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>
diff --git a/net/socket.c b/net/socket.c
index e4ed235..b5c6de4 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -1999,6 +1999,9 @@
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);