2020-05-02 18:30:22

by Eric Biggers

[permalink] [raw]
Subject: [PATCH 2/7] crypto: powerpc/sha1 - remove unused temporary workspace

From: Eric Biggers <[email protected]>

The PowerPC implementation of SHA-1 doesn't actually use the 16-word
temporary array that's passed to the assembly code. This was probably
meant to correspond to the 'W' array that lib/sha1.c uses. However, in
sha1-powerpc-asm.S these values are actually stored in GPRs 16-31.

Referencing SHA_WORKSPACE_WORDS from this code also isn't appropriate,
since it's an implementation detail of lib/sha1.c.

Therefore, just remove this unneeded array.

Tested with:

export ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
make mpc85xx_defconfig
cat >> .config << EOF
# CONFIG_MODULES is not set
# CONFIG_CRYPTO_MANAGER_DISABLE_TESTS is not set
CONFIG_DEBUG_KERNEL=y
CONFIG_CRYPTO_MANAGER_EXTRA_TESTS=y
CONFIG_CRYPTO_SHA1_PPC=y
EOF
make olddefconfig
make -j32
qemu-system-ppc -M mpc8544ds -cpu e500 -nographic \
-kernel arch/powerpc/boot/zImage \
-append "cryptomgr.fuzz_iterations=1000 cryptomgr.panic_on_fail=1"

Cc: [email protected]
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Paul Mackerras <[email protected]>
Signed-off-by: Eric Biggers <[email protected]>
---
arch/powerpc/crypto/sha1.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/crypto/sha1.c b/arch/powerpc/crypto/sha1.c
index 7b43fc352089b1..db46b6130a9642 100644
--- a/arch/powerpc/crypto/sha1.c
+++ b/arch/powerpc/crypto/sha1.c
@@ -16,12 +16,11 @@
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
-#include <linux/cryptohash.h>
#include <linux/types.h>
#include <crypto/sha.h>
#include <asm/byteorder.h>

-extern void powerpc_sha_transform(u32 *state, const u8 *src, u32 *temp);
+void powerpc_sha_transform(u32 *state, const u8 *src);

static int sha1_init(struct shash_desc *desc)
{
@@ -47,7 +46,6 @@ static int sha1_update(struct shash_desc *desc, const u8 *data,
src = data;

if ((partial + len) > 63) {
- u32 temp[SHA_WORKSPACE_WORDS];

if (partial) {
done = -partial;
@@ -56,12 +54,11 @@ static int sha1_update(struct shash_desc *desc, const u8 *data,
}

do {
- powerpc_sha_transform(sctx->state, src, temp);
+ powerpc_sha_transform(sctx->state, src);
done += 64;
src = data + done;
} while (done + 63 < len);

- memzero_explicit(temp, sizeof(temp));
partial = 0;
}
memcpy(sctx->buffer + partial, src, len - done);
--
2.26.2