Commit a18b2d1c authored by Eric Dumazet's avatar Eric Dumazet Committed by Geliang Tang
Browse files

inet: lockless getsockopt(IP_MTU) 

mainline inclusion
from mainline-v6.7-rc1
commit 3523bc91e4b4da39ccf18a0252d13108877ece0a
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I9VYQ9
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=3523bc91e4b4da39ccf18a0252d13108877ece0a



--------------------------------

sk_dst_get() does not require socket lock.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Reviewed-by: default avatarJackie Liu <liuyun01@kylinos.cn>
Signed-off-by: default avatarGeliang Tang <tanggeliang@kylinos.cn>
parent dbd9755a

net/ipv4/ip_sockglue.c

+9 −11
Original line number Diff line number Diff line
@@ -1629,13 +1629,6 @@ int do_ip_getsockopt(struct sock *sk, int level, int optname, 
			return -EFAULT;

		return 0;

	}

	}



	if (needs_rtnl)

		rtnl_lock();

	sockopt_lock_sock(sk);



	switch (optname) {

	case IP_MTU:

	{

		struct dst_entry *dst;
@@ -1645,12 +1638,17 @@ int do_ip_getsockopt(struct sock *sk, int level, int optname, 
			val = dst_mtu(dst);

			dst_release(dst);

		}

		if (!val) {

			sockopt_release_sock(sk);

		if (!val)

			return -ENOTCONN;

		goto copyval;

	}

		break;

	}



	if (needs_rtnl)

		rtnl_lock();

	sockopt_lock_sock(sk);



	switch (optname) {

	case IP_UNICAST_IF:

		val = (__force int)htonl((__u32) inet->uc_index);

		break;