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Commit 5da028a8 authored by Al Viro's avatar Al Viro
Browse files

get_compat_msghdr(): get rid of field-by-field copyin 



Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent ffb07550

net/compat.c

+14 −17
Original line number Diff line number Diff line
@@ -37,21 +37,16 @@ int get_compat_msghdr(struct msghdr *kmsg, 
		      struct sockaddr __user **save_addr,

		      struct iovec **iov)

{

	compat_uptr_t uaddr, uiov, tmp3;

	compat_size_t nr_segs;

	struct compat_msghdr msg;

	ssize_t err;



	if (!access_ok(VERIFY_READ, umsg, sizeof(*umsg)) ||

	    __get_user(uaddr, &umsg->msg_name) ||

	    __get_user(kmsg->msg_namelen, &umsg->msg_namelen) ||

	    __get_user(uiov, &umsg->msg_iov) ||

	    __get_user(nr_segs, &umsg->msg_iovlen) ||

	    __get_user(tmp3, &umsg->msg_control) ||

	    __get_user(kmsg->msg_controllen, &umsg->msg_controllen) ||

	    __get_user(kmsg->msg_flags, &umsg->msg_flags))

	if (copy_from_user(&msg, umsg, sizeof(*umsg)))

		return -EFAULT;



	if (!uaddr)

	kmsg->msg_flags = msg.msg_flags;

	kmsg->msg_namelen = msg.msg_namelen;



	if (!msg.msg_name)

		kmsg->msg_namelen = 0;



	if (kmsg->msg_namelen < 0)
@@ -59,14 +54,16 @@ int get_compat_msghdr(struct msghdr *kmsg, 


	if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))

		kmsg->msg_namelen = sizeof(struct sockaddr_storage);

	kmsg->msg_control = compat_ptr(tmp3);



	kmsg->msg_control = compat_ptr(msg.msg_control);

	kmsg->msg_controllen = msg.msg_controllen;



	if (save_addr)

		*save_addr = compat_ptr(uaddr);

		*save_addr = compat_ptr(msg.msg_name);



	if (uaddr && kmsg->msg_namelen) {

	if (msg.msg_name && kmsg->msg_namelen) {

		if (!save_addr) {

			err = move_addr_to_kernel(compat_ptr(uaddr),

			err = move_addr_to_kernel(compat_ptr(msg.msg_name),

						  kmsg->msg_namelen,

						  kmsg->msg_name);

			if (err < 0)
@@ -77,13 +74,13 @@ int get_compat_msghdr(struct msghdr *kmsg, 
		kmsg->msg_namelen = 0;

	}



	if (nr_segs > UIO_MAXIOV)

	if (msg.msg_iovlen > UIO_MAXIOV)

		return -EMSGSIZE;



	kmsg->msg_iocb = NULL;



	return compat_import_iovec(save_addr ? READ : WRITE,

				   compat_ptr(uiov), nr_segs,

				   compat_ptr(msg.msg_iov), msg.msg_iovlen,

				   UIO_FASTIOV, iov, &kmsg->msg_iter);

}