Merge remote-tracking branch 'tor-github/pr/1424' into maint-0.4.0

2 files changed, 19 insertions, 8 deletions

diff --git a/src/lib/process/process_unix.c b/src/lib/process/process_unix.c
index 790ab897e9..b102afff44 100644
--- a/src/lib/process/process_unix.c
+++ b/src/lib/process/process_unix.c
@@ -253,22 +253,15 @@ process_unix_exec(process_t *process)
     process_environment_t *env = process_get_environment(process);
 
     /* Call the requested program. */
-    retval = execve(argv[0], argv, env->unixoid_environment_block);
+    execve(argv[0], argv, env->unixoid_environment_block);
 
     /* If we made it here it is because execve failed :-( */
-    if (-1 == retval)
-      fprintf(stderr, "Call to execve() failed: %s", strerror(errno));
-
     tor_free(argv);
     process_environment_free(env);
 
-    tor_assert_unreached();
-
  error:
-    /* LCOV_EXCL_START */
     fprintf(stderr, "Error from child process: %s", strerror(errno));
     _exit(1);
-    /* LCOV_EXCL_STOP */
   }
 
   /* We are in the parent process. */
diff --git a/src/lib/process/process_win32.c b/src/lib/process/process_win32.c
index ddbe76bfd9..1b1de6ad55 100644
--- a/src/lib/process/process_win32.c
+++ b/src/lib/process/process_win32.c
@@ -234,6 +234,24 @@ process_win32_exec(process_t *process)
     CloseHandle(stdin_pipe_read);
     CloseHandle(stdin_pipe_write);
 
+    /* In the Unix backend, we do not get an error in the Tor process when a
+     * child process fails to spawn its target executable since we need to
+     * first do the fork() call in the Tor process and then the child process
+     * is responsible for doing the call to execve().
+     *
+     * This means that the user of the process_exec() API must check for
+     * whether it returns PROCESS_STATUS_ERROR, which will rarely happen on
+     * Unix, but will happen for error cases on Windows where it does not
+     * happen on Unix. For example: when the target executable does not exist
+     * on the file system.
+     *
+     * To have somewhat feature compatibility between the Unix and the Windows
+     * backend, we here notify the process_t owner that the process have exited
+     * (even though it never managed to run) to ensure that the exit callback
+     * is executed.
+     */
+    process_notify_event_exit(process, 0);
+
     return PROCESS_STATUS_ERROR;
   }