Message ID | 1391115944-10183-1-git-send-email-lauraa@codeaurora.org (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On Thu, Jan 30, 2014 at 1:05 PM, Laura Abbott <lauraa@codeaurora.org> wrote: > arm64 currently lacks support for -fstack-protector. Add > similar functionality to arm to detect stack corruption. > > Cc: Will Deacon <will.deacon@arm.com> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Thanks! Acked-by: Kees Cook <keescook@chromium.org> -Kees
On Fri, Jan 31, 2014 at 2:50 PM, Kees Cook <keescook@chromium.org> wrote: > On Thu, Jan 30, 2014 at 1:05 PM, Laura Abbott <lauraa@codeaurora.org> wrote: >> arm64 currently lacks support for -fstack-protector. Add >> similar functionality to arm to detect stack corruption. >> >> Cc: Will Deacon <will.deacon@arm.com> >> Cc: Catalin Marinas <catalin.marinas@arm.com> >> Signed-off-by: Laura Abbott <lauraa@codeaurora.org> > > Thanks! > > Acked-by: Kees Cook <keescook@chromium.org> Hi again, This patch never got applied any where. Who can take this? Thanks! -Kees
On Wed, Jun 25, 2014 at 01:24:05AM +0100, Kees Cook wrote: > On Fri, Jan 31, 2014 at 2:50 PM, Kees Cook <keescook@chromium.org> wrote: > > On Thu, Jan 30, 2014 at 1:05 PM, Laura Abbott <lauraa@codeaurora.org> wrote: > >> arm64 currently lacks support for -fstack-protector. Add > >> similar functionality to arm to detect stack corruption. > >> > >> Cc: Will Deacon <will.deacon@arm.com> > >> Cc: Catalin Marinas <catalin.marinas@arm.com> > >> Signed-off-by: Laura Abbott <lauraa@codeaurora.org> > > > > Thanks! > > > > Acked-by: Kees Cook <keescook@chromium.org> > > Hi again, > > This patch never got applied any where. Who can take this? We can take this via the arm64 tree. Laura, is the patch still valid against current mainline? Will
On 6/25/2014 1:38 AM, Will Deacon wrote: > On Wed, Jun 25, 2014 at 01:24:05AM +0100, Kees Cook wrote: >> On Fri, Jan 31, 2014 at 2:50 PM, Kees Cook <keescook@chromium.org> wrote: >>> On Thu, Jan 30, 2014 at 1:05 PM, Laura Abbott <lauraa@codeaurora.org> wrote: >>>> arm64 currently lacks support for -fstack-protector. Add >>>> similar functionality to arm to detect stack corruption. >>>> >>>> Cc: Will Deacon <will.deacon@arm.com> >>>> Cc: Catalin Marinas <catalin.marinas@arm.com> >>>> Signed-off-by: Laura Abbott <lauraa@codeaurora.org> >>> >>> Thanks! >>> >>> Acked-by: Kees Cook <keescook@chromium.org> >> >> Hi again, >> >> This patch never got applied any where. Who can take this? > > We can take this via the arm64 tree. Laura, is the patch still valid against > current mainline? > Apparently not. I will send out a rebased version. Thanks, Laura
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index dd4327f..2ebf522 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -27,6 +27,7 @@ config ARM64 select HARDIRQS_SW_RESEND select HAVE_ARCH_JUMP_LABEL select HAVE_ARCH_TRACEHOOK + select HAVE_CC_STACKPROTECTOR select HAVE_DEBUG_BUGVERBOSE select HAVE_DEBUG_KMEMLEAK select HAVE_DMA_API_DEBUG diff --git a/arch/arm64/include/asm/stackprotector.h b/arch/arm64/include/asm/stackprotector.h new file mode 100644 index 0000000..fe5e287 --- /dev/null +++ b/arch/arm64/include/asm/stackprotector.h @@ -0,0 +1,38 @@ +/* + * GCC stack protector support. + * + * Stack protector works by putting predefined pattern at the start of + * the stack frame and verifying that it hasn't been overwritten when + * returning from the function. The pattern is called stack canary + * and gcc expects it to be defined by a global variable called + * "__stack_chk_guard" on ARM. This unfortunately means that on SMP + * we cannot have a different canary value per task. + */ + +#ifndef __ASM_STACKPROTECTOR_H +#define __ASM_STACKPROTECTOR_H + +#include <linux/random.h> +#include <linux/version.h> + +extern unsigned long __stack_chk_guard; + +/* + * Initialize the stackprotector canary value. + * + * NOTE: this must only be called from functions that never return, + * and it must always be inlined. + */ +static __always_inline void boot_init_stack_canary(void) +{ + unsigned long canary; + + /* Try to get a semi random initial value. */ + get_random_bytes(&canary, sizeof(canary)); + canary ^= LINUX_VERSION_CODE; + + current->stack_canary = canary; + __stack_chk_guard = current->stack_canary; +} + +#endif /* _ASM_STACKPROTECTOR_H */ diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 1e5a178..89c301d 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -50,6 +50,12 @@ #include <asm/processor.h> #include <asm/stacktrace.h> +#ifdef CONFIG_CC_STACKPROTECTOR +#include <linux/stackprotector.h> +unsigned long __stack_chk_guard __read_mostly; +EXPORT_SYMBOL(__stack_chk_guard); +#endif + static void setup_restart(void) { /*
arm64 currently lacks support for -fstack-protector. Add similar functionality to arm to detect stack corruption. Cc: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Laura Abbott <lauraa@codeaurora.org> --- I realized today that the patch I gave before was not going to work for recent trees because of changes to CC_STACKPROTECTOR that were not in my working tree before. This should be the patch to actually work against recent kernels. --- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/stackprotector.h | 38 +++++++++++++++++++++++++++++++ arch/arm64/kernel/process.c | 6 +++++ 3 files changed, 45 insertions(+), 0 deletions(-) create mode 100644 arch/arm64/include/asm/stackprotector.h