[PATCH v6 kspp-next 08/22] Make sure ORC lookup covers the entire _etext - _stext

Alexander Lobakin
2021-08-31T14:42:31Z

From: Kristen Carlson Accardi <kristen@linux.intel.com>

When using -ffunction-sections to place each function in
it's own text section so it can be randomized at load time, the
linker will place most of the functions into separate .text.*
sections. SIZEOF(.text) won't work here for calculating the ORC
lookup table size, the total text size must be calculated to
include .text AND all .text.*.

Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
[ alobakin: move it to vmlinux.lds.h and make arch-indep ]
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
---
include/asm-generic/vmlinux.lds.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 5d6da19b02bc..01fdeb5dd216 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -887,10 +887,11 @@
KEEP(*(.orc_unwind)) \
__stop_orc_unwind = .; \
} \
+ text_size = _etext - _stext; \
. = ALIGN(4); \
.orc_lookup : AT(ADDR(.orc_lookup) - LOAD_OFFSET) { \
orc_lookup = .; \
- . += (((SIZEOF(.text) + LOOKUP_BLOCK_SIZE - 1) / \
+ . += (((text_size + LOOKUP_BLOCK_SIZE - 1) / \
LOOKUP_BLOCK_SIZE) + 1) * 4; \
orc_lookup_end = .; \
}
--
2.31.1