From e56a2ada719c5cfac5ed61a52a80ade86c0f5957 Mon Sep 17 00:00:00 2001 From: Alan Coopersmith Date: Sat, 2 Mar 2013 10:51:51 -0800 Subject: unvalidated index in _XkbReadModifierMap() [CVE-2013-1997 8/15] If the X server returns modifier map indexes outside the range of the number of keys it told us to allocate, out of bounds memory writes could occur. Reported-by: Ilja Van Sprundel Signed-off-by: Alan Coopersmith Reviewed-by: Matthieu Herrb --- src/xkb/XKBGetMap.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/src/xkb/XKBGetMap.c b/src/xkb/XKBGetMap.c index af93a5cb..a68455bd 100644 --- a/src/xkb/XKBGetMap.c +++ b/src/xkb/XKBGetMap.c @@ -390,6 +390,9 @@ register int i; unsigned char *wire; if ( rep->totalModMapKeys>0 ) { + if ( ((int)rep->firstModMapKey + rep->nModMapKeys) > + (xkb->max_key_code + 1)) + return BadLength; if ((xkb->map->modmap==NULL)&& (XkbAllocClientMap(xkb,XkbModifierMapMask,0)!=Success)) { return BadAlloc; @@ -402,6 +405,8 @@ unsigned char *wire; if (!wire) return BadLength; for (i=0;itotalModMapKeys;i++,wire+=2) { + if (wire[0] > xkb->max_key_code || wire[1] > xkb->max_key_code) + return BadLength; xkb->map->modmap[wire[0]]= wire[1]; } } -- cgit v1.2.3