[v6.1] WARNING in __dev_queue_xmit (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e4f7d8be268e Linux 6.1.182
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15857e49580000
kernel config: https://syzkaller.appspot.com/x/.config?x=872c04466179833f
dashboard link: https://syzkaller.appspot.com/bug?extid=e1c4510f831b4711ffae
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7cd9b1875376/disk-e4f7d8be.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4b5d35d18c31/vmlinux-e4f7d8be.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d5ee64c2af77/Image-e4f7d8be.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e1c451...@syzkaller.appspotmail.com

------------[ cut here ]------------
skb_assert_len
WARNING: CPU: 1 PID: 6992 at include/linux/skbuff.h:2570 skb_assert_len include/linux/skbuff.h:2570 [inline]
WARNING: CPU: 1 PID: 6992 at include/linux/skbuff.h:2570 __dev_queue_xmit+0x19f0/0x3154 net/core/dev.c:4286
Modules linked in:
CPU: 1 PID: 6992 Comm: syz.5.747 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : skb_assert_len include/linux/skbuff.h:2570 [inline]
pc : __dev_queue_xmit+0x19f0/0x3154 net/core/dev.c:4286
lr : skb_assert_len include/linux/skbuff.h:2570 [inline]
lr : __dev_queue_xmit+0x19f0/0x3154 net/core/dev.c:4286
sp : ffff800021bc75c0
x29: ffff800021bc7780 x28: ffff700004378ec8 x27: dfff800000000000
x26: 1fffe0001a48ae1a x25: ffff0000c9bdc000 x24: ffff0000dd7fc664
x23: 1fffe0001a48ae02 x22: 0000000000000000 x21: ffff0000d2457010
x20: ffff800017d5e000 x19: ffff0000d2457000 x18: 1fffe00033e7697e
x17: ffff80001537d000 x16: ffff8000082dd248 x15: 0000000040000000
x14: 0000000000000001 x13: 1fffe00033e79070 x12: 0000000000000000
x11: ff0080000a975d20 x10: 0000000000000003 x9 : 6760709c07014d00
x8 : 6760709c07014d00 x7 : ffff80000825ab50 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000
x2 : 0000000000000006 x1 : ffff800011cedc80 x0 : ffff80018a0de000
Call trace:
skb_assert_len include/linux/skbuff.h:2570 [inline]
__dev_queue_xmit+0x19f0/0x3154 net/core/dev.c:4286
dev_queue_xmit+0x24/0x34 include/linux/netdevice.h:3051
tpacket_snd net/packet/af_packet.c:2936 [inline]
packet_sendmsg+0x1b14/0x40ac net/packet/af_packet.c:3162
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
__sys_sendto+0x324/0x440 net/socket.c:2153
__do_sys_sendto net/socket.c:2165 [inline]
__se_sys_sendto net/socket.c:2161 [inline]
__arm64_sys_sendto+0xe4/0x104 net/socket.c:2161
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 1302
hardirqs last enabled at (1301): [<ffff80000825abe4>] raw_spin_rq_unlock_irq kernel/sched/sched.h:1374 [inline]
hardirqs last enabled at (1301): [<ffff80000825abe4>] finish_lock_switch+0xb0/0x1c8 kernel/sched/core.c:5005
hardirqs last disabled at (1302): [<ffff800011b8c2bc>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last enabled at (1272): [<ffff800008031254>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (1270): [<ffff800008031220>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---
skb len=0 headroom=144 headlen=0 tailroom=560
mac=(144,0) net=(144,-1) trans=-1
shinfo(txflags=0 nr_frags=0 gso(size=0 type=0 segs=0))
csum(0x0 ip_summed=0 complete_sw=0 valid=0 level=0)
hash(0x0 sw=0 l4=0) proto=0x0010 pkttype=0 iif=0
dev name=wg0 feat=0x00000106401d5829
sk family=17 type=2 proto=0


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: e4f7d8be268e Linux 6.1.182
git tree: linux-6.1.y

console output: https://syzkaller.appspot.com/x/log.txt?x=160d7e49580000

kernel config: https://syzkaller.appspot.com/x/.config?x=872c04466179833f
dashboard link: https://syzkaller.appspot.com/bug?extid=e1c4510f831b4711ffae
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
userspace arch: arm64

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=110d7e49580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=172cafb9580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7cd9b1875376/disk-e4f7d8be.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4b5d35d18c31/vmlinux-e4f7d8be.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d5ee64c2af77/Image-e4f7d8be.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e1c451...@syzkaller.appspotmail.com

------------[ cut here ]------------
skb_assert_len

WARNING: CPU: 1 PID: 4540 at include/linux/skbuff.h:2570 skb_assert_len include/linux/skbuff.h:2570 [inline]
WARNING: CPU: 1 PID: 4540 at include/linux/skbuff.h:2570 __dev_queue_xmit+0x19f0/0x3154 net/core/dev.c:4286
Modules linked in:
CPU: 1 PID: 4540 Comm: syz.0.17 Not tainted syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : skb_assert_len include/linux/skbuff.h:2570 [inline]
pc : __dev_queue_xmit+0x19f0/0x3154 net/core/dev.c:4286
lr : skb_assert_len include/linux/skbuff.h:2570 [inline]
lr : __dev_queue_xmit+0x19f0/0x3154 net/core/dev.c:4286

sp : ffff8000211275c0
x29: ffff800021127780 x28: ffff700004224ec8 x27: dfff800000000000
x26: 1fffe00018ea4382 x25: ffff0000ef478000 x24: ffff0000d3604664
x23: 1fffe00018ea436a x22: 0000000000000000 x21: ffff0000c7521b50
x20: ffff800017d5e000 x19: ffff0000c7521b40 x18: 0000000000000000
x17: 0000000000000000 x16: ffff800011b90080 x15: 0000000000000000
x14: 0000000000000001 x13: 1fffe00033e769a3 x12: 0000000000000000
x11: ff00800008195f70 x10: 0000000000000000 x9 : 9647628cdd211400
x8 : 9647628cdd211400 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800021127058 x4 : ffff800015464e80 x3 : ffff800008540904
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000000

Call trace:
skb_assert_len include/linux/skbuff.h:2570 [inline]
__dev_queue_xmit+0x19f0/0x3154 net/core/dev.c:4286
dev_queue_xmit+0x24/0x34 include/linux/netdevice.h:3051
tpacket_snd net/packet/af_packet.c:2936 [inline]
packet_sendmsg+0x1b14/0x40ac net/packet/af_packet.c:3162
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
__sys_sendto+0x324/0x440 net/socket.c:2153
__do_sys_sendto net/socket.c:2165 [inline]
__se_sys_sendto net/socket.c:2161 [inline]
__arm64_sys_sendto+0xe4/0x104 net/socket.c:2161
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

irq event stamp: 2572
hardirqs last enabled at (2571): [<ffff80000831388c>] __up_console_sem+0xb4/0xfc kernel/printk/printk.c:261
hardirqs last disabled at (2572): [<ffff800011b8c2bc>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last enabled at (2536): [<ffff800008031254>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (2534): [<ffff800008031220>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19

---[ end trace 0000000000000000 ]---
skb len=0 headroom=144 headlen=0 tailroom=560
mac=(144,0) net=(144,-1) trans=-1
shinfo(txflags=0 nr_frags=0 gso(size=0 type=0 segs=0))
csum(0x0 ip_summed=0 complete_sw=0 valid=0 level=0)
hash(0x0 sw=0 l4=0) proto=0x0010 pkttype=0 iif=0
dev name=wg0 feat=0x00000106401d5829
sk family=17 type=2 proto=0


---

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