svn commit: r250882 - head/usr.bin/split

[Eitan Adler]

Author: eadler
Date: Tue May 21 19:56:03 2013
New Revision: 250882
URL: http://svnweb.freebsd.org/changeset/base/250882

Log:
  Avoid signed overflow in error handling code.
  
  Reviewed by:	cperciva, bjk

Modified:
  head/usr.bin/split/split.c

Modified: head/usr.bin/split/split.c
==============================================================================
--- head/usr.bin/split/split.c	Tue May 21 19:32:35 2013	(r250881)
+++ head/usr.bin/split/split.c	Tue May 21 19:56:03 2013	(r250882)
@@ -379,8 +379,10 @@ newfile(void)
 
 	/* maxfiles = pattlen^sufflen, but don't use libm. */
 	for (maxfiles = 1, i = 0; i < sufflen; i++)
-		if ((maxfiles *= pattlen) <= 0)
+		if (LONG_MAX / pattlen < maxfiles)
 			errx(EX_USAGE, "suffix is too long (max %ld)", i);
+		else
+			maxfiles *= pattlen;
 
 	if (fnum == maxfiles)
 		errx(EX_DATAERR, "too many files");