1 From 442f5963a52060fcf86a73377c31a863738632dd Mon Sep 17 00:00:00 2001
2 From: Wei Xu <wexu@redhat.com>
3 Date: Fri, 1 Dec 2017 05:10:37 -0500
4 Subject: [PATCH 009/241] tun: free skb in early errors
6 Content-Type: text/plain; charset=UTF-8
7 Content-Transfer-Encoding: 8bit
9 tun_recvmsg() supports accepting skb by msg_control after
10 commit ac77cfd4258f ("tun: support receiving skb through msg_control"),
11 the skb if presented should be freed no matter how far it can go
12 along, otherwise it would be leaked.
14 This patch fixes several missed cases.
16 Signed-off-by: Wei Xu <wexu@redhat.com>
17 Reported-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com>
18 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
20 drivers/net/tun.c | 24 ++++++++++++++++++------
21 1 file changed, 18 insertions(+), 6 deletions(-)
23 diff --git a/drivers/net/tun.c b/drivers/net/tun.c
24 index cb1f7747adad..5143e948d7d1 100644
25 --- a/drivers/net/tun.c
26 +++ b/drivers/net/tun.c
27 @@ -1519,8 +1519,11 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile,
29 tun_debug(KERN_INFO, tun, "tun_do_read\n");
31 - if (!iov_iter_count(to))
32 + if (!iov_iter_count(to)) {
39 /* Read frames from ring */
40 @@ -1636,22 +1639,24 @@ static int tun_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len,
42 struct tun_file *tfile = container_of(sock, struct tun_file, socket);
43 struct tun_struct *tun = __tun_get(tfile);
44 + struct sk_buff *skb = m->msg_control;
54 if (flags & ~(MSG_DONTWAIT|MSG_TRUNC|MSG_ERRQUEUE)) {
59 if (flags & MSG_ERRQUEUE) {
60 ret = sock_recv_errqueue(sock->sk, m, total_len,
61 SOL_PACKET, TUN_TX_TIMESTAMP);
64 - ret = tun_do_read(tun, tfile, &m->msg_iter, flags & MSG_DONTWAIT,
66 + ret = tun_do_read(tun, tfile, &m->msg_iter, flags & MSG_DONTWAIT, skb);
67 if (ret > (ssize_t)total_len) {
68 m->msg_flags |= MSG_TRUNC;
69 ret = flags & MSG_TRUNC ? ret : total_len;
70 @@ -1659,6 +1664,13 @@ static int tun_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len,
83 static int tun_peek_len(struct socket *sock)