Merged revisions 331575 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.8

........
  r331575 | rmudgett | 2011-08-11 16:39:58 -0500 (Thu, 11 Aug 2011) | 9 lines

  Segfault in shell_helper in func_shell.c.

  The return value of popen() was not checked for failure to open.

  (closes issue ASTERISK-18109)
  JIRA SWP-3633
  Reported by: Michael Myles
  Tested by: rmudgett
........

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/10@331576 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/funcs/func_shell.c b/funcs/func_shell.c
index 1f274b83d5635f21cefee4a3c6bfa7dbc7123c10..2f34f62ab8b36299dacaa80a2c0169d6f9286695 100644 (file)
--- a/funcs/func_shell.c
+++ b/funcs/func_shell.c
@@ -42,29 +42,38 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 static int shell_helper(struct ast_channel *chan, const char *cmd, char *data,
                                         char *buf, size_t len)
 {
+       int res = 0;
+
        if (ast_strlen_zero(data)) {
                ast_log(LOG_WARNING, "Missing Argument!  Example:  Set(foo=${SHELL(echo \"bar\")})\n");
                return -1;
        }
 
-       if (chan)
+       if (chan) {
                ast_autoservice_start(chan);
+       }
 
        if (len >= 1) {
                FILE *ptr;
                char plbuff[4096];
 
                ptr = popen(data, "r");
-               while (fgets(plbuff, sizeof(plbuff), ptr)) {
-                       strncat(buf, plbuff, len - strlen(buf) - 1);
+               if (ptr) {
+                       while (fgets(plbuff, sizeof(plbuff), ptr)) {
+                               strncat(buf, plbuff, len - strlen(buf) - 1);
+                       }
+                       pclose(ptr);
+               } else {
+                       ast_log(LOG_WARNING, "Failed to execute shell command '%s'\n", data);
+                       res = -1;
                }
-               pclose(ptr);
        }
 
-       if (chan)
+       if (chan) {
                ast_autoservice_stop(chan);
+       }
 
-       return 0;
+       return res;
 }
 
 /*** DOCUMENTATION