Commit effee6a0 authored Oct 09, 2006 by Miklos Szeredi Committed by David S. Miller Oct 11, 2006

[NET]: File descriptor loss while receiving SCM_RIGHTS



If more than one file descriptor was sent with an SCM_RIGHTS message,
and on the receiving end, after installing a nonzero (but not all)
file descritpors the process runs out of fds, then the already
installed fds will be lost (userspace will have no way of knowing
about them).

The following patch makes sure, that at least the already installed
fds are sent to userspace.  It doesn't solve the issue of losing file
descriptors in case of an EFAULT on the userspace buffer.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 6aa2551c

net/compat.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -285,7 +285,6 @@ void scm_detach_fds_compat(struct msghdr kmsg, struct scm_cookie scm)

		if (i > 0) {
		int cmlen = CMSG_COMPAT_LEN(i * sizeof(int));
		if (!err)
		err = put_user(SOL_SOCKET, &cm->cmsg_level);
		if (!err)
		err = put_user(SCM_RIGHTS, &cm->cmsg_type);

net/core/scm.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -245,7 +245,6 @@ void scm_detach_fds(struct msghdr msg, struct scm_cookie scm)
		if (i > 0)
		{
		int cmlen = CMSG_LEN(i*sizeof(int));
		if (!err)
		err = put_user(SOL_SOCKET, &cm->cmsg_level);
		if (!err)
		err = put_user(SCM_RIGHTS, &cm->cmsg_type);

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