Commit 17240749 authored by Antonio Quartulli's avatar Antonio Quartulli Committed by Paolo Abeni
Browse files

skb: implement skb_send_sock_locked_with_flags() 



When sending an skb over a socket using skb_send_sock_locked(),
it is currently not possible to specify any flag to be set in
msghdr->msg_flags.

However, we may want to pass flags the user may have specified,
like MSG_NOSIGNAL.

Extend __skb_send_sock() with a new argument 'flags' and add a
new interface named skb_send_sock_locked_with_flags().

Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <horms@kernel.org>
Signed-off-by: default avatarAntonio Quartulli <antonio@openvpn.net>
Link: https://patch.msgid.link/20250415-b4-ovpn-v26-12-577f6097b964@openvpn.net


Reviewed-by: default avatarSabrina Dubroca <sd@queasysnail.net>
Tested-by: default avatarOleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 11851cbd

include/linux/skbuff.h

+2 −0
Original line number Diff line number Diff line
@@ -4145,6 +4145,8 @@ int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset, 
		    unsigned int flags);

int skb_send_sock_locked(struct sock *sk, struct sk_buff *skb, int offset,

			 int len);

int skb_send_sock_locked_with_flags(struct sock *sk, struct sk_buff *skb,

				    int offset, int len, int flags);

int skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset, int len);

void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to);

unsigned int skb_zerocopy_headlen(const struct sk_buff *from);

net/core/skbuff.c

+13 −5
Original line number Diff line number Diff line
@@ -3227,7 +3227,7 @@ static int sendmsg_unlocked(struct sock *sk, struct msghdr *msg) 


typedef int (*sendmsg_func)(struct sock *sk, struct msghdr *msg);

static int __skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset,

			   int len, sendmsg_func sendmsg)

			   int len, sendmsg_func sendmsg, int flags)

{

	unsigned int orig_len = len;

	struct sk_buff *head = skb;
@@ -3245,7 +3245,7 @@ static int __skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset, 
		kv.iov_base = skb->data + offset;

		kv.iov_len = slen;

		memset(&msg, 0, sizeof(msg));

		msg.msg_flags = MSG_DONTWAIT;

		msg.msg_flags = MSG_DONTWAIT | flags;



		iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &kv, 1, slen);

		ret = INDIRECT_CALL_2(sendmsg, sendmsg_locked,
@@ -3282,7 +3282,8 @@ static int __skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset, 
		while (slen) {

			struct bio_vec bvec;

			struct msghdr msg = {

				.msg_flags = MSG_SPLICE_PAGES | MSG_DONTWAIT,

				.msg_flags = MSG_SPLICE_PAGES | MSG_DONTWAIT |

					     flags,

			};



			bvec_set_page(&bvec, skb_frag_page(frag), slen,
@@ -3328,14 +3329,21 @@ static int __skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset, 
int skb_send_sock_locked(struct sock *sk, struct sk_buff *skb, int offset,

			 int len)

{

	return __skb_send_sock(sk, skb, offset, len, sendmsg_locked);

	return __skb_send_sock(sk, skb, offset, len, sendmsg_locked, 0);

}

EXPORT_SYMBOL_GPL(skb_send_sock_locked);



int skb_send_sock_locked_with_flags(struct sock *sk, struct sk_buff *skb,

				    int offset, int len, int flags)

{

	return __skb_send_sock(sk, skb, offset, len, sendmsg_locked, flags);

}

EXPORT_SYMBOL_GPL(skb_send_sock_locked_with_flags);



/* Send skb data on a socket. Socket must be unlocked. */

int skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset, int len)

{

	return __skb_send_sock(sk, skb, offset, len, sendmsg_unlocked);

	return __skb_send_sock(sk, skb, offset, len, sendmsg_unlocked, 0);

}



/**