[PATCH] Revert "ipv4: fix memory leaks in ip_cmsg_send() callers"

From: Yajun Deng
Date: Mon Sep 13 2021 - 00:05:53 EST


This reverts commit 919483096bfe75dda338e98d56da91a263746a0a.

There is only when ip_options_get() return zero need to free.
It already called kfree() when return error.

Fixes: 919483096bfe ("ipv4: fix memory leaks in ip_cmsg_send() callers")
Signed-off-by: Yajun Deng <yajun.deng@xxxxxxxxx>
---
net/ipv4/ip_sockglue.c | 2 +-
net/ipv4/ping.c | 5 ++---
net/ipv4/raw.c | 5 ++---
net/ipv4/udp.c | 5 ++---
4 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index b297bb28556e..7cef9987ab4a 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -279,7 +279,7 @@ int ip_cmsg_send(struct sock *sk, struct msghdr *msg, struct ipcm_cookie *ipc,
case IP_RETOPTS:
err = cmsg->cmsg_len - sizeof(struct cmsghdr);

- /* Our caller is responsible for freeing ipc->opt */
+ /* Our caller is responsible for freeing ipc->opt when err = 0 */
err = ip_options_get(net, &ipc->opt,
KERNEL_SOCKPTR(CMSG_DATA(cmsg)),
err < 40 ? err : 40);
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 1e44a43acfe2..c588f9f2f46c 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -727,10 +727,9 @@ static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)

if (msg->msg_controllen) {
err = ip_cmsg_send(sk, msg, &ipc, false);
- if (unlikely(err)) {
- kfree(ipc.opt);
+ if (unlikely(err))
return err;
- }
+
if (ipc.opt)
free = 1;
}
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index bb446e60cf58..1c98063a3ae8 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -562,10 +562,9 @@ static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)

if (msg->msg_controllen) {
err = ip_cmsg_send(sk, msg, &ipc, false);
- if (unlikely(err)) {
- kfree(ipc.opt);
+ if (unlikely(err))
goto out;
- }
+
if (ipc.opt)
free = 1;
}
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 8851c9463b4b..d5f5981d7a43 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1122,10 +1122,9 @@ int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
if (err > 0)
err = ip_cmsg_send(sk, msg, &ipc,
sk->sk_family == AF_INET6);
- if (unlikely(err < 0)) {
- kfree(ipc.opt);
+ if (unlikely(err < 0))
return err;
- }
+
if (ipc.opt)
free = 1;
connected = 0;
--
2.32.0