syzbot


general protection fault in bcsp_recv

Status: upstream: reported on 2025/07/01 16:33
Reported-by: syzbot+5d6ea866b1b60f71e271@syzkaller.appspotmail.com
First crash: 21h01m, last: 21h01m
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 BUG: unable to handle kernel paging request in bcsp_recv origin:upstream C 12 16d 65d 0/3 upstream: reported C repro on 2025/04/27 13:45
linux-5.15 general protection fault in bcsp_recv origin:upstream C 7 14d 19d 0/3 upstream: reported C repro on 2025/06/13 12:03
upstream general protection fault in bcsp_recv bluetooth C error 444 3h03m 136d 0/29 upstream: reported C repro on 2025/02/15 17:18

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000021: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f]
CPU: 1 PID: 8105 Comm: syz.1.788 Not tainted 6.6.95-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:bcsp_recv+0x13e/0x1730 drivers/bluetooth/hci_bcsp.c:590
Code: 89 4c 24 40 48 89 54 24 28 48 c1 ea 03 48 89 54 24 68 48 89 5c 24 20 48 c1 eb 03 48 89 5c 24 60 4c 89 7c 24 38 48 8b 44 24 58 <42> 80 3c 30 00 74 08 4c 89 ff e8 93 fa 59 fa 49 8b 1f 31 ff 48 89
RSP: 0018:ffffc90010837c20 EFLAGS: 00010206
RAX: 0000000000000021 RBX: 0000000000000030 RCX: 000000000000002f
RDX: 000000000000002f RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90010837d80 R08: ffff88802a6af41f R09: 1ffff110054d5e83
R10: dffffc0000000000 R11: ffffed10054d5e84 R12: 0000000000000001
R13: ffffc90010837e20 R14: dffffc0000000000 R15: 0000000000000108
FS:  00007fc5571696c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc557168f98 CR3: 000000005b5ed000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 hci_uart_tty_receive+0x188/0x210 drivers/bluetooth/hci_ldisc.c:624
 tiocsti+0x23e/0x2c0 drivers/tty/tty_io.c:2291
 tty_ioctl+0x62e/0xdd0 drivers/tty/tty_io.c:2693
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc55638e929
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:00007fc557169038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fc5565b6080 RCX: 00007fc55638e929
RDX: 0000200000000500 RSI: 0000000000005412 RDI: 0000000000000003
RBP: 00007fc556410b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fc5565b6080 R15: 00007ffc1e714518
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:bcsp_recv+0x13e/0x1730 drivers/bluetooth/hci_bcsp.c:590
Code: 89 4c 24 40 48 89 54 24 28 48 c1 ea 03 48 89 54 24 68 48 89 5c 24 20 48 c1 eb 03 48 89 5c 24 60 4c 89 7c 24 38 48 8b 44 24 58 <42> 80 3c 30 00 74 08 4c 89 ff e8 93 fa 59 fa 49 8b 1f 31 ff 48 89
RSP: 0018:ffffc90010837c20 EFLAGS: 00010206
RAX: 0000000000000021 RBX: 0000000000000030 RCX: 000000000000002f
RDX: 000000000000002f RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90010837d80 R08: ffff88802a6af41f R09: 1ffff110054d5e83
R10: dffffc0000000000 R11: ffffed10054d5e84 R12: 0000000000000001
R13: ffffc90010837e20 R14: dffffc0000000000 R15: 0000000000000108
FS:  00007fc5571696c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c370005 CR3: 000000005b5ed000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	89 4c 24 40          	mov    %ecx,0x40(%rsp)
   4:	48 89 54 24 28       	mov    %rdx,0x28(%rsp)
   9:	48 c1 ea 03          	shr    $0x3,%rdx
   d:	48 89 54 24 68       	mov    %rdx,0x68(%rsp)
  12:	48 89 5c 24 20       	mov    %rbx,0x20(%rsp)
  17:	48 c1 eb 03          	shr    $0x3,%rbx
  1b:	48 89 5c 24 60       	mov    %rbx,0x60(%rsp)
  20:	4c 89 7c 24 38       	mov    %r15,0x38(%rsp)
  25:	48 8b 44 24 58       	mov    0x58(%rsp),%rax
* 2a:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 ff             	mov    %r15,%rdi
  34:	e8 93 fa 59 fa       	call   0xfa59facc
  39:	49 8b 1f             	mov    (%r15),%rbx
  3c:	31 ff                	xor    %edi,%edi
  3e:	48                   	rex.W
  3f:	89                   	.byte 0x89

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/01 16:33 linux-6.6.y 3f5b4c104b7d 091a06cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in bcsp_recv
* Struck through repros no longer work on HEAD.