net: rtnetlink: fix module reference count leak issue in rtnetlink_rcv_msg

commit 5b22f62724a0a09e00d301abf5b57b0c12be8a16 upstream.

When bulk delete command is received in the rtnetlink_rcv_msg function,
if bulk delete is not supported, module_put is not called to release
the reference counting. As a result, module reference count is leaked.

Fixes: a6cec0bcd342 ("net: rtnetlink: add bulk delete support flag")
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20220815024629.240367-1-shaozhengchao@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 0b44c6b1ef999cb1673fb8eb630b0855863c0bac..99337557408b506b0a3083e8e01085365bda74c2 100644 (file)
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -5624,6 +5624,7 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
        if (kind == RTNL_KIND_DEL && (nlh->nlmsg_flags & NLM_F_BULK) &&
            !(flags & RTNL_FLAG_BULK_DEL_SUPPORTED)) {
                NL_SET_ERR_MSG(extack, "Bulk delete is not supported");
+               module_put(owner);
                goto err_unlock;
        }