Re: 4.3.90 release candidate segfaults on linux and solaris

[Dmitry Goncharov]

On Sun, Sep 25, 2022 at 2:09 AM Martin Dorey
<Martin.Dorey@hitachivantara.com> wrote:
> And vfork is where that happens.  If I’ve followed the thicket of #ifdef 
> correctly and understood the vfork man page, then this is illegal when using 
> vfork:
>
> https://github.com/mirror/make/blob/master/src/job.c#L2556


Thanks, Martin.
This is indeed the culprit.
I was able to find a linux where this reproduces. However, the this
does this reproduce on my sun. Denis, can you please try this patch on
your sun?

regards, Dmitry

Here is a patch

index d12a9138..1ed71f0a 100644
--- a/src/job.c
+++ b/src/job.c
@@ -2286,6 +2286,8 @@ child_execute_job (struct childbase *child, int
good_stdin, char **argv)
   posix_spawnattr_t attr;
   posix_spawn_file_actions_t fa;
   short flags = 0;
+#else
+  char **parent_environ = environ;
 #endif

   /* Divert child output if we want to capture it.  */
@@ -2301,7 +2303,12 @@ child_execute_job (struct childbase *child, int
good_stdin, char **argv)

   pid = vfork();
   if (pid != 0)
+    {
+      /* The child sets environ to child->environment before calling execvp.
+       * Restore it here.  */
+      environ = parent_environ;
       return pid;
+    }

   /* We are the child.  */
   unblock_all_sigs ();
@@ -2552,7 +2559,8 @@ exec_command (char **argv, char **envp)
     errno = ENOEXEC;

 # else
-  /* Run the program.  */
+  /* Run the program.
+   * The parent has to restore environ.  */
   environ = envp;
   execvp (argv[0], argv);