syzbot


kernel BUG in nr_header

Status: upstream: reported on 2024/12/04 14:07
Subsystems: hams
[Documentation on labels]
Reported-by: syzbot+fb99d1b0c0f81d94a5e2@syzkaller.appspotmail.com
Fix commit: a6d75ecee2bf net: lapb: increase LAPB_HEADER_LEN
Patched on: [ci-qemu-gce-upstream-auto ci-qemu-native-arm64-kvm ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte 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-linux-next-kasan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb], missing on: [ci-qemu2-arm32 ci-qemu2-riscv64]
First crash: 112d, last: 30d
Discussions (2)
Title Replies (including bot) Last reply
[PATCH net] net: lapb: increase LAPB_HEADER_LEN 3 (3) 2024/12/07 02:00
[syzbot] [hams?] kernel BUG in nr_header 0 (1) 2024/12/04 14:07

Sample crash report:
skbuff: skb_under_panic: text:ffffffff89fd546a len:24 put:20 head:ffff88802a0b9b00 data:ffff88802a0b9afe tail:0x16 end:0x140 dev:nr0.2
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:205!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 2 UID: 0 PID: 5056 Comm: dhcpcd Not tainted 6.11.0-rc5-syzkaller-00207-gfb24560f31f9 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:skb_panic+0x157/0x1d0 net/core/skbuff.c:205
Code: b6 04 01 84 c0 74 04 3c 03 7e 21 8b 4b 70 41 56 45 89 e8 48 c7 c7 80 3f 7a 8c 41 57 56 48 89 ee 52 4c 89 e2 e8 0a ee 83 f8 90 <0f> 0b 4c 89 4c 24 10 48 89 54 24 08 48 89 34 24 e8 04 38 02 f9 4c
RSP: 0018:ffffc9000404f668 EFLAGS: 00010286
RAX: 0000000000000086 RBX: ffff88802335c780 RCX: ffffffff816c4a19
RDX: 0000000000000000 RSI: ffffffff816cde56 RDI: 0000000000000005
RBP: ffffffff8c7a52a0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000201 R11: 0000000000000000 R12: ffffffff89fd546a
R13: 0000000000000014 R14: ffff88805209a130 R15: 0000000000000140
FS:  00007f4e4cfb9740(0000) GS:ffff88806a800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000203e9000 CR3: 0000000028878000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 skb_under_panic net/core/skbuff.c:215 [inline]
 skb_push+0xca/0xf0 net/core/skbuff.c:2617
 nr_header+0x2a/0x3e0 net/netrom/nr_dev.c:69
 dev_hard_header include/linux/netdevice.h:3159 [inline]
 vlan_dev_hard_header+0x13f/0x520 net/8021q/vlan_dev.c:83
 dev_hard_header include/linux/netdevice.h:3159 [inline]
 lapbeth_data_transmit+0x2a0/0x350 drivers/net/wan/lapbether.c:257
 lapb_data_transmit+0x93/0xc0 net/lapb/lapb_iface.c:447
 lapb_transmit_buffer+0xce/0x390 net/lapb/lapb_out.c:149
 lapb_send_control+0x1c8/0x320 net/lapb/lapb_subr.c:251
 lapb_establish_data_link+0xeb/0x110 net/lapb/lapb_out.c:163
 lapb_device_event+0x398/0x570 net/lapb/lapb_iface.c:512
 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1994
 call_netdevice_notifiers_extack net/core/dev.c:2032 [inline]
 call_netdevice_notifiers net/core/dev.c:2046 [inline]
 __dev_notify_flags+0x12d/0x2e0 net/core/dev.c:8877
 dev_change_flags+0x10c/0x160 net/core/dev.c:8915
 devinet_ioctl+0x127a/0x1f10 net/ipv4/devinet.c:1177
 inet_ioctl+0x3aa/0x3f0 net/ipv4/af_inet.c:1003
 sock_do_ioctl+0x116/0x280 net/socket.c:1222
 sock_ioctl+0x22e/0x6c0 net/socket.c:1341
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl fs/ioctl.c:893 [inline]
 __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4e4d087d49
Code: 5c c3 48 8d 44 24 08 48 89 54 24 e0 48 89 44 24 c0 48 8d 44 24 d0 48 89 44 24 c8 b8 10 00 00 00 c7 44 24 b8 10 00 00 00 0f 05 <41> 89 c0 3d 00 f0 ff ff 76 10 48 8b 15 ae 60 0d 00 f7 d8 41 83 c8
RSP: 002b:00007ffeb96a1d98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f4e4cfb96c0 RCX: 00007f4e4d087d49
RDX: 00007ffeb96b1f88 RSI: 0000000000008914 RDI: 000000000000001b
RBP: 00007ffeb96c2148 R08: 00007ffeb96b1f48 R09: 00007ffeb96b1ef8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffeb96b1f88 R14: 0000000000000028 R15: 0000000000008914
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:skb_panic+0x157/0x1d0 net/core/skbuff.c:205
Code: b6 04 01 84 c0 74 04 3c 03 7e 21 8b 4b 70 41 56 45 89 e8 48 c7 c7 80 3f 7a 8c 41 57 56 48 89 ee 52 4c 89 e2 e8 0a ee 83 f8 90 <0f> 0b 4c 89 4c 24 10 48 89 54 24 08 48 89 34 24 e8 04 38 02 f9 4c
RSP: 0018:ffffc9000404f668 EFLAGS: 00010286
RAX: 0000000000000086 RBX: ffff88802335c780 RCX: ffffffff816c4a19
RDX: 0000000000000000 RSI: ffffffff816cde56 RDI: 0000000000000005
RBP: ffffffff8c7a52a0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000201 R11: 0000000000000000 R12: ffffffff89fd546a
R13: 0000000000000014 R14: ffff88805209a130 R15: 0000000000000140
FS:  00007f4e4cfb9740(0000) GS:ffff88806a800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000203e9000 CR3: 0000000028878000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/31 08:49 upstream fb24560f31f9 1eda0d14 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream kernel BUG in nr_header
2024/11/21 14:30 net 66418447d27b 4b25d554 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce kernel BUG in nr_header
* Struck through repros no longer work on HEAD.