Commit 483cec55 authored Feb 28, 2025 by Geliang Tang Committed by Jakub Kicinski Mar 03, 2025

net: use sock_kmemdup for ip_options

Instead of using sock_kmalloc() to allocate an ip_options and then
immediately duplicate another ip_options to the newly allocated one in
ipv6_dup_options(), mptcp_copy_ip_options() and sctp_v4_copy_ip_options(),
the newly added sock_kmemdup() helper can be used to simplify the code.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/91ae749d66600ec6fb679e0e518fda6acb5c3e6f.1740735165.git.tanggeliang@kylinos.cn

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

parent 456cc675

net/ipv6/exthdrs.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -1204,10 +1204,9 @@ ipv6_dup_options(struct sock sk, struct ipv6_txoptions opt)
		{
		struct ipv6_txoptions *opt2;

		opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC);
		opt2 = sock_kmemdup(sk, opt, opt->tot_len, GFP_ATOMIC);
		if (opt2) {
		long dif = (char )opt2 - (char )opt;
		memcpy(opt2, opt, opt->tot_len);
		if (opt2->hopopt)
		((char *)&opt2->hopopt) += dif;
		if (opt2->dst0opt)

net/mptcp/protocol.c

+2 −5

Original line number	Diff line number	Diff line
		@@ -3178,12 +3178,9 @@ static void mptcp_copy_ip_options(struct sock newsk, const struct sock sk)
		rcu_read_lock();
		inet_opt = rcu_dereference(inet->inet_opt);
		if (inet_opt) {
		newopt = sock_kmalloc(newsk, sizeof(*inet_opt) +
		newopt = sock_kmemdup(newsk, inet_opt, sizeof(*inet_opt) +
		inet_opt->opt.optlen, GFP_ATOMIC);
		if (newopt)
		memcpy(newopt, inet_opt, sizeof(*inet_opt) +
		inet_opt->opt.optlen);
		else
		if (!newopt)
		net_warn_ratelimited("%s: Failed to copy ip options\n", __func__);
		}
		RCU_INIT_POINTER(newinet->inet_opt, newopt);

net/sctp/protocol.c

+2 −5

Original line number	Diff line number	Diff line
		@@ -185,12 +185,9 @@ static void sctp_v4_copy_ip_options(struct sock sk, struct sock newsk)
		rcu_read_lock();
		inet_opt = rcu_dereference(inet->inet_opt);
		if (inet_opt) {
		newopt = sock_kmalloc(newsk, sizeof(*inet_opt) +
		newopt = sock_kmemdup(newsk, inet_opt, sizeof(*inet_opt) +
		inet_opt->opt.optlen, GFP_ATOMIC);
		if (newopt)
		memcpy(newopt, inet_opt, sizeof(*inet_opt) +
		inet_opt->opt.optlen);
		else
		if (!newopt)
		pr_err("%s: Failed to copy ip options\n", __func__);
		}
		RCU_INIT_POINTER(newinet->inet_opt, newopt);