svn commit: r316495 - head/usr.bin/grep/regex

[Conrad Meyer]

Author: cem
Date: Tue Apr  4 17:05:37 2017
New Revision: 316495
URL: https://svnweb.freebsd.org/changeset/base/316495

Log:
  bsdgrep(1): Fix errors with invalid expressions
  
  Invalid expressions with an ultimate compiled pattern length of 0 (e.g.,
  "grep -E {") were not taken into account and caused a segfault while trying
  to fill in the good suffix table.
  
  Submitted by:	Kyle Evans <kevans91 at ksu.edu>
  Reviewed by:	me
  Differential Revision:	https://reviews.freebsd.org/D10113

Modified:
  head/usr.bin/grep/regex/tre-fastmatch.c

Modified: head/usr.bin/grep/regex/tre-fastmatch.c
==============================================================================
--- head/usr.bin/grep/regex/tre-fastmatch.c	Tue Apr  4 16:54:46 2017	(r316494)
+++ head/usr.bin/grep/regex/tre-fastmatch.c	Tue Apr  4 17:05:37 2017	(r316495)
@@ -337,7 +337,7 @@ static int	fastcmp(const fastmatch_t *fg
  * Fills in the good suffix table for SB/MB strings.
  */
 #define FILL_BMGS							\
-  if (!fg->hasdot)							\
+  if (fg->len > 0 && !fg->hasdot)					\
     {									\
       fg->sbmGs = malloc(fg->len * sizeof(int));			\
       if (!fg->sbmGs)							\
@@ -353,7 +353,7 @@ static int	fastcmp(const fastmatch_t *fg
  * Fills in the good suffix table for wide strings.
  */
 #define FILL_BMGS_WIDE							\
-  if (!fg->hasdot)							\
+  if (fg->wlen > 0 && !fg->hasdot)					\
     {									\
       fg->bmGs = malloc(fg->wlen * sizeof(int));			\
       if (!fg->bmGs)							\