Commit 3f91bd42 authored by Sam Ravnborg's avatar Sam Ravnborg Committed by David S. Miller
Browse files

can: Fix copy_from_user() results interpretation 



Both copy_to_ and _from_user return the number of bytes, that failed to
reach their destination, not the 0/-EXXX values.

Based on patch from Pavel Emelyanov <xemul@openvz.org>

Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
Acked-by: default avatarOliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5c5d6dab

net/can/raw.c

+10 −11
Original line number Diff line number Diff line
@@ -435,15 +435,13 @@ static int raw_setsockopt(struct socket *sock, int level, int optname, 
			if (!filter)

				return -ENOMEM;



			err = copy_from_user(filter, optval, optlen);

			if (err) {

			if (copy_from_user(filter, optval, optlen)) {

				kfree(filter);

				return err;

				return -EFAULT;

			}

		} else if (count == 1) {

			err = copy_from_user(&sfilter, optval, optlen);

			if (err)

				return err;

			if (copy_from_user(&sfilter, optval, optlen))

				return -EFAULT;

		}



		lock_sock(sk);
@@ -493,9 +491,8 @@ static int raw_setsockopt(struct socket *sock, int level, int optname, 
		if (optlen != sizeof(err_mask))

			return -EINVAL;



		err = copy_from_user(&err_mask, optval, optlen);

		if (err)

			return err;

		if (copy_from_user(&err_mask, optval, optlen))

			return -EFAULT;



		err_mask &= CAN_ERR_MASK;
@@ -531,7 +528,8 @@ static int raw_setsockopt(struct socket *sock, int level, int optname, 
		if (optlen != sizeof(ro->loopback))

			return -EINVAL;



		err = copy_from_user(&ro->loopback, optval, optlen);

		if (copy_from_user(&ro->loopback, optval, optlen))

			return -EFAULT;



		break;
@@ -539,7 +537,8 @@ static int raw_setsockopt(struct socket *sock, int level, int optname, 
		if (optlen != sizeof(ro->recv_own_msgs))

			return -EINVAL;



		err = copy_from_user(&ro->recv_own_msgs, optval, optlen);

		if (copy_from_user(&ro->recv_own_msgs, optval, optlen))

			return -EFAULT;



		break;

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