Accepting request 566471 from home:kbabioch:branches:devel:libraries:c_c++

- CVE-2016-8859.patch: Fix multiple integer overflows which allowed
  attackers to cause memory corruption via a large number of (1) states or
  (2) tags, which triggered an out-of-bounds write (bnc#1005483)

OBS-URL: https://build.opensuse.org/request/show/566471
OBS-URL: https://build.opensuse.org/package/show/devel:libraries:c_c++/tre?expand=0&rev=17

CVE-2016-8859.patch

@@ -0,0 +1,73 @@
+From c3edc06d1e1360f3570db9155d6b318ae0d0f0f7 Mon Sep 17 00:00:00 2001
+From: Rich Felker <dalias@aerifal.cx>
+Date: Thu, 6 Oct 2016 18:34:58 -0400
+Subject: fix missing integer overflow checks in regexec buffer size
+ computations
+
+most of the possible overflows were already ruled out in practice by
+regcomp having already succeeded performing larger allocations.
+however at least the num_states*num_tags multiplication can clearly
+overflow in practice. for safety, check them all, and use the proper
+type, size_t, rather than int.
+
+also improve comments, use calloc in place of malloc+memset, and
+remove bogus casts.
+---
+ src/regex/regexec.c | 23 ++++++++++++++++++-----
+ 1 file changed, 18 insertions(+), 5 deletions(-)
+
+Note: patch was modified to apply to tre, parts were taken from
+https://github.com/laurikari/tre/issues/37
+
+--- a/lib/tre-match-parallel.c
++++ b/lib/tre-match-parallel.c
+@@ -59,6 +59,7 @@ char *alloca ();
+ #ifdef HAVE_MALLOC_H
+ #include <malloc.h>
+ #endif /* HAVE_MALLOC_H */
++#include <stdint.h>
+ 
+ #include "tre-internal.h"
+ #include "tre-match-utils.h"
+@@ -150,11 +151,24 @@ tre_tnfa_run_parallel(const tre_tnfa_t *
+ 
+   /* Allocate memory for temporary data required for matching.	This needs to
+      be done for every matching operation to be thread safe.  This allocates
+-     everything in a single large block from the stack frame using alloca()
+-     or with malloc() if alloca is unavailable. */
++     everything in a single large block with calloc(). */
+   {
+-    int tbytes, rbytes, pbytes, xbytes, total_bytes;
++    size_t tbytes, rbytes, pbytes, xbytes, total_bytes;
+     char *tmp_buf;
++
++    /* Ensure that tbytes and xbytes*num_states cannot overflow, and that
++     * they don't contribute more than 1/8 of SIZE_MAX to total_bytes. */
++    if (num_tags > SIZE_MAX/(8 * sizeof(int) * tnfa->num_states))
++      return REG_BADPAT;
++
++    /* Likewise check rbytes. */
++    if (tnfa->num_states+1 > SIZE_MAX/(8 * sizeof(*reach_next)))
++      return REG_BADPAT;
++
++    /* Likewise check pbytes. */
++    if (tnfa->num_states > SIZE_MAX/(8 * sizeof(*reach_pos)))
++      return REG_BADPAT;
++
+     /* Compute the length of the block we need. */
+     tbytes = sizeof(*tmp_tags) * num_tags;
+     rbytes = sizeof(*reach_next) * (tnfa->num_states + 1);
+@@ -168,11 +182,11 @@ tre_tnfa_run_parallel(const tre_tnfa_t *
+ #ifdef TRE_USE_ALLOCA
+     buf = alloca(total_bytes);
+ #else /* !TRE_USE_ALLOCA */
+-    buf = xmalloc((unsigned)total_bytes);
++    buf = xmalloc(total_bytes);
+ #endif /* !TRE_USE_ALLOCA */
+     if (buf == NULL)
+       return REG_ESPACE;
+-    memset(buf, 0, (size_t)total_bytes);
++    memset(buf, 0, total_bytes);
+ 
+     /* Get the various pointers within tmp_buf (properly aligned). */
+     tmp_tags = (void *)buf;