[PATCH 3/3] tap: free skb if flags error
From: <hidden>
Date: 2017-12-01 10:10:38
Subsystem:
networking drivers, the rest, tun/tap driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Willem de Bruijn, Jason Wang
Possibly related (same subject, not in this thread)
- 2017-12-01 · Re: [PATCH 3/3] tap: free skb if flags error · "Michael S. Tsirkin" <mst@redhat.com>
- 2017-12-01 · Re: [PATCH 3/3] tap: free skb if flags error · Jason Wang <hidden>
- 2017-12-01 · [PATCH 3/3] tap: free skb if flags error · <hidden>
From: Wei Xu <redacted>
tap_recvmsg() supports accepting skb by msg_control after
commit 3b4ba04acca8 ("tap: support receiving skb from msg_control"),
the skb if presented should be freed within the function, otherwise
it would be leaked.
Signed-off-by: Wei Xu <redacted>
Reported-by: Matthew Rosato <redacted>
---
drivers/net/tap.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/drivers/net/tap.c b/drivers/net/tap.c
index e9489b8..0a886fda 100644
--- a/drivers/net/tap.c
+++ b/drivers/net/tap.c@@ -829,8 +829,11 @@ static ssize_t tap_do_read(struct tap_queue *q, DEFINE_WAIT(wait); ssize_t ret = 0; - if (!iov_iter_count(to)) + if (!iov_iter_count(to)) { + if (skb) + kfree_skb(skb); return 0; + } if (skb) goto put;
@@ -1154,11 +1157,14 @@ static int tap_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len, int flags) { struct tap_queue *q = container_of(sock, struct tap_queue, sock); + struct sk_buff *skb = m->msg_control; int ret; - if (flags & ~(MSG_DONTWAIT|MSG_TRUNC)) + if (flags & ~(MSG_DONTWAIT|MSG_TRUNC)) { + if (skb) + kfree_skb(skb); return -EINVAL; - ret = tap_do_read(q, &m->msg_iter, flags & MSG_DONTWAIT, - m->msg_control); + } + ret = tap_do_read(q, &m->msg_iter, flags & MSG_DONTWAIT, skb); if (ret > total_len) { m->msg_flags |= MSG_TRUNC; ret = flags & MSG_TRUNC ? ret : total_len;
--
1.8.3.1