[PATCH net] ipv4: fix memory leaks in ip_cmsg_send() callers
From: Eric Dumazet <hidden>
Date: 2016-02-04 14:23:30
Subsystem:
networking [general], networking [ipv4/ipv6], the rest, user datagram protocol (udp) · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds, Willem de Bruijn
From: Eric Dumazet <edumazet@google.com> 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> --- net/ipv4/ip_sockglue.c | 2 ++ net/ipv4/ping.c | 4 +++- net/ipv4/raw.c | 4 +++- net/ipv4/udp.c | 4 +++- 4 files changed, 11 insertions(+), 3 deletions(-)
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 5f73a7c03e27..a50124260f5a 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c@@ -249,6 +249,8 @@ 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 c117b21b937d..ec74b1a34315 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c@@ -746,8 +746,10 @@ static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) if (msg->msg_controllen) { err = ip_cmsg_send(sock_net(sk), msg, &ipc, false); - 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 bc35f1842512..bba4f6f379a9 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c@@ -547,8 +547,10 @@ static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) if (msg->msg_controllen) { err = ip_cmsg_send(net, msg, &ipc, false); - 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 be0b21852b13..8182363bff5e 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c@@ -1048,8 +1048,10 @@ int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) if (msg->msg_controllen) { err = ip_cmsg_send(sock_net(sk), msg, &ipc, sk->sk_family == AF_INET6); - if (err) + if (unlikely(err)) { + kfree(ipc.opt); return err; + } if (ipc.opt) free = 1; connected = 0;