From c6f5b001e65cdac592b65a08c5d2dd179cfba568 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 14 Apr 2015 15:48:04 -0700 Subject: s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE In preparation for moving ET_DYN randomization into the ELF loader (which requires a static ELF_ET_DYN_BASE), this redefines s390's existing ET_DYN randomization in a call to arch_mmap_rnd(). This refactoring results in the same ET_DYN randomization on s390. Signed-off-by: Kees Cook Acked-by: Martin Schwidefsky Cc: Heiko Carstens Reviewed-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/include/asm/elf.h | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'arch/s390/include/asm/elf.h') diff --git a/arch/s390/include/asm/elf.h b/arch/s390/include/asm/elf.h index c9c875d9ed31..f8db4781a4c2 100644 --- a/arch/s390/include/asm/elf.h +++ b/arch/s390/include/asm/elf.h @@ -161,10 +161,12 @@ extern unsigned int vdso_enabled; /* This is the location that an ET_DYN program is loaded if exec'ed. Typical use of this is to invoke "./ld.so someprog" to test out a new version of the loader. We need to make sure that it is out of the way of the program - that it will "exec", and that there is sufficient room for the brk. */ - + that it will "exec", and that there is sufficient room for the brk. 64-bit + tasks are aligned to 4GB. */ extern unsigned long randomize_et_dyn(void); -#define ELF_ET_DYN_BASE randomize_et_dyn() +#define ELF_ET_DYN_BASE (randomize_et_dyn() + (is_32bit_task() ? \ + (STACK_TOP / 3 * 2) : \ + (STACK_TOP / 3 * 2) & ~((1UL << 32) - 1))) /* This yields a mask that user programs can use to figure out what instruction set this CPU supports. */ -- cgit v1.2.3