irda: validate peer name and attribute lengths

BugLink: http://bugs.launchpad.net/bugs/761134

commit d370af0ef7951188daeb15bae75db7ba57c67846 upstream.

Length fields provided by a peer for names and attributes may be longer
than the destination array sizes.  Validate lengths to prevent stack
buffer overflows.

Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

diff --git a/net/irda/iriap.c b/net/irda/iriap.c
index 5b743bd..3647753 100644 (file)
--- a/net/irda/iriap.c
+++ b/net/irda/iriap.c
@@ -656,10 +656,16 @@ static void iriap_getvaluebyclass_indication(struct iriap_cb *self,
        n = 1;
 
        name_len = fp[n++];
+
+       IRDA_ASSERT(name_len < IAS_MAX_CLASSNAME + 1, return;);
+
        memcpy(name, fp+n, name_len); n+=name_len;
        name[name_len] = '\0';
 
        attr_len = fp[n++];
+
+       IRDA_ASSERT(attr_len < IAS_MAX_ATTRIBNAME + 1, return;);
+
        memcpy(attr, fp+n, attr_len); n+=attr_len;
        attr[attr_len] = '\0';