth/hci_ldisc.c:622
 tiocsti+0x24d/0x300 drivers/tty/tty_io.c:2299
 tty_ioctl+0x518/0xdc0 drivers/tty/tty_io.c:2716
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:892
 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: 0033:0x7f0fbd18cde9
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:00007f0fbdf62038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f0fbd3a6160 RCX: 00007f0fbd18cde9
RDX: 0000400000000240 RSI: 0000000000005412 RDI: 0000000000000007
RBP: 00007f0fbd20e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0fbd3a6160 R15: 00007fffe8c957b8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:bcsp_recv+0xcd/0x16d0 drivers/bluetooth/hci_bcsp.c:590
Code: 38 4c 89 e8 48 c1 e8 03 48 89 44 24 28 48 89 4c 24 20 48 89 6c 24 18 4c 89 6c 24 10 4c 89 7c 24 08 89 5c 24 04 48 8b 44 24 38 <42> 80 3c 30 00 74 08 48 89 ef e8 94 d5 5c f9 48 8b 5d 00 31 ff 48
RSP: 0018:ffffc900034d7cd0 EFLAGS: 00010202
RAX: 0000000000000021 RBX: 0000000000000001 RCX: 0000000000000182
RDX: ffff888035fc8000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000108 R08: ffffffff88c9aef5 R09: 1ffff1100ade3c03
R10: dffffc0000000000 R11: ffffffff88c9ae90 R12: ffffc900034d7e00
R13: 0000000000000178 R14: dffffc0000000000 R15: 0000000000000110
FS:  00007f0fbdf626c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0fbdf40f98 CR3: 00000000348be000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	38 4c 89 e8          	cmp    %cl,-0x18(%rcx,%rcx,4)
   4:	48 c1 e8 03          	shr    $0x3,%rax
   8:	48 89 44 24 28       	mov    %rax,0x28(%rsp)
   d:	48 89 4c 24 20       	mov    %rcx,0x20(%rsp)
  12:	48 89 6c 24 18       	mov    %rbp,0x18(%rsp)
  17:	4c 89 6c 24 10       	mov    %r13,0x10(%rsp)
  1c:	4c 89 7c 24 08       	mov    %r15,0x8(%rsp)
  21:	89 5c 24 04          	mov    %ebx,0x4(%rsp)
  25:	48 8b 44 24 38       	mov    0x38(%rsp),%rax
* 2a:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	48 89 ef             	mov    %rbp,%rdi
  34:	e8 94 d5 5c f9       	call   0xf95cd5cd
  39:	48 8b 5d 00          	mov    0x0(%rbp),%rbx
  3d:	31 ff                	xor    %edi,%edi
  3f:	48                   	rex.W


---
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