syzbot


kernel BUG in pn_socket_sendmsg

Status: upstream: reported C repro on 2026/05/24 06:57
Reported-by: syzbot+8f8816d1a6eb0c8ceb3e@syzkaller.appspotmail.com
First crash: 2d23h, last: 12h47m
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 kernel BUG in pn_socket_sendmsg -1 C error 16 12h25m 38d 0/3 upstream: reported C repro on 2026/04/19 04:56
upstream kernel BUG in pn_socket_sendmsg net -1 C 19 27d 35d 29/29 fixed on 2026/05/22 04:12
linux-5.15 kernel BUG in pn_socket_sendmsg -1 6 1d08h 3d05h 0/3 upstream: reported on 2026/05/24 01:22

Sample crash report:
netlink: 'syz.0.17': attribute type 2 has an invalid length.
------------[ cut here ]------------
kernel BUG at net/phonet/socket.c:213!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 5934 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:pn_socket_autobind net/phonet/socket.c:213 [inline]
RIP: 0010:pn_socket_sendmsg+0x235/0x240 net/phonet/socket.c:422
Code: 41 5f 5d c3 e8 bc 6a cb 00 89 d9 80 e1 07 fe c1 38 c1 0f 8c 0f ff ff ff 48 89 df e8 25 8b 23 f8 e9 02 ff ff ff e8 0b 4c cb f7 <0f> 0b 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 55 48 89 e5 41 57 41
RSP: 0018:ffffc90003397960 EFLAGS: 00010293
RAX: ffffffff89bbdfe5 RBX: 0000000000000000 RCX: ffff88802c875a00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003397a10 R08: ffffffff8e8b3aef R09: 1ffffffff1d1675d
R10: dffffc0000000000 R11: fffffbfff1d1675e R12: dffffc0000000000
R13: ffff88805dcce000 R14: ffff88807abb0c80 R15: 1ffff92000672f30
FS:  00007fb751ba06c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb751b7eff8 CR3: 00000000739d3000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x5ba/0x960 net/socket.c:2594
 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2648
 __sys_sendmsg net/socket.c:2677 [inline]
 __do_sys_sendmsg net/socket.c:2686 [inline]
 __se_sys_sendmsg+0x1c2/0x2b0 net/socket.c:2684
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb750d9ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb751ba0028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fb751015fa0 RCX: 00007fb750d9ce59
RDX: 0000000004004081 RSI: 00002000000002c0 RDI: 0000000000000006
RBP: 00007fb750e32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb751016038 R14: 00007fb751015fa0 R15: 00007ffeb68fa408
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:pn_socket_autobind net/phonet/socket.c:213 [inline]
RIP: 0010:pn_socket_sendmsg+0x235/0x240 net/phonet/socket.c:422
Code: 41 5f 5d c3 e8 bc 6a cb 00 89 d9 80 e1 07 fe c1 38 c1 0f 8c 0f ff ff ff 48 89 df e8 25 8b 23 f8 e9 02 ff ff ff e8 0b 4c cb f7 <0f> 0b 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 55 48 89 e5 41 57 41
RSP: 0018:ffffc90003397960 EFLAGS: 00010293
RAX: ffffffff89bbdfe5 RBX: 0000000000000000 RCX: ffff88802c875a00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003397a10 R08: ffffffff8e8b3aef R09: 1ffffffff1d1675d
R10: dffffc0000000000 R11: fffffbfff1d1675e R12: dffffc0000000000
R13: ffff88805dcce000 R14: ffff88807abb0c80 R15: 1ffff92000672f30
FS:  00007fb751ba06c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb750dea540 CR3: 00000000739d3000 CR4: 00000000003506f0

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/24 08:24 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in pn_socket_sendmsg
2026/05/26 18:02 linux-6.6.y 0a40c6fbd105 a3e47276 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in pn_socket_sendmsg
2026/05/25 23:37 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in pn_socket_sendmsg
2026/05/25 23:35 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in pn_socket_sendmsg
2026/05/25 23:32 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in pn_socket_sendmsg
2026/05/25 08:47 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in pn_socket_sendmsg
2026/05/25 08:44 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in pn_socket_sendmsg
2026/05/24 13:47 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in pn_socket_sendmsg
2026/05/24 07:08 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in pn_socket_sendmsg
2026/05/24 07:05 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in pn_socket_sendmsg
2026/05/24 06:56 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan kernel BUG in pn_socket_sendmsg
* Struck through repros no longer work on HEAD.