If skb_linearize is needed and fails we could leak a msg on the error
handling. To fix ensure we kfree the msg block before returning error.
Found during code review.
Fixes: 4363023d2668e ("bpf, sockmap: Avoid failures from skb_to_sgvec when skb has frag_list")
Signed-off-by: John Fastabend <john.fastabend@xxxxxxxxx>
---
net/core/skmsg.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/net/core/skmsg.c b/net/core/skmsg.c
index 9b6160a191f8..1a9059e5b3b3 100644
--- a/net/core/skmsg.c
+++ b/net/core/skmsg.c
@@ -508,10 +508,8 @@ static int sk_psock_skb_ingress_enqueue(struct sk_buff *skb,
if (skb_linearize(skb))
return -EAGAIN;
num_sge = skb_to_sgvec(skb, msg->sg.data, 0, skb->len);
- if (unlikely(num_sge < 0)) {
- kfree(msg);
+ if (unlikely(num_sge < 0))
return num_sge;
- }
copied = skb->len;
msg->sg.start = 0;
@@ -530,6 +528,7 @@ static int sk_psock_skb_ingress(struct sk_psock *psock, struct sk_buff *skb)
{
struct sock *sk = psock->sk;
struct sk_msg *msg;
+ int err;
/* If we are receiving on the same sock skb->sk is already assigned,
* skip memory accounting and owner transition seeing it already set
@@ -548,7 +547,10 @@ static int sk_psock_skb_ingress(struct sk_psock *psock, struct sk_buff *skb)
* into user buffers.
*/
skb_set_owner_r(skb, sk);
- return sk_psock_skb_ingress_enqueue(skb, psock, sk, msg);
+ err = sk_psock_skb_ingress_enqueue(skb, psock, sk, msg);
+ if (err < 0)
+ kfree(msg);
+ return err;
}
/* Puts an skb on the ingress queue of the socket already assigned to the
--
2.25.1
