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[bpf,sockmap,1/2] bpf, sockmap: fix potential memory leak on unlikely error case

Message ID 20210630215349.73263-2-john.fastabend@gmail.com (mailing list archive)
State Changes Requested
Delegated to: BPF
Headers show
Series potential memleak and proc stats fix | expand

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Commit Message

John Fastabend June 30, 2021, 9:53 p.m. UTC
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@gmail.com>
---
 net/core/skmsg.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/net/core/skmsg.c b/net/core/skmsg.c
index 9b6160a191f8..22603289c2b2 100644
--- a/net/core/skmsg.c
+++ b/net/core/skmsg.c
@@ -505,8 +505,10 @@  static int sk_psock_skb_ingress_enqueue(struct sk_buff *skb,
 	 * drop the skb. We need to linearize the skb so that the mapping
 	 * in skb_to_sgvec can not error.
 	 */
-	if (skb_linearize(skb))
+	if (skb_linearize(skb)) {
+		kfree(msg);
 		return -EAGAIN;
+	}
 	num_sge = skb_to_sgvec(skb, msg->sg.data, 0, skb->len);
 	if (unlikely(num_sge < 0)) {
 		kfree(msg);