Handle fork(), pipe() etc failures in signing passphrase check

- Actually check the return codes from various things and handle
  the failures. This is nowhere near 100% correct still, but
  at least within spitting distance from the ballpark.
- Incidentally this eliminates the last compiler warning on the rpm
  codebase with current gcc (4.8.0), wohoo.
(cherry picked from commit 7fd03b0abf0e9522890d1602867f3264b01e9961)

diff --git a/rpmsign.c b/rpmsign.c
index e29864e..b8e5598 100644 (file)
--- a/rpmsign.c
+++ b/rpmsign.c
@@ -45,29 +45,38 @@ static int checkPassPhrase(const char * passPhrase)
 {
     int passPhrasePipe[2];
     int pid, status;
-    int rc;
+    int rc = -1;
     int xx;
 
     if (passPhrase == NULL)
        return -1;
 
     passPhrasePipe[0] = passPhrasePipe[1] = 0;
-    xx = pipe(passPhrasePipe);
-    if (!(pid = fork())) {
+    if (pipe(passPhrasePipe))
+       return -1;
+
+    pid = fork();
+    if (pid < 0) {
+       close(passPhrasePipe[0]);
+       close(passPhrasePipe[1]);
+       return -1;
+    }
+
+    if (pid == 0) {
        char * cmd, * gpg_path;
        char *const *av;
        int fdno;
 
-       xx = close(STDIN_FILENO);
-       xx = close(STDOUT_FILENO);
-       xx = close(passPhrasePipe[1]);
+       close(STDIN_FILENO);
+       close(STDOUT_FILENO);
+       close(passPhrasePipe[1]);
        if ((fdno = open("/dev/null", O_RDONLY)) != STDIN_FILENO) {
            xx = dup2(fdno, STDIN_FILENO);
-           xx = close(fdno);
+           close(fdno);
        }
        if ((fdno = open("/dev/null", O_WRONLY)) != STDOUT_FILENO) {
            xx = dup2(fdno, STDOUT_FILENO);
-           xx = close(fdno);
+           close(fdno);
        }
        xx = dup2(passPhrasePipe[0], 3);
 
@@ -79,22 +88,23 @@ static int checkPassPhrase(const char * passPhrase)
        
        cmd = rpmExpand("%{?__gpg_check_password_cmd}", NULL);
        rc = poptParseArgvString(cmd, NULL, (const char ***)&av);
-       if (!rc)
+       if (xx >= 0 && rc == 0) {
            rc = execve(av[0], av+1, environ);
-
-       fprintf(stderr, _("Could not exec %s: %s\n"), "gpg",
-                   strerror(errno));
+           fprintf(stderr, _("Could not exec %s: %s\n"), "gpg",
+                       strerror(errno));
+       }
        _exit(EXIT_FAILURE);
     }
 
-    xx = close(passPhrasePipe[0]);
+    close(passPhrasePipe[0]);
     xx = write(passPhrasePipe[1], passPhrase, strlen(passPhrase));
     xx = write(passPhrasePipe[1], "\n", 1);
-    xx = close(passPhrasePipe[1]);
+    close(passPhrasePipe[1]);
 
-    (void) waitpid(pid, &status, 0);
+    if (xx >= 0 && waitpid(pid, &status, 0) >= 0)
+       rc = (WIFEXITED(status) && WEXITSTATUS(status) == 0) ? 0 : 1;
 
-    return ((WIFEXITED(status) && WEXITSTATUS(status) == 0)) ? 0 : 1;
+    return rc;
 }
 
 /* TODO: permit overriding macro setup on the command line */