On Sun, May 07, 2023 at 10:11:32AM +0200, Ard Biesheuvel wrote: > On Sun, 7 May 2023 at 07:11, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > > On Sat, May 06, 2023 at 02:34:33PM +0200, Ard Biesheuvel wrote: > > > All occurrences of the scs_load macro load the value of the shadow call > > > stack pointer from the task which is current at that point. So instead > > > of taking a task struct register argument in the scs_load macro to > > > specify the task struct to load from, let's always reference the current > > > task directly. This should make it much harder to exploit any > > > instruction sequences reloading the shadow call stack pointer register > > > from memory. > > > > > > Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> > > > Acked-by: Mark Rutland <mark.rutland@xxxxxxx> > > > Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> > > > Link: https://lore.kernel.org/r/20230109174800.3286265-2-ardb@xxxxxxxxxx > > > Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> > > > Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> > > > --- > > > arch/arm64/include/asm/scs.h | 7 ++++--- > > > arch/arm64/kernel/entry.S | 4 ++-- > > > arch/arm64/kernel/head.S | 2 +- > > > 3 files changed, 7 insertions(+), 6 deletions(-) > > > > What is the git commit id of this in Linus's tree? > > > > commit 2198d07c509f1db4a1185d1f65aaada794c6ea59 upstream. Thanks, both now queued up! greg k-h
