Currently get_sigframe() checks only (ka->sa.sa_flags & SA_ONSTACK) && (!on_sig_stack(sp)) to determine whether the switch to sigaltstack is needed. It forgets to checks whether the sigaltstack was previously set.
This patch replaces the !on_sig_stack(sp) with the standard check sas_ss_flags(sp) == 0 that takes into account both conditions: it succeeds only if the sigaltstack is enabled but currently not active. CC: Andy Lutomirski <[email protected]> CC: [email protected] CC: Chen Liqin <[email protected]> CC: Lennox Wu <[email protected]> CC: Michael Ellerman <[email protected]> CC: Andrew Morton <[email protected]> CC: James Hogan <[email protected]> Signed-off-by: Stas Sergeev <[email protected]> --- arch/score/kernel/signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/score/kernel/signal.c b/arch/score/kernel/signal.c index e381c8c..bd1c7c8 100644 --- a/arch/score/kernel/signal.c +++ b/arch/score/kernel/signal.c @@ -127,7 +127,7 @@ static void __user *get_sigframe(struct k_sigaction *ka, sp -= 32; /* This is the X/Open sanctioned signal stack switching. */ - if ((ka->sa.sa_flags & SA_ONSTACK) && (!on_sig_stack(sp))) + if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags(sp) == 0)) sp = current->sas_ss_sp + current->sas_ss_size; return (void __user*)((sp - frame_size) & ~7); -- 2.5.0
