[PATCH] let binfmt_misc optionally preserve argv[1]

From: Bjorn Helgaas (bjorn.helgaas_at_hp.com)
Date: 12/31/03

  • Next message: Hugo Mills: "Re: [PATCH] adaptec 1210sa" 
    To: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
Date:	Tue, 30 Dec 2003 17:06:39 -0700

    Originally by David Mosberger; here's his description:

    This makes it possible for binfmt_misc to optionally preserve the
    contents of argv[1]. This is needed for building accurate simulators
    which are invoked via binfmt_misc. I had brought up this patch a while
    ago (see URL below) and there was no negative feedback (OK, there was no
    feedback at all... ;-).

    The patch is trivial and the new behavior is triggered only if the
    letter "P" (for "preserve") is appended to the binfmt_misc registration
    string, so it shold be completely safe.

    http://groups.google.com/groups?q=mosberger+binfmt_misc&hl=en&lr=&ie=UTF-8&oe=UT
    F-8&selm=200209092241.g89MfPS5001013%40napali.hpl.hp.com&rnum=1

    This has been in 2.6 for 16 months:
        http://linux.bkbits.net:8080/linux-2.5/diffs/fs/binfmt_misc.c@1.16?nav=index.html|src/.|src/fs|hist/fs/binfmt_misc.c

    diff -urN linux-2.4/fs/binfmt_misc.c linux-ia64-2.4/fs/binfmt_misc.c
    --- linux-2.4/fs/binfmt_misc.c 2003-12-29 17:05:24.000000000 -0700
    +++ linux-ia64-2.4/fs/binfmt_misc.c 2003-12-29 17:06:12.000000000 -0700
    @@ -35,6 +35,7 @@
     static int enabled = 1;
     
     enum {Enabled, Magic};
    +#define MISC_FMT_PRESERVE_ARGV0 (1<<31)
     
     typedef struct {
             struct list_head list;
    @@ -121,7 +122,9 @@
             bprm->file = NULL;
     
             /* Build args for interpreter */
    - remove_arg_zero(bprm);
    + if (!(fmt->flags & MISC_FMT_PRESERVE_ARGV0)) {
    + remove_arg_zero(bprm);
    + }
             retval = copy_strings_kernel(1, &bprm->filename, bprm);
             if (retval < 0) goto _ret;
             bprm->argc++;
    @@ -287,6 +290,11 @@
             if (!e->interpreter[0])
                     goto Einval;
     
    + if (*p == 'P') {
    + p++;
    + e->flags |= MISC_FMT_PRESERVE_ARGV0;
    + }
    +
             if (*p == '\n')
                     p++;
             if (p != buf + count)

    -
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  • Next message: Hugo Mills: "Re: [PATCH] adaptec 1210sa"