[PATCH v2 10/12] crypto: arm64/sm3 - fix possible crash with CFI enabled

Eric Biggers ebiggers at kernel.org
Fri Nov 18 11:44:19 PST 2022


From: Eric Biggers <ebiggers at google.com>

sm3_neon_transform() is called via indirect function calls.  Therefore
it needs to use SYM_TYPED_FUNC_START instead of SYM_FUNC_START to cause
its type hash to be emitted when the kernel is built with
CONFIG_CFI_CLANG=y.  Otherwise, the code crashes with a CFI failure (if
the compiler didn't happen to optimize out the indirect call).

Fixes: c50d32859e70 ("arm64: Add types to indirect called assembly functions")
Acked-by: Peter Zijlstra (Intel) <peterz at infradead.org>
Reviewed-by: Sami Tolvanen <samitolvanen at google.com>
Signed-off-by: Eric Biggers <ebiggers at google.com>
---
 arch/arm64/crypto/sm3-neon-core.S | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/crypto/sm3-neon-core.S b/arch/arm64/crypto/sm3-neon-core.S
index 3e3b4e5c736fc..4357e0e51be38 100644
--- a/arch/arm64/crypto/sm3-neon-core.S
+++ b/arch/arm64/crypto/sm3-neon-core.S
@@ -9,6 +9,7 @@
  */
 
 #include <linux/linkage.h>
+#include <linux/cfi_types.h>
 #include <asm/assembler.h>
 
 /* Context structure */
@@ -351,7 +352,7 @@
 	 */
 	.text
 .align 3
-SYM_FUNC_START(sm3_neon_transform)
+SYM_TYPED_FUNC_START(sm3_neon_transform)
 	ldp		ra, rb, [RSTATE, #0]
 	ldp		rc, rd, [RSTATE, #8]
 	ldp		re, rf, [RSTATE, #16]
-- 
2.38.1




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