[syzbot] [bpf?] WARNING in dev_xdp_install

syzbot
2025-03-28T14:36:25Z

Hello,

syzbot found the following issue on:

HEAD commit: 1a9239bb4253 Merge tag 'net-next-6.15' of git://git.kernel..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17989bb0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=d48017cf0c2458bf
dashboard link: https://syzkaller.appspot.com/bug?extid=08936936fe8132f91f1a
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0795c9a2c8ce/disk-1a9239bb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/dfe4e652ed32/vmlinux-1a9239bb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/34deb7756b26/bzImage-1a9239bb.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+08936936fe8132f91f1a@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 8456 at ./include/net/netdev_lock.h:54 netdev_ops_assert_locked include/net/netdev_lock.h:54 [inline]
WARNING: CPU: 1 PID: 8456 at ./include/net/netdev_lock.h:54 dev_xdp_install+0x610/0x9b0 net/core/dev.c:9911
Modules linked in:
CPU: 1 UID: 0 PID: 8456 Comm: syz.5.847 Not tainted 6.14.0-syzkaller-05877-g1a9239bb4253 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:netdev_ops_assert_locked include/net/netdev_lock.h:54 [inline]
RIP: 0010:dev_xdp_install+0x610/0x9b0 net/core/dev.c:9911
Code: 8d bc 24 28 0d 00 00 be ff ff ff ff e8 69 c5 26 02 31 ff 89 c5 89 c6 e8 0e af 81 f8 85 ed 0f 85 59 fb ff ff e8 d1 b3 81 f8 90 <0f> 0b 90 e9 4b fb ff ff e8 c3 b3 81 f8 49 8d bc 24 28 0d 00 00 be
RSP: 0018:ffffc9001f13f950 EFLAGS: 00010287
RAX: 000000000000023c RBX: ffff888059e8ccbd RCX: ffffc9000da1b000
RDX: 0000000000080000 RSI: ffffffff89395ebf RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888059e8c000
R13: ffffffff870484d0 R14: ffffc9000ec3f000 R15: 0000000000000001
FS: 00007f6e99bf66c0(0000) GS:ffff888124b41000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2f3eb0 CR3: 000000007f4ec000 CR4: 0000000000350ef0
Call Trace:
<TASK>
dev_xdp_attach+0x6d1/0x16a0 net/core/dev.c:10094
dev_xdp_attach_link net/core/dev.c:10113 [inline]
bpf_xdp_link_attach+0x2c5/0x680 net/core/dev.c:10287
link_create kernel/bpf/syscall.c:5379 [inline]
__sys_bpf+0x1bc7/0x4c80 kernel/bpf/syscall.c:5865
__do_sys_bpf kernel/bpf/syscall.c:5902 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5900 [inline]
__x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:5900
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6e9bd8d169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6e99bf6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f6e9bfa5fa0 RCX: 00007f6e9bd8d169
RDX: 0000000000000040 RSI: 0000200000000000 RDI: 000000000000001c
RBP: 00007f6e9be0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f6e9bfa5fa0 R15: 00007fff0d50ed58
</TASK>

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