[v5.15] BUG: unable to handle kernel NULL pointer dereference in bond_xdp_xmit (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: dc027a595035 Linux 5.15.209
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14b7c72e580000
kernel config: https://syzkaller.appspot.com/x/.config?x=353ae28c40b35af5
dashboard link: https://syzkaller.appspot.com/bug?extid=3f41c3a4b0faf5294982
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/586ac2a2fd9d/disk-dc027a59.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/06dcb6a2fcd3/vmlinux-dc027a59.xz
kernel image: https://storage.googleapis.com/syzbot-assets/567131e0cbcc/bzImage-dc027a59.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3f41c3...@syzkaller.appspotmail.com

BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 759e1067 P4D 759e1067 PUD 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 5856 Comm: syz.1.430 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0018:ffffc90002d5f618 EFLAGS: 00010246
RAX: 1ffffffff1559c8c RBX: 0000000000000000 RCX: 0000000000000001
RDX: ffffc90002d5f6c0 RSI: 0000000000000001 RDI: ffff888078d28000
RBP: ffffc90002d5f730 R08: ffff888078d2803f R09: 1ffff1100f1a5007
R10: dffffc0000000000 R11: ffffed100f1a5008 R12: ffffffff8aace460
R13: dffffc0000000000 R14: ffff888078d28000 R15: ffffe8ffffc46f00
FS: 00007f8e5c79f6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 000000007451f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
bond_xdp_xmit+0x288/0x440 drivers/net/bonding/bond_main.c:5244
bq_xmit_all+0xc25/0x1000 kernel/bpf/devmap.c:391
__dev_flush+0xbf/0x1b0 kernel/bpf/devmap.c:421
xdp_do_flush+0xa/0x20 net/core/filter.c:4002
tun_build_skb drivers/net/tun.c:1703 [inline]
tun_get_user+0x2ad2/0x3a70 drivers/net/tun.c:1797
tun_chr_write_iter+0x112/0x1e0 drivers/net/tun.c:2019
call_write_iter include/linux/fs.h:2173 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x745/0xd60 fs/read_write.c:594
ksys_write+0x152/0x260 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8e5e50668e
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:00007f8e5c79efb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8e5c79f6c0 RCX: 00007f8e5e50668e
RDX: 0000000000000032 RSI: 0000200000000000 RDI: 00000000000000c8
RBP: 00007f8e5e5dbd6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8e5e7bf038 R14: 00007f8e5e7befa0 R15: 00007ffebec36608
</TASK>
Modules linked in:
CR2: 0000000000000000
---[ end trace 38c275376461f097 ]---
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0018:ffffc90002d5f618 EFLAGS: 00010246
RAX: 1ffffffff1559c8c RBX: 0000000000000000 RCX: 0000000000000001
RDX: ffffc90002d5f6c0 RSI: 0000000000000001 RDI: ffff888078d28000
RBP: ffffc90002d5f730 R08: ffff888078d2803f R09: 1ffff1100f1a5007
R10: dffffc0000000000 R11: ffffed100f1a5008 R12: ffffffff8aace460
R13: dffffc0000000000 R14: ffff888078d28000 R15: ffffe8ffffc46f00
FS: 00007f8e5c79f6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 000000007451f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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