[PATCH] crypto: arm/sha1 - Fix clang function cast warnings

[Herbert Xu]

On Thu, Dec 08, 2022 at 07:05:45PM +0100, Ard Biesheuvel wrote:
>
> We can, as the BUILD_BUG() will catch it if struct sha1_state gets
> modified in an incompatible way.

Thanks for confirming!

---8<---
Instead of casting the function which upsets clang for some reason,
change the assembly function siganture instead.

Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>

diff --git a/arch/arm/crypto/sha1_glue.c b/arch/arm/crypto/sha1_glue.c
index 6c2b849e459d..95a727bcd664 100644
--- a/arch/arm/crypto/sha1_glue.c
+++ b/arch/arm/crypto/sha1_glue.c
@@ -21,31 +21,29 @@
 
 #include "sha1.h"
 
-asmlinkage void sha1_block_data_order(u32 *digest,
-		const unsigned char *data, unsigned int rounds);
+asmlinkage void sha1_block_data_order(struct sha1_state *digest,
+		const u8 *data, int rounds);
 
 int sha1_update_arm(struct shash_desc *desc, const u8 *data,
 		    unsigned int len)
 {
-	/* make sure casting to sha1_block_fn() is safe */
+	/* make sure signature matches sha1_block_fn() */
 	BUILD_BUG_ON(offsetof(struct sha1_state, state) != 0);
 
-	return sha1_base_do_update(desc, data, len,
-				   (sha1_block_fn *)sha1_block_data_order);
+	return sha1_base_do_update(desc, data, len, sha1_block_data_order);
 }
 EXPORT_SYMBOL_GPL(sha1_update_arm);
 
 static int sha1_final(struct shash_desc *desc, u8 *out)
 {
-	sha1_base_do_finalize(desc, (sha1_block_fn *)sha1_block_data_order);
+	sha1_base_do_finalize(desc, sha1_block_data_order);
 	return sha1_base_finish(desc, out);
 }
 
 int sha1_finup_arm(struct shash_desc *desc, const u8 *data,
 		   unsigned int len, u8 *out)
 {
-	sha1_base_do_update(desc, data, len,
-			    (sha1_block_fn *)sha1_block_data_order);
+	sha1_base_do_update(desc, data, len, sha1_block_data_order);
 	return sha1_final(desc, out);
 }
 EXPORT_SYMBOL_GPL(sha1_finup_arm);
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt