Hi, I don't think these should be applied to -mm. They would normally go via my hardening tree (with other gcc plugins), but also Mark is going to be spinning a v2... -Kees On Tue, Apr 26, 2022 at 01:51:41PM -0700, Andrew Morton wrote: > > The patch titled > Subject: arm64: entry: use stackleak_erase_on_task_stack() > has been added to the -mm tree. Its filename is > arm64-entry-use-stackleak_erase_on_task_stack.patch > > This patch should soon appear at > https://ozlabs.org/~akpm/mmots/broken-out/arm64-entry-use-stackleak_erase_on_task_stack.patch > and later at > https://ozlabs.org/~akpm/mmotm/broken-out/arm64-entry-use-stackleak_erase_on_task_stack.patch > > Before you just go and hit "reply", please: > a) Consider who else should be cc'ed > b) Prefer to cc a suitable mailing list as well > c) Ideally: find the original patch on the mailing list and do a > reply-to-all to that, adding suitable additional cc's > > *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** > > The -mm tree is included into linux-next and is updated > there every 3-4 working days > > ------------------------------------------------------ > From: Mark Rutland <mark.rutland@xxxxxxx> > Subject: arm64: entry: use stackleak_erase_on_task_stack() > > On arm64 we always call stackleak_erase() on a task stack, and never call > it on another stack. We can avoid some redundant work by using > stackleak_erase_on_task_stack(), telling the stackleak code that it's > being called on a task stack. > > Link: https://lkml.kernel.org/r/20220425115603.781311-9-mark.rutland@xxxxxxx > Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx> > Cc: Alexander Popov <alex.popov@xxxxxxxxx> > Cc: Andy Lutomirski <luto@xxxxxxxxxx> > Cc: Catalin Marinas <catalin.marinas@xxxxxxx> > Cc: Kees Cook <keescook@xxxxxxxxxxxx> > Cc: Will Deacon <will@xxxxxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > --- > > arch/arm64/kernel/entry.S | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > --- a/arch/arm64/kernel/entry.S~arm64-entry-use-stackleak_erase_on_task_stack > +++ a/arch/arm64/kernel/entry.S > @@ -596,7 +596,7 @@ SYM_CODE_START_LOCAL(ret_to_user) > ldr x19, [tsk, #TSK_TI_FLAGS] // re-check for single-step > enable_step_tsk x19, x2 > #ifdef CONFIG_GCC_PLUGIN_STACKLEAK > - bl stackleak_erase > + bl stackleak_erase_on_task_stack > #endif > kernel_exit 0 > SYM_CODE_END(ret_to_user) > _ > > Patches currently in -mm which might be from mark.rutland@xxxxxxx are > > arm64-stackleak-fix-current_top_of_stack.patch > stackleak-move-skip_erasing-check-earlier.patch > stackleak-rework-stack-low-bound-handling.patch > stackleak-clarify-variable-names.patch > stackleak-rework-stack-high-bound-handling.patch > stackleak-remove-redundant-check.patch > stackleak-add-on-off-stack-variants.patch > arm64-entry-use-stackleak_erase_on_task_stack.patch > -- Kees Cook
