syzbot


general protection fault in bnep_session

Status: upstream: reported on 2025/08/22 09:32
Reported-by: syzbot+1781ef2931c2a5cdd68d@syzkaller.appspotmail.com
First crash: 10d, last: 10d
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in bnep_session kernel 2 syz 841 17h15m 281d 0/29 upstream: reported syz repro on 2024/11/23 23:04
linux-6.6 general protection fault in bnep_session 2 4 5d02h 65d 0/2 upstream: reported on 2025/06/28 12:06
linux-5.15 general protection fault in bnep_session 2 2 144d 192d 0/3 auto-obsoleted due to no activity on 2025/07/19 02:50

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc000000000b: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000058-0x000000000000005f]
CPU: 0 PID: 8031 Comm: kbnepd bnep0 Not tainted 6.1.148-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:klist_put lib/klist.c:212 [inline]
RIP: 0010:klist_del+0x45/0x110 lib/klist.c:230
Code: 7e f7 49 89 dc 49 c1 ec 03 43 80 3c 3c 00 74 08 48 89 df e8 1d a8 ce f7 4c 8b 33 49 83 e6 fe 49 8d 7e 58 48 89 f8 48 c1 e8 03 <42> 80 3c 38 00 74 05 e8 ff a7 ce f7 49 8b 46 58 48 89 04 24 4c 89
RSP: 0018:ffffc9000556f900 EFLAGS: 00010202
RAX: 000000000000000b RBX: ffff8880300c1860 RCX: ffff8880792ed940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000058
RBP: ffffc9000556fa30 R08: dffffc0000000000 R09: ffffed10060c4075
R10: ffffed10060c4075 R11: 1ffff110060c4074 R12: 1ffff1100601830c
R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3451dff8 CR3: 000000002430a000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 device_del+0x2e0/0xa70 drivers/base/core.c:3864
 unregister_netdevice_many+0x1393/0x1840 net/core/dev.c:11005
 unregister_netdevice_queue net/core/dev.c:10909 [inline]
 unregister_netdevice include/linux/netdevice.h:3075 [inline]
 unregister_netdev+0x140/0x1b0 net/core/dev.c:11037
 bnep_session+0x2974/0x2b60 net/bluetooth/bnep/core.c:525
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:klist_put lib/klist.c:212 [inline]
RIP: 0010:klist_del+0x45/0x110 lib/klist.c:230
Code: 7e f7 49 89 dc 49 c1 ec 03 43 80 3c 3c 00 74 08 48 89 df e8 1d a8 ce f7 4c 8b 33 49 83 e6 fe 49 8d 7e 58 48 89 f8 48 c1 e8 03 <42> 80 3c 38 00 74 05 e8 ff a7 ce f7 49 8b 46 58 48 89 04 24 4c 89
RSP: 0018:ffffc9000556f900 EFLAGS: 00010202
RAX: 000000000000000b RBX: ffff8880300c1860 RCX: ffff8880792ed940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000058
RBP: ffffc9000556fa30 R08: dffffc0000000000 R09: ffffed10060c4075
R10: ffffed10060c4075 R11: 1ffff110060c4074 R12: 1ffff1100601830c
R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3451dff8 CR3: 0000000060848000 CR4: 00000000003506f0
----------------
Code disassembly (best guess):
   0:	7e f7                	jle    0xfffffff9
   2:	49 89 dc             	mov    %rbx,%r12
   5:	49 c1 ec 03          	shr    $0x3,%r12
   9:	43 80 3c 3c 00       	cmpb   $0x0,(%r12,%r15,1)
   e:	74 08                	je     0x18
  10:	48 89 df             	mov    %rbx,%rdi
  13:	e8 1d a8 ce f7       	call   0xf7cea835
  18:	4c 8b 33             	mov    (%rbx),%r14
  1b:	49 83 e6 fe          	and    $0xfffffffffffffffe,%r14
  1f:	49 8d 7e 58          	lea    0x58(%r14),%rdi
  23:	48 89 f8             	mov    %rdi,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 38 00       	cmpb   $0x0,(%rax,%r15,1) <-- trapping instruction
  2f:	74 05                	je     0x36
  31:	e8 ff a7 ce f7       	call   0xf7cea835
  36:	49 8b 46 58          	mov    0x58(%r14),%rax
  3a:	48 89 04 24          	mov    %rax,(%rsp)
  3e:	4c                   	rex.WR
  3f:	89                   	.byte 0x89

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/22 09:31 linux-6.1.y 0bc96de781b4 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan general protection fault in bnep_session
* Struck through repros no longer work on HEAD.