Commit de2ea4b6 authored by Jens Axboe's avatar Jens Axboe
Browse files

net: add __sys_accept4_file() helper 



This is identical to __sys_accept4(), except it takes a struct file
instead of an fd, and it also allows passing in extra file->f_flags
flags. The latter is done to support masking in O_NONBLOCK without
manipulating the original file flags.

No functional changes in this patch.

Cc: netdev@vger.kernel.org
Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent fcb323cc

include/linux/socket.h

+3 −0
Original line number Original line Diff line number Diff line
@@ -392,6 +392,9 @@ extern int __sys_recvfrom(int fd, void __user *ubuf, size_t size, 
extern int __sys_sendto(int fd, void __user *buff, size_t len,

extern int __sys_sendto(int fd, void __user *buff, size_t len,

			unsigned int flags, struct sockaddr __user *addr,

			unsigned int flags, struct sockaddr __user *addr,

			int addr_len);

			int addr_len);

extern int __sys_accept4_file(struct file *file, unsigned file_flags,

			struct sockaddr __user *upeer_sockaddr,

			 int __user *upeer_addrlen, int flags);

extern int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr,

extern int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr,

			 int __user *upeer_addrlen, int flags);

			 int __user *upeer_addrlen, int flags);

extern int __sys_socket(int family, int type, int protocol);

extern int __sys_socket(int family, int type, int protocol);

net/socket.c

+41 −24
Original line number Original line Diff line number Diff line
@@ -1690,24 +1690,13 @@ SYSCALL_DEFINE2(listen, int, fd, int, backlog) 
	return __sys_listen(fd, backlog);

	return __sys_listen(fd, backlog);

}

}





/*

int __sys_accept4_file(struct file *file, unsigned file_flags,

 *	For accept, we attempt to create a new socket, set up the link

		       struct sockaddr __user *upeer_sockaddr,

 *	with the client, wake up the client, then return the new

 *	connected fd. We collect the address of the connector in kernel

 *	space and move it to user at the very end. This is unclean because

 *	we open the socket then return an error.

 *

 *	1003.1g adds the ability to recvmsg() to query connection pending

 *	status to recvmsg. We need to add that support in a way thats

 *	clean when we restructure accept also.

 */



int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr,

		       int __user *upeer_addrlen, int flags)

		       int __user *upeer_addrlen, int flags)

{

{

	struct socket *sock, *newsock;

	struct socket *sock, *newsock;

	struct file *newfile;

	struct file *newfile;

	int err, len, newfd, fput_needed;

	int err, len, newfd;

	struct sockaddr_storage address;

	struct sockaddr_storage address;





	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))

	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
@@ -1716,14 +1705,14 @@ int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr, 
	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))

	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))

		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;

		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;





	sock = sockfd_lookup_light(fd, &err, &fput_needed);

	sock = sock_from_file(file, &err);

	if (!sock)

	if (!sock)

		goto out;

		goto out;





	err = -ENFILE;

	err = -ENFILE;

	newsock = sock_alloc();

	newsock = sock_alloc();

	if (!newsock)

	if (!newsock)

		goto out_put;

		goto out;





	newsock->type = sock->type;

	newsock->type = sock->type;

	newsock->ops = sock->ops;

	newsock->ops = sock->ops;
@@ -1738,20 +1727,21 @@ int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr, 
	if (unlikely(newfd < 0)) {

	if (unlikely(newfd < 0)) {

		err = newfd;

		err = newfd;

		sock_release(newsock);

		sock_release(newsock);

		goto out_put;

		goto out;

	}

	}

	newfile = sock_alloc_file(newsock, flags, sock->sk->sk_prot_creator->name);

	newfile = sock_alloc_file(newsock, flags, sock->sk->sk_prot_creator->name);

	if (IS_ERR(newfile)) {

	if (IS_ERR(newfile)) {

		err = PTR_ERR(newfile);

		err = PTR_ERR(newfile);

		put_unused_fd(newfd);

		put_unused_fd(newfd);

		goto out_put;

		goto out;

	}

	}





	err = security_socket_accept(sock, newsock);

	err = security_socket_accept(sock, newsock);

	if (err)

	if (err)

		goto out_fd;

		goto out_fd;





	err = sock->ops->accept(sock, newsock, sock->file->f_flags, false);

	err = sock->ops->accept(sock, newsock, sock->file->f_flags | file_flags,

					false);

	if (err < 0)

	if (err < 0)

		goto out_fd;

		goto out_fd;
@@ -1772,15 +1762,42 @@ int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr, 




	fd_install(newfd, newfile);

	fd_install(newfd, newfile);

	err = newfd;

	err = newfd;



out_put:

	fput_light(sock->file, fput_needed);

out:

out:

	return err;

	return err;

out_fd:

out_fd:

	fput(newfile);

	fput(newfile);

	put_unused_fd(newfd);

	put_unused_fd(newfd);

	goto out_put;

	goto out;



}



/*

 *	For accept, we attempt to create a new socket, set up the link

 *	with the client, wake up the client, then return the new

 *	connected fd. We collect the address of the connector in kernel

 *	space and move it to user at the very end. This is unclean because

 *	we open the socket then return an error.

 *

 *	1003.1g adds the ability to recvmsg() to query connection pending

 *	status to recvmsg. We need to add that support in a way thats

 *	clean when we restructure accept also.

 */



int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr,

		  int __user *upeer_addrlen, int flags)

{

	int ret = -EBADF;

	struct fd f;



	f = fdget(fd);

	if (f.file) {

		ret = __sys_accept4_file(f.file, 0, upeer_sockaddr,

						upeer_addrlen, flags);

		if (f.flags)

			fput(f.file);

	}



	return ret;

}

}





SYSCALL_DEFINE4(accept4, int, fd, struct sockaddr __user *, upeer_sockaddr,

SYSCALL_DEFINE4(accept4, int, fd, struct sockaddr __user *, upeer_sockaddr,

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