From: Alexander Popov Date: Thu, 16 Aug 2018 22:17:02 +0000 (+0300) Subject: doc: self-protection: Add information about STACKLEAK feature X-Git-Tag: v4.20-rc1~34^2~2 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=ed535a2dae1836d15c71e250475952881265d244;p=linux.git doc: self-protection: Add information about STACKLEAK feature Add information about STACKLEAK feature to the "Memory poisoning" section of self-protection.rst. Signed-off-by: Alexander Popov Signed-off-by: Kees Cook --- diff --git a/Documentation/security/self-protection.rst b/Documentation/security/self-protection.rst index e1ca698e0006..f584fb74b4ff 100644 --- a/Documentation/security/self-protection.rst +++ b/Documentation/security/self-protection.rst @@ -302,11 +302,11 @@ sure structure holes are cleared. Memory poisoning ---------------- -When releasing memory, it is best to poison the contents (clear stack on -syscall return, wipe heap memory on a free), to avoid reuse attacks that -rely on the old contents of memory. This frustrates many uninitialized -variable attacks, stack content exposures, heap content exposures, and -use-after-free attacks. +When releasing memory, it is best to poison the contents, to avoid reuse +attacks that rely on the old contents of memory. E.g., clear stack on a +syscall return (``CONFIG_GCC_PLUGIN_STACKLEAK``), wipe heap memory on a +free. This frustrates many uninitialized variable attacks, stack content +exposures, heap content exposures, and use-after-free attacks. Destination tracking --------------------