From 526b4af47f44148c9d665e57723ed9f86634c6e3 Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Thu, 26 May 2011 12:26:24 +0200 Subject: ACPI: Split out custom_method functionality into an own driver With /sys/kernel/debug/acpi/custom_method root can write to arbitrary memory and increase his priveleges, even if these are restricted. -> Make this an own debug .config option and warn about the security issue in the config description. -> Still keep acpi/debugfs.c which now only creates an empty /sys/kernel/debug/acpi directory. There might be other users of it later. Signed-off-by: Thomas Renninger Acked-by: Rafael J. Wysocki Acked-by: rui.zhang@intel.com Signed-off-by: Len Brown --- Documentation/acpi/method-customizing.txt | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'Documentation/acpi') diff --git a/Documentation/acpi/method-customizing.txt b/Documentation/acpi/method-customizing.txt index 3e1d25aee3f..5f55373dd53 100644 --- a/Documentation/acpi/method-customizing.txt +++ b/Documentation/acpi/method-customizing.txt @@ -66,3 +66,8 @@ Note: We can use a kernel with multiple custom ACPI method running, But each individual write to debugfs can implement a SINGLE method override. i.e. if we want to insert/override multiple ACPI methods, we need to redo step c) ~ g) for multiple times. + +Note: Be aware that root can mis-use this driver to modify arbitrary + memory and gain additional rights, if root's privileges got + restricted (for example if root is not allowed to load additional + modules after boot). -- cgit v1.2.3-70-g09d2