From a50436f2cd6e85794f7e1aad795ca8302177b896 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Wed, 17 Mar 2010 06:04:14 +0000 Subject: net: ipmr/ip6mr: fix potential out-of-bounds vif_table access mfc_parent of cache entries is used to index into the vif_table and is initialised from mfcctl->mfcc_parent. This can take values of to 2^16-1, while the vif_table has only MAXVIFS (32) entries. The same problem affects ip6mr. Refuse invalid values to fix a potential out-of-bounds access. Unlike the other validity checks, this is checked in ipmr_mfc_add() instead of the setsockopt handler since its unused in the delete path and might be uninitialized. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- net/ipv4/ipmr.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'net/ipv4/ipmr.c') diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index 8582e12e4a62..0b9d03c54dc3 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -802,6 +802,9 @@ static int ipmr_mfc_add(struct net *net, struct mfcctl *mfc, int mrtsock) int line; struct mfc_cache *uc, *c, **cp; + if (mfc->mfcc_parent >= MAXVIFS) + return -ENFILE; + line = MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr); for (cp = &net->ipv4.mfc_cache_array[line]; -- cgit v1.2.3