ipv4: fix memory leaks in ip_cmsg_send() callers

[ Upstream commit 919483096bfe75dda338e98d56da91a263746a0a ]

Dmitry reported memory leaks of IP options allocated in
ip_cmsg_send() when/if this function returns an error.

Callers are responsible for the freeing.

Many thanks to Dmitry for the report and diagnostic.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index f6603142cb33c7c2e211414c4f193835297f9fe5..9e4f832aaf1369d5a436c8530b77de4e2774d410 100644 (file)
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -200,6 +200,8 @@ int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc)
                switch (cmsg->cmsg_type) {
                case IP_RETOPTS:
                        err = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
+
+                       /* Our caller is responsible for freeing ipc->opt */
                        err = ip_options_get(net, &ipc->opt, CMSG_DATA(cmsg),
                                             err < 40 ? err : 40);
                        if (err)

diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 54012b8c0ef93163a105119a4d06ea446a53707e..716dff49d0b9eb8f64d267aa024d4f431e71fd8b 100644 (file)
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -740,8 +740,10 @@ int ping_v4_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 
        if (msg->msg_controllen) {
                err = ip_cmsg_send(sock_net(sk), msg, &ipc);
-               if (err)
+               if (unlikely(err)) {
+                       kfree(ipc.opt);
                        return err;
+               }
                if (ipc.opt)
                        free = 1;
        }

diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 6183d36c038b766260c45cc0647604a1e1f52b5d..ed96b2320e5f18043d60a6b906693a1df106e2a9 100644 (file)
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -523,8 +523,10 @@ static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 
        if (msg->msg_controllen) {
                err = ip_cmsg_send(sock_net(sk), msg, &ipc);
-               if (err)
+               if (unlikely(err)) {
+                       kfree(ipc.opt);
                        goto out;
+               }
                if (ipc.opt)
                        free = 1;
        }

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index f8e3046671081d0d8bf4b5d872c9b33822ddb175..f904b644a40ce2b57a1ec83bcdc0e26eedb355e6 100644 (file)
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -910,8 +910,10 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 
        if (msg->msg_controllen) {
                err = ip_cmsg_send(sock_net(sk), msg, &ipc);
-               if (err)
+               if (unlikely(err)) {
+                       kfree(ipc.opt);
                        return err;
+               }
                if (ipc.opt)
                        free = 1;
                connected = 0;