Commit 1623a554 authored by Vasily Gorbik's avatar Vasily Gorbik
Browse files

s390/kexec: Disable stack protector in s390_reset_system() 



s390_reset_system() calls set_prefix(0), which switches back to the
absolute lowcore. At that point the stack protector canary no longer
matches the canary from the lowcore the function was entered with, so
the stack check fails.

Mark s390_reset_system() __no_stack_protector. This is safe here since
its callers (__do_machine_kdump() and __do_machine_kexec()) are
effectively no-return and fall back to disabled_wait() on failure.

Fixes: f5730d44 ("s390: Add stackprotector support")
Reported-by: default avatarNikita Dubrovskii <nikita@linux.ibm.com>
Reviewed-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Acked-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent 05c58a66

arch/s390/kernel/ipl.c

+1 −1
Original line number Diff line number Diff line
@@ -2377,7 +2377,7 @@ void __init setup_ipl(void) 
	atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb);

}



void s390_reset_system(void)

void __no_stack_protector s390_reset_system(void)

{

	/* Disable prefixing */

	set_prefix(0);