Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752070AbaKFOie (ORCPT ); Thu, 6 Nov 2014 09:38:34 -0500 Received: from mail-wg0-f42.google.com ([74.125.82.42]:43408 "EHLO mail-wg0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751685AbaKFOiX (ORCPT ); Thu, 6 Nov 2014 09:38:23 -0500 From: Daniel Thompson To: Jason Wessel Cc: Daniel Thompson , kgdb-bugreport@lists.sourceforge.net, linux-kernel@vger.kernel.org, Andrew Morton , Greg Kroah-Hartman , Jiri Slaby , Steven Rostedt , Frederic Weisbecker , Ingo Molnar , Colin Cross , kernel-team@android.com, patches@linaro.org, linaro-kernel@lists.linaro.org, John Stultz , Sumit Semwal , Anton Vorontsov Subject: [RESEND PATCH v5 3.18-rc3 8/8] kdb: Allow access to sensitive commands to be restricted by default Date: Thu, 6 Nov 2014 14:36:47 +0000 Message-Id: <1415284607-7628-9-git-send-email-daniel.thompson@linaro.org> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1415284607-7628-1-git-send-email-daniel.thompson@linaro.org> References: <1415284607-7628-1-git-send-email-daniel.thompson@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently kiosk mode must be explicitly requested by the bootloader or userspace. It is convenient to be able to change the default value in a similar manner to CONFIG_MAGIC_SYSRQ_DEFAULT_MASK. Signed-off-by: Daniel Thompson Cc: Jason Wessel --- kernel/debug/kdb/kdb_main.c | 2 +- lib/Kconfig.kgdb | 25 +++++++++++++++++++++++++ 2 files changed, 26 insertions(+), 1 deletion(-) diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index fe1ac56..8d84979 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -47,7 +47,7 @@ #undef MODULE_PARAM_PREFIX #define MODULE_PARAM_PREFIX "kdb." -static int kdb_cmd_enabled; +static int kdb_cmd_enabled = CONFIG_KDB_DEFAULT_ENABLE; module_param_named(cmd_enable, kdb_cmd_enabled, int, 0600); #define GREP_LEN 256 diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb index 358eb81..c635a10 100644 --- a/lib/Kconfig.kgdb +++ b/lib/Kconfig.kgdb @@ -73,6 +73,31 @@ config KGDB_KDB help KDB frontend for kernel +config KDB_DEFAULT_ENABLE + hex "KDB: Select kdb command functions to be enabled by default" + depends on KGDB_KDB + default 0x1 + help + Specifiers which kdb commands are enabled by default. This may + be set to 1 or 0 to enable all commands or disable almost all + commands. + + Alternatively the following bitmask applies: + + 0x0002 - allow arbitrary reads from memory and symbol lookup + 0x0004 - allow arbitrary writes to memory + 0x0008 - allow current register state to be inspected + 0x0010 - allow current register state to be modified + 0x0020 - allow passive inspection (backtrace, process list, lsmod) + 0x0040 - allow flow control management (breakpoint, single step) + 0x0080 - enable signalling of processes + 0x0100 - allow machine to be rebooted + + The config option merely sets the default at boot time. Both + issuing 'echo X > /sys/module/kdb/parameters/cmd_enable' or + setting with kdb.cmd_enable=X kernel command line option will + override the default settings. + config KDB_KEYBOARD bool "KGDB_KDB: keyboard as input device" depends on VT && KGDB_KDB -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/