Commit 98382f41 authored Aug 04, 2011 by Anton Blanchard Committed by David S. Miller Aug 05, 2011

net: Cap number of elements for sendmmsg



To limit the amount of time we can spend in sendmmsg, cap the
number of elements to UIO_MAXIOV (currently 1024).

For error handling an application using sendmmsg needs to retry at
the first unsent message, so capping is simpler and requires less
application logic than returning EINVAL.

Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: stable <stable@kernel.org> [3.0+]
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 728ffb86

net/socket.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -1999,6 +1999,9 @@ int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
		struct compat_mmsghdr __user *compat_entry;
		struct msghdr msg_sys;

		if (vlen > UIO_MAXIOV)
		vlen = UIO_MAXIOV;

		datagrams = 0;

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