From mboxrd@z Thu Jan 1 00:00:00 1970 From: lauraa@codeaurora.org (Laura Abbott) Date: Tue, 01 Apr 2014 11:03:35 -0700 Subject: [PATCH] arm: don't allow CONFIG_DEBUG_SET_MODULE_RONX if CONFIG_JUMP_LABEL is enabled In-Reply-To: <1396346657-7166-1-git-send-email-holler@ahsoftware.de> References: <1396346657-7166-1-git-send-email-holler@ahsoftware.de> Message-ID: <533AFF77.5030106@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 4/1/2014 3:04 AM, Alexander Holler wrote: > CONFIG_DEBUG_SET_MODULE_RONX sounds like a nice security feature, but > things might fail late (and unexpected) if module code is set to read-only > while CONFIG_JUMP_LABEL is enabled (e.g. modprobe bridge). > > Avoid this. > > Signed-off-by: Alexander Holler > --- > arch/arm/Kconfig.debug | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug > index 0531da8..6627b9e 100644 > --- a/arch/arm/Kconfig.debug > +++ b/arch/arm/Kconfig.debug > @@ -1197,7 +1197,7 @@ config PID_IN_CONTEXTIDR > > config DEBUG_SET_MODULE_RONX > bool "Set loadable kernel module data as NX and text as RO" > - depends on MODULES > + depends on MODULES && !JUMP_LABEL > ---help--- > This option helps catch unintended modifications to loadable > kernel module's text and read-only data. It also prevents execution > Kees Cook has something similar[1] for not-module space as well, we probably want this there as well. A shame we keep finding reasons these features will be turned off. Looks good to me otherwise. Laura [1]http://lists.infradead.org/pipermail/linux-arm-kernel/2014-February/232644.html -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation