syzbot


kernel BUG in pn_socket_sendmsg

Status: upstream: reported C repro on 2026/04/21 23:16
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+706f5eb79044e686c794@syzkaller.appspotmail.com
Fix commit: net: phonet: do not BUG_ON() in pn_socket_autobind() on failed bind
Patched on: [ci-upstream-linux-next-kasan-gce-root ci-upstream-net-this-kasan-gce ci-upstream-rust-kasan-gce], missing on: [ci-qemu-gce-upstream-auto ci-qemu-native-arm64-kvm ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-qemu2-riscv64 ci-snapshot-upstream-root ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-arm64 ci-upstream-gce-leak ci-upstream-kasan-badwrites-root ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-kmsan-gce-386-root ci-upstream-kmsan-gce-root ci-upstream-net-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb]
First crash: 11d, last: 1d17h
Discussions (3)
Title Replies (including bot) Last reply
[PATCH] net: phonet: fix BUG_ON() in pn_socket_autobind() 4 (4) 2026/04/28 08:48
[PATCH] net: phonet: do not BUG_ON() in pn_socket_autobind() on failed bind 7 (7) 2026/04/28 01:50
[syzbot] [net?] kernel BUG in pn_socket_sendmsg 0 (3) 2026/04/22 02:13
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 kernel BUG in pn_socket_sendmsg -1 C 3 10d 10d 0/3 upstream: reported C repro on 2026/04/19 04:56
Last patch testing requests (2)
Created Duration User Patch Repo Result
2026/04/22 02:13 49m kartikey406@gmail.com patch linux-next report log
2026/04/22 02:12 38m kartikey406@gmail.com patch https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master report log

Sample crash report:
netlink: 'syz.0.17': attribute type 2 has an invalid length.
------------[ cut here ]------------
kernel BUG at net/phonet/socket.c:213!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 6014 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:pn_socket_autobind net/phonet/socket.c:213 [inline]
RIP: 0010:pn_socket_sendmsg+0x240/0x250 net/phonet/socket.c:421
Code: cc cc cc e8 c2 0c d2 00 89 d9 80 e1 07 fe c1 38 c1 0f 8c 04 ff ff ff 48 89 df e8 bb d3 be f7 e9 f7 fe ff ff e8 c1 5a 55 f7 90 <0f> 0b 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90
RSP: 0018:ffffc900050d7ba0 EFLAGS: 00010293
RAX: ffffffff8a6fa75f RBX: 0000000000000000 RCX: ffff888031b91ec0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900050d7c58 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f9e8df R12: dffffc0000000000
R13: ffff88805c7b5ec0 R14: ffff888034fecec0 R15: 1ffff92000a1af78
FS:  00007f347ac666c0(0000) GS:ffff888125a62000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f347b5f7680 CR3: 000000003d362000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 sock_sendmsg_nosec+0x112/0x150 net/socket.c:797
 __sock_sendmsg net/socket.c:812 [inline]
 __sys_sendto+0x402/0x590 net/socket.c:2280
 __do_sys_sendto net/socket.c:2287 [inline]
 __se_sys_sendto net/socket.c:2283 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2283
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f347b5cd04e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007f347ac64e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f347ac666c0 RCX: 00007f347b5cd04e
RDX: 0000000000000020 RSI: 00007f347ac65000 RDI: 0000000000000006
RBP: 0000000000000000 R08: 00007f347ac64f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 00007f347ac64f58 R14: 00007f347ac65000 R15: 0000000000000000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:pn_socket_autobind net/phonet/socket.c:213 [inline]
RIP: 0010:pn_socket_sendmsg+0x240/0x250 net/phonet/socket.c:421
Code: cc cc cc e8 c2 0c d2 00 89 d9 80 e1 07 fe c1 38 c1 0f 8c 04 ff ff ff 48 89 df e8 bb d3 be f7 e9 f7 fe ff ff e8 c1 5a 55 f7 90 <0f> 0b 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90
RSP: 0018:ffffc900050d7ba0 EFLAGS: 00010293
RAX: ffffffff8a6fa75f RBX: 0000000000000000 RCX: ffff888031b91ec0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900050d7c58 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f9e8df R12: dffffc0000000000
R13: ffff88805c7b5ec0 R14: ffff888034fecec0 R15: 1ffff92000a1af78
FS:  00007f347ac666c0(0000) GS:ffff888125a62000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f347b5f7680 CR3: 000000003d362000 CR4: 00000000003526f0

Crashes (18):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/21 07:10 linux-next 97e797263a5e 3f2e655b .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce kernel BUG in pn_socket_sendmsg
2026/04/27 17:37 upstream 254f49634ee1 0f700595 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/26 12:20 upstream 897d54018cc9 9c2d0995 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/26 02:55 upstream 897d54018cc9 9c2d0995 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/24 13:49 upstream dd6c438c3e64 9cfb3ca7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/24 12:53 upstream dd6c438c3e64 9cfb3ca7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/23 18:31 upstream 2e6803928193 629ff21a .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/23 05:40 upstream 2a4c0c11c019 b10da5ec .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/21 22:15 upstream b4e07588e743 9765efe0 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/21 13:22 upstream c1f49dea2b8f 3f2e655b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/21 13:20 upstream c1f49dea2b8f 3f2e655b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/20 02:42 upstream bea8d77e45a8 303e2802 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/20 01:52 upstream bea8d77e45a8 303e2802 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/19 01:03 upstream eb5249b12507 303e2802 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/18 13:05 upstream 8541d8f725c6 5be7a9de .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/18 00:31 upstream 43cfbdda5af6 24ecfc1e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/17 23:03 upstream 43cfbdda5af6 24ecfc1e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
2026/04/17 23:02 upstream 43cfbdda5af6 24ecfc1e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in pn_socket_sendmsg
* Struck through repros no longer work on HEAD.