diff options
author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2017-11-24 16:23:15 +0100 |
---|---|---|
committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2017-11-24 16:37:01 +0100 |
commit | 345f8f34bb473241d62803951c18a844dd705f8d (patch) | |
tree | d1921973c63cdc100bafe94a83c70e892224ee1b | |
parent | fec37202e8a5c060e0c46cd353bf0b6d26b9cb02 (diff) |
s390: revert ELF_ET_DYN_BASE base changes
This reverts commit a73dc5370e153ac63718d850bddf0c9aa9d871e6.
Reducing the base address for 31-bit PIE executables from
(STACK_TOP/3)*2 to 4MB broke several compat programs which
use -fpie to move the executable out of the lower 16MB.
Cc: <stable@vger.kernel.org> # 4.13+
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
-rw-r--r-- | arch/s390/include/asm/elf.h | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/arch/s390/include/asm/elf.h b/arch/s390/include/asm/elf.h index 9a3cb3983c01..1a61b1b997f2 100644 --- a/arch/s390/include/asm/elf.h +++ b/arch/s390/include/asm/elf.h @@ -194,13 +194,14 @@ struct arch_elf_state { #define CORE_DUMP_USE_REGSET #define ELF_EXEC_PAGESIZE PAGE_SIZE -/* - * This is the base location for PIE (ET_DYN with INTERP) loads. On - * 64-bit, this is raised to 4GB to leave the entire 32-bit address - * space open for things that want to use the area for 32-bit pointers. - */ -#define ELF_ET_DYN_BASE (is_compat_task() ? 0x000400000UL : \ - 0x100000000UL) +/* 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. 64-bit + tasks are aligned to 4GB. */ +#define ELF_ET_DYN_BASE (is_compat_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. */ |