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From: Kees Cook <keescook@chromium.org>
To: Jiri Kosina <jikos@kernel.org>
Cc: Kees Cook <keescook@chromium.org>,
	Geert Uytterhoeven <geert@linux-m68k.org>,
	Thomas Gleixner <tglx@linutronix.de>,
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Subject: [PATCH 0/2] Adjust brk randomness
Date: Fri, 16 Feb 2024 22:25:42 -0800
Message-Id: <20240217062035.work.493-kees@kernel.org>
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Hi,

It was recently pointed out[1] that x86_64 brk entropy was not great,
and that on all architectures the brk can (when the random offset is 0)
be immediately adjacent to .bss, leaving no gap that could stop linear
overflows from the .bss. Address both issues.

-Kees

Link: https://lore.kernel.org/linux-hardening/CA+2EKTVLvc8hDZc+2Yhwmus=dzOUG5E4gV7ayCbu0MPJTZzWkw@mail.gmail.com [1]

Kees Cook (2):
  x86: Increase brk randomness entropy on x86_64
  binfmt_elf: Leave a gap between .bss and brk

 arch/x86/kernel/process.c | 5 ++++-
 fs/binfmt_elf.c           | 3 +++
 2 files changed, 7 insertions(+), 1 deletion(-)

-- 
2.34.1