From bb7abd9da9badc6cb825c636867cbef827141f36 Mon Sep 17 00:00:00 2001 From: Mike DePaulo Date: Sun, 8 Feb 2015 22:19:01 -0500 Subject: CVE-2014-0211: integer overflow in fs_read_extent_info() from xorg/lib/libXfont commit c578408c1fd4db09e4e3173f8a9e65c81cc187c1 fs_read_extent_info() parses a reply from the font server. The reply contains a 32bit number of elements field which is used to calculate a buffer length. There is an integer overflow in this calculation which can lead to memory corruption. --- nx-X11/lib/font/fc/fserve.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/nx-X11/lib/font/fc/fserve.c b/nx-X11/lib/font/fc/fserve.c index 2a6f6c97b..639964c55 100644 --- a/nx-X11/lib/font/fc/fserve.c +++ b/nx-X11/lib/font/fc/fserve.c @@ -73,6 +73,7 @@ in this Software without prior written authorization from The Open Group. #include "fservestr.h" #include #include +#include #include #define Time_t time_t @@ -1060,7 +1061,16 @@ fs_read_extent_info(FontPathElementPtr fpe, FSBlockDataPtr blockrec) numInfos *= 2; haveInk = TRUE; } - ci = pCI = (CharInfoPtr) xalloc(sizeof(CharInfoRec) * numInfos); + if (numInfos >= (INT_MAX / sizeof(CharInfoRec))) { +#ifdef DEBUG + fprintf(stderr, + "fsQueryXExtents16: numInfos (%d) >= %ld\n", + numInfos, (INT_MAX / sizeof(CharInfoRec))); +#endif + pCI = NULL; + } + else + pCI = malloc(sizeof(CharInfoRec) * numInfos); if (!pCI) { -- cgit v1.2.3