[RFC PATCH 03/20] selinux: avoid avtab overflows

["Christian Göttsche" <cgzones@googlemail.com>]

Prevent inserting more than the supported U32_MAX number of entries.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
---
 security/selinux/ss/avtab.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c
index fbf51986afcf..9c150fba3fa6 100644
--- a/security/selinux/ss/avtab.c
+++ b/security/selinux/ss/avtab.c
@@ -110,7 +110,7 @@ static int avtab_insert(struct avtab *h, const struct avtab_key *key,
 	struct avtab_node *prev, *cur, *newnode;
 	u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD);
 
-	if (!h || !h->nslot)
+	if (!h || !h->nslot || h->nel == U32_MAX)
 		return -EINVAL;
 
 	hvalue = avtab_hash(key, h->mask);
@@ -156,7 +156,7 @@ struct avtab_node *avtab_insert_nonunique(struct avtab *h,
 	struct avtab_node *prev, *cur;
 	u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD);
 
-	if (!h || !h->nslot)
+	if (!h || !h->nslot || h->nel == U32_MAX)
 		return NULL;
 	hvalue = avtab_hash(key, h->mask);
 	for (prev = NULL, cur = h->htable[hvalue];
-- 
2.40.1