svn commit: r314714 - head/bin/kill

[Bryan Drewery]

Author: bdrewery
Date: Sun Mar  5 21:56:04 2017
New Revision: 314714
URL: https://svnweb.freebsd.org/changeset/base/314714

Log:
  Don't kill pid -1 on overflow from strtol(3).
  
  Store the result in a proper long and then compare to the proper pid_t
  for overflow, so that no MD assumptions are made.
  
  Reviewed by:	jilles
  MFC after:	2 weeks
  Differential Revision:	https://reviews.freebsd.org/D9887

Modified:
  head/bin/kill/kill.c

Modified: head/bin/kill/kill.c
==============================================================================
--- head/bin/kill/kill.c	Sun Mar  5 21:44:29 2017	(r314713)
+++ head/bin/kill/kill.c	Sun Mar  5 21:56:04 2017	(r314714)
@@ -66,7 +66,9 @@ static void usage(void);
 int
 main(int argc, char *argv[])
 {
-	int errors, numsig, pid, ret;
+	long pidl;
+	pid_t pid;
+	int errors, numsig, ret;
 	char *ep;
 
 	if (argc < 2)
@@ -137,8 +139,10 @@ main(int argc, char *argv[])
 		else
 #endif
 		{
-			pid = strtol(*argv, &ep, 10);
-			if (!**argv || *ep)
+			pidl = strtol(*argv, &ep, 10);
+			/* Check for overflow of pid_t. */
+			pid = (pid_t)pidl;
+			if (!**argv || *ep || pid != pidl)
 				errx(2, "illegal process id: %s", *argv);
 			ret = kill(pid, numsig);
 		}