Re: [patch 01/18] powerpc: Move stack randomization after syscall_enter_from_user_mode()
Philippe Mathieu-Daudé <[email protected]>
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On 7/7/26 21:05, Thomas Gleixner wrote: > add_random_kstack_offset() is invoked before syscall_enter_from_user_mode() > establishes state. That's wrong because add_random_kstack_offset() calls > into instrumentable code. > > Move it after syscall_enter_from_user_mode() to ensure that state is > correctly established. > > Signed-off-by: Thomas Gleixner <[email protected]> > Cc: Michael Ellerman <[email protected]> > Cc: Shrikanth Hegde <[email protected]> > Cc: [email protected] > --- > arch/powerpc/kernel/syscall.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > --- a/arch/powerpc/kernel/syscall.c > +++ b/arch/powerpc/kernel/syscall.c > @@ -19,8 +19,8 @@ notrace long system_call_exception(struc > long ret; > syscall_fn f; > > - add_random_kstack_offset(); > r0 = syscall_enter_from_user_mode(regs, r0); > + add_random_kstack_offset(); > > if (unlikely(r0 >= NR_syscalls)) { > if (unlikely(trap_is_unsupported_scv(regs))) { > Reviewed-by: Philippe Mathieu-Daudé <[email protected]>