[RFC PATCH v3 18/20] x86: Add types to indirectly called assembly functions

From: Sami Tolvanen
Date: Fri Jun 10 2022 - 19:37:34 EST


With CONFIG_CFI_CLANG, assembly functions indirectly called from C code
must be annotated with type identifiers to pass CFI checking. Add types
to indirectly called functions.

Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
arch/x86/crypto/blowfish-x86_64-asm_64.S | 5 +++--
arch/x86/lib/memcpy_64.S | 3 ++-
2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/arch/x86/crypto/blowfish-x86_64-asm_64.S b/arch/x86/crypto/blowfish-x86_64-asm_64.S
index 802d71582689..4a43e072d2d1 100644
--- a/arch/x86/crypto/blowfish-x86_64-asm_64.S
+++ b/arch/x86/crypto/blowfish-x86_64-asm_64.S
@@ -6,6 +6,7 @@
*/

#include <linux/linkage.h>
+#include <linux/cfi_types.h>

.file "blowfish-x86_64-asm.S"
.text
@@ -141,7 +142,7 @@ SYM_FUNC_START(__blowfish_enc_blk)
RET;
SYM_FUNC_END(__blowfish_enc_blk)

-SYM_FUNC_START(blowfish_dec_blk)
+SYM_TYPED_FUNC_START(blowfish_dec_blk)
/* input:
* %rdi: ctx
* %rsi: dst
@@ -332,7 +333,7 @@ SYM_FUNC_START(__blowfish_enc_blk_4way)
RET;
SYM_FUNC_END(__blowfish_enc_blk_4way)

-SYM_FUNC_START(blowfish_dec_blk_4way)
+SYM_TYPED_FUNC_START(blowfish_dec_blk_4way)
/* input:
* %rdi: ctx
* %rsi: dst
diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S
index d0d7b9bc6cad..e5d9b299577f 100644
--- a/arch/x86/lib/memcpy_64.S
+++ b/arch/x86/lib/memcpy_64.S
@@ -2,6 +2,7 @@
/* Copyright 2002 Andi Kleen */

#include <linux/linkage.h>
+#include <linux/cfi_types.h>
#include <asm/errno.h>
#include <asm/cpufeatures.h>
#include <asm/alternative.h>
@@ -27,7 +28,7 @@
* Output:
* rax original destination
*/
-SYM_FUNC_START(__memcpy)
+__SYM_TYPED_FUNC_START(__memcpy, memcpy)
ALTERNATIVE_2 "jmp memcpy_orig", "", X86_FEATURE_REP_GOOD, \
"jmp memcpy_erms", X86_FEATURE_ERMS

--
2.36.1.476.g0c4daa206d-goog