ARM: Ensure predictable endian state on signal handler entry

commit 53399053eb505cf541b2405bd9d9bca5ecfb96fb upstream.

Ensure a predictable endian state when entering signal handlers.  This
avoids programs which use SETEND to momentarily switch their endian
state from having their signal handlers entered with an unpredictable
endian state.

Acked-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index ef2f86a5e78a2965e0de4c9b9815c23a8e0baf63..dcf60d7c3a19c9f560f6e0a6e50121d7cd586686 100644 (file)
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -410,7 +410,9 @@ setup_return(struct pt_regs *regs, struct k_sigaction *ka,
        unsigned long handler = (unsigned long)ka->sa.sa_handler;
        unsigned long retcode;
        int thumb = 0;
-       unsigned long cpsr = regs->ARM_cpsr & ~PSR_f;
+       unsigned long cpsr = regs->ARM_cpsr & ~(PSR_f | PSR_E_BIT);
+
+       cpsr |= PSR_ENDSTATE;
 
        /*
         * Maybe we need to deliver a 32-bit signal to a 26-bit task.