bpf: add missing ops lock around dev_xdp_attach_link

Syzkaller points out that create_link path doesn't grab ops lock,
add it.

Reported-by: syzbot+08936936fe8132f91f1a@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/67e6b3e8.050a0220.2f068f.0079.GAE@google.com/
Fixes: 97246d6d21c2 ("net: hold netdev instance lock during ndo_bpf")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250331142814.1887506-1-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/core/dev.c b/net/core/dev.c
index be17e0660144fc8fa8927760d85c0a6b322e1e94..5d20ff226d5e78a4e203bce7ad61db83c79675f7 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -10284,7 +10284,9 @@ int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
                goto unlock;
        }
 
+       netdev_lock_ops(dev);
        err = dev_xdp_attach_link(dev, &extack, link);
+       netdev_unlock_ops(dev);
        rtnl_unlock();
 
        if (err) {