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Re: [kernel-hardening] Re: [PATCH v1 0/2] Introduce the initify gcc plugin

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On Tue, 28 Jun 2016 14:49:15 -0700, Joe Perches said:

> Another potentially useful plugin, especially for embedded systems,
> would be to compress any string literal marked with
>
> 	 __attribute__((format(printf, string-index,)))
>
> and decompress the compressed format on the stack in lib/vsprintf.c
> vsnprintf just before use.

Are there enough such strings in the kernel to make it worth the effort?
I'm assuming that the string literals in printk("some string here") are
automatically so marked?

Is there a minimum length under which the compression overhead actually
makes it larger?  For instance, "a" can't be compressed, because you need
to indicate there's 1 "a" and 1 \0, while "aaaaaa" can, because you can
express it as '6*"a" 1 \0 in only 4 bytes not 7.  But exactly where the
cutoff is, I have no idea (and is probably *very* text-dependent, as
"aaaaaa" and "abcdef" will compress differently....)

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[PATCH v1 0/2] Introduce the initify gcc plugin Emese Revfy <re.emese@gmail.com> - 2016-06-28 13:30 +0200
  [PATCH v1 2/2] Mark functions with the __nocapture attribute Emese Revfy <re.emese@gmail.com> - 2016-06-28 13:40 +0200
    Re: [PATCH v1 2/2] Mark functions with the __nocapture attribute Joe Perches <joe@perches.com> - 2016-06-28 18:50 +0200
      Re: [PATCH v1 2/2] Mark functions with the __nocapture attribute Emese Revfy <re.emese@gmail.com> - 2016-06-28 22:40 +0200
        Re: [PATCH v1 2/2] Mark functions with the __nocapture attribute Joe Perches <joe@perches.com> - 2016-06-28 23:10 +0200
          Re: [PATCH v1 2/2] Mark functions with the __nocapture attribute Emese Revfy <re.emese@gmail.com> - 2016-06-29 20:50 +0200
            Re: [PATCH v1 2/2] Mark functions with the __nocapture attribute Joe Perches <joe@perches.com> - 2016-06-30 02:20 +0200
              Re: [PATCH v1 2/2] Mark functions with the __nocapture attribute Emese Revfy <re.emese@gmail.com> - 2016-07-01 16:00 +0200
    Re: [PATCH v1 2/2] Mark functions with the __nocapture attribute Rasmus Villemoes <linux@rasmusvillemoes.dk> - 2016-06-28 23:00 +0200
      Re: [PATCH v1 2/2] Mark functions with the __nocapture attribute "PaX Team" <pageexec@freemail.hu> - 2016-06-28 23:50 +0200
        Re: [PATCH v1 2/2] Mark functions with the __nocapture attribute Rasmus Villemoes <linux@rasmusvillemoes.dk> - 2016-06-29 00:50 +0200
      Re: [PATCH v1 2/2] Mark functions with the __nocapture attribute Emese Revfy <re.emese@gmail.com> - 2016-06-29 20:40 +0200
  Re: [PATCH v1 0/2] Introduce the initify gcc plugin Emese Revfy <re.emese@gmail.com> - 2016-06-28 13:40 +0200
  [PATCH v1 1/2] Add the initify gcc plugin Emese Revfy <re.emese@gmail.com> - 2016-06-28 13:40 +0200
    Re: [PATCH v1 1/2] Add the initify gcc plugin Rasmus Villemoes <linux@rasmusvillemoes.dk> - 2016-06-28 23:10 +0200
      Re: [PATCH v1 1/2] Add the initify gcc plugin Kees Cook <keescook@chromium.org> - 2016-06-29 17:00 +0200
      Re: [PATCH v1 1/2] Add the initify gcc plugin Emese Revfy <re.emese@gmail.com> - 2016-06-29 21:10 +0200
  Re: [kernel-hardening] [PATCH v1 0/2] Introduce the initify gcc  plugin Mark Rutland <mark.rutland@arm.com> - 2016-06-28 15:00 +0200
    Re: [kernel-hardening] [PATCH v1 0/2] Introduce the initify gcc  plugin Emese Revfy <re.emese@gmail.com> - 2016-06-28 18:10 +0200
      Re: [kernel-hardening] [PATCH v1 0/2] Introduce the initify gcc plugin Kees Cook <keescook@chromium.org> - 2016-06-28 22:50 +0200
        Re: [kernel-hardening] [PATCH v1 0/2] Introduce the initify gcc  plugin Mark Rutland <mark.rutland@arm.com> - 2016-06-29 10:30 +0200
          Re: [kernel-hardening] [PATCH v1 0/2] Introduce the initify gcc  plugin Mark Rutland <mark.rutland@arm.com> - 2016-06-29 20:00 +0200
            Re: [kernel-hardening] [PATCH v1 0/2] Introduce the initify gcc  plugin Emese Revfy <re.emese@gmail.com> - 2016-06-29 20:30 +0200
  Re: [PATCH v1 0/2] Introduce the initify gcc plugin Joe Perches <joe@perches.com> - 2016-06-28 18:40 +0200
    Re: [PATCH v1 0/2] Introduce the initify gcc plugin Joe Perches <joe@perches.com> - 2016-06-28 20:50 +0200
      Re: [PATCH v1 0/2] Introduce the initify gcc plugin Rasmus Villemoes <linux@rasmusvillemoes.dk> - 2016-06-28 21:10 +0200
        Re: [PATCH v1 0/2] Introduce the initify gcc plugin Emese Revfy <re.emese@gmail.com> - 2016-06-28 22:30 +0200
  Re: [PATCH v1 0/2] Introduce the initify gcc plugin Mathias Krause <minipli@ld-linux.so> - 2016-06-28 19:10 +0200
    Re: [PATCH v1 0/2] Introduce the initify gcc plugin Emese Revfy <re.emese@gmail.com> - 2016-06-28 22:30 +0200
  Re: [PATCH v1 0/2] Introduce the initify gcc plugin Joe Perches <joe@perches.com> - 2016-06-29 00:00 +0200
    Re: [kernel-hardening] Re: [PATCH v1 0/2] Introduce the initify gcc plugin Valdis.Kletnieks@vt.edu - 2016-06-29 00:10 +0200
      Re: [kernel-hardening] Re: [PATCH v1 0/2] Introduce the initify gcc  plugin Joe Perches <joe@perches.com> - 2016-06-29 02:00 +0200

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