On Wed, Nov 13, 2019 at 10:25:16AM -0800, Kees Cook wrote: > In order to avoid CFI function prototype mismatches, this removes the > casts on assembly implementations of sha1/256/512 accelerators. The > safety checks from BUILD_BUG_ON() remain. > > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> > --- > arch/x86/crypto/sha1_ssse3_glue.c | 61 ++++++++++++----------------- > arch/x86/crypto/sha256_ssse3_glue.c | 31 +++++++-------- > arch/x86/crypto/sha512_ssse3_glue.c | 28 ++++++------- > 3 files changed, 50 insertions(+), 70 deletions(-) > > diff --git a/arch/x86/crypto/sha1_ssse3_glue.c b/arch/x86/crypto/sha1_ssse3_glue.c > index 639d4c2fd6a8..a151d899f37a 100644 > --- a/arch/x86/crypto/sha1_ssse3_glue.c > +++ b/arch/x86/crypto/sha1_ssse3_glue.c > @@ -27,11 +27,8 @@ > #include <crypto/sha1_base.h> > #include <asm/simd.h> > > -typedef void (sha1_transform_fn)(u32 *digest, const char *data, > - unsigned int rounds); > - > static int sha1_update(struct shash_desc *desc, const u8 *data, > - unsigned int len, sha1_transform_fn *sha1_xform) > + unsigned int len, sha1_block_fn *sha1_xform) > { > struct sha1_state *sctx = shash_desc_ctx(desc); > > @@ -39,48 +36,44 @@ static int sha1_update(struct shash_desc *desc, const u8 *data, > (sctx->count % SHA1_BLOCK_SIZE) + len < SHA1_BLOCK_SIZE) > return crypto_sha1_update(desc, data, len); > > - /* make sure casting to sha1_block_fn() is safe */ > + /* make sure sha1_block_fn() use in generic routines is safe */ > BUILD_BUG_ON(offsetof(struct sha1_state, state) != 0); This update to the comment makes no sense, since sha1_block_fn() is obviously safe in the helpers, and this says nothing about the assembly functions. Instead this should say something like: /* * Make sure that struct sha1_state begins directly with the 160-bit * SHA1 internal state, as this is what the assembly functions expect. */ Likewise for SHA-256 and SHA-512, except for those it would be a 256-bit and 512-bit internal state respectively. > -asmlinkage void sha1_transform_ssse3(u32 *digest, const char *data, > - unsigned int rounds); > +asmlinkage void sha1_transform_ssse3(struct sha1_state *digest, > + u8 const *data, int rounds); 'u8 const' is unconventional. Please use 'const u8' instead. Also, this function prototype is also given in a comment in the corresponding assembly file. Can you please update that too, and also leave a comment in the assembly file like "struct sha1_state is assumed to begin with u32 state[5]."? Likewise for all the other SHA-1, and SHA-256, and SHA-512 assembly functions, except it would be u32 state[8] for SHA-256 and u64 state[8] for SHA-512. - Eric