if user sets nonexistent xdp_flags to detach xdp prog, kernel should
return err and tell user that detach failed with detail info.
Signed-off-by: Zhengchao Shao <shaozhengchao@xxxxxxxxxx>
---
net/core/dev.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/net/core/dev.c b/net/core/dev.c
index 8ed0272bf32f..8ed05ef62c68 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -9149,6 +9149,12 @@ static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack
return -EBUSY;
}
+ /* no BPF XDP prog attached */
+ if (!new_prog && !(dev->xdp_state[mode].prog)) {
+ NL_SET_ERR_MSG(extack, "no BPF XDP prog attached");
+ return -ENOENT;
+ }
+
/* don't allow if an upper device already has a program */
netdev_for_each_upper_dev_rcu(dev, upper, iter) {
if (dev_xdp_prog_count(upper) > 0) {
--
2.17.1
