vallen is verified to be less than len, therefore, it can never

be the case that `vallen >= len + sizeof(rhostname)`.

This PR fixes the check so the `rhostname` array does not overflow.

Reported-by: Github Security Lab <[email protected]>
Signed-off-by: Alvaro Muñoz <[email protected]>
This commit is contained in:
Github Security Lab
2020-03-20 01:23:36 +08:00
committed by David Čermák
parent dd3b301750
commit 44af234a80
+2 -2
View File
@@ -1417,7 +1417,7 @@ static void eap_request(ppp_pcb *pcb, u_char *inp, int id, int len) {
}
/* Not so likely to happen. */
if (vallen >= len + sizeof (rhostname)) {
if (len - vallen >= sizeof (rhostname)) {
ppp_dbglog("EAP: trimming really long peer name down");
MEMCPY(rhostname, inp + vallen, sizeof (rhostname) - 1);
rhostname[sizeof (rhostname) - 1] = '\0';
@@ -1845,7 +1845,7 @@ static void eap_response(ppp_pcb *pcb, u_char *inp, int id, int len) {
}
/* Not so likely to happen. */
if (vallen >= len + sizeof (rhostname)) {
if (len - vallen >= sizeof (rhostname)) {
ppp_dbglog("EAP: trimming really long peer name down");
MEMCPY(rhostname, inp + vallen, sizeof (rhostname) - 1);
rhostname[sizeof (rhostname) - 1] = '\0';