Commit 2618d530 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by David S. Miller
Browse files

net/scm: cleanup scm_detach_fds 



Factor out two helpes to keep the code tidy.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 0462b6bd

net/core/scm.c

+51 −43
Original line number Diff line number Diff line
@@ -277,59 +277,66 @@ void put_cmsg_scm_timestamping(struct msghdr *msg, struct scm_timestamping_inter 
}

EXPORT_SYMBOL(put_cmsg_scm_timestamping);



void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm)

static int __scm_install_fd(struct file *file, int __user *ufd, int o_flags)

{

	struct cmsghdr __user *cm

		= (__force struct cmsghdr __user*)msg->msg_control;



	int fdmax = 0;

	int fdnum = scm->fp->count;

	struct file **fp = scm->fp->fp;

	int __user *cmfptr;

	int err = 0, i;



	if (MSG_CMSG_COMPAT & msg->msg_flags) {

		scm_detach_fds_compat(msg, scm);

		return;

	}

	struct socket *sock;

	int new_fd;

	int error;



	if (msg->msg_controllen > sizeof(struct cmsghdr))

		fdmax = ((msg->msg_controllen - sizeof(struct cmsghdr))

			 / sizeof(int));

	error = security_file_receive(file);

	if (error)

		return error;



	if (fdnum < fdmax)

		fdmax = fdnum;

	new_fd = get_unused_fd_flags(o_flags);

	if (new_fd < 0)

		return new_fd;



	for (i=0, cmfptr =(int __user *)CMSG_USER_DATA(cm); i<fdmax;

	     i++, cmfptr++)

	{

		struct socket *sock;

		int new_fd;

		err = security_file_receive(fp[i]);

		if (err)

			break;

		err = get_unused_fd_flags(MSG_CMSG_CLOEXEC & msg->msg_flags

					  ? O_CLOEXEC : 0);

		if (err < 0)

			break;

		new_fd = err;

		err = put_user(new_fd, cmfptr);

		if (err) {

	error = put_user(new_fd, ufd);

	if (error) {

		put_unused_fd(new_fd);

			break;

		return error;

	}



	/* Bump the usage count and install the file. */

		sock = sock_from_file(fp[i], &err);

	sock = sock_from_file(file, &error);

	if (sock) {

		sock_update_netprioidx(&sock->sk->sk_cgrp_data);

		sock_update_classid(&sock->sk->sk_cgrp_data);

	}

		fd_install(new_fd, get_file(fp[i]));

	fd_install(new_fd, get_file(file));

	return error;

}



	if (i > 0)

static int scm_max_fds(struct msghdr *msg)

{

	if (msg->msg_controllen <= sizeof(struct cmsghdr))

		return 0;

	return (msg->msg_controllen - sizeof(struct cmsghdr)) / sizeof(int);

}



void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm)

{

	struct cmsghdr __user *cm

		= (__force struct cmsghdr __user*)msg->msg_control;

	int o_flags = (msg->msg_flags & MSG_CMSG_CLOEXEC) ? O_CLOEXEC : 0;

	int fdmax = min_t(int, scm_max_fds(msg), scm->fp->count);

	int __user *cmsg_data = CMSG_USER_DATA(cm);

	int err = 0, i;



	if (msg->msg_flags & MSG_CMSG_COMPAT) {

		scm_detach_fds_compat(msg, scm);

		return;

	}



	for (i = 0; i < fdmax; i++) {

		err = __scm_install_fd(scm->fp->fp[i], cmsg_data + i, o_flags);

		if (err)

			break;

	}



	if (i > 0)  {

		int cmlen = CMSG_LEN(i * sizeof(int));



		err = put_user(SOL_SOCKET, &cm->cmsg_level);

		if (!err)

			err = put_user(SCM_RIGHTS, &cm->cmsg_type);
@@ -343,12 +350,13 @@ void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm) 
			msg->msg_controllen -= cmlen;

		}

	}

	if (i < fdnum || (fdnum && fdmax <= 0))



	if (i < scm->fp->count || (scm->fp->count && fdmax <= 0))

		msg->msg_flags |= MSG_CTRUNC;



	/*

	 * All of the files that fit in the message have had their

	 * usage counts incremented, so we just free the list.

	 * All of the files that fit in the message have had their usage counts

	 * incremented, so we just free the list.

	 */

	__scm_destroy(scm);

}