crypto: hash - Fix handling of unaligned buffers

The correct way to calculate the start of the aligned part of an
unaligned buffer is:

  offset = ALIGN(offset, alignmask + 1);

However, crypto_hash_walk_done() has:

  offset += alignmask - 1;
  offset = ALIGN(offset, alignmask + 1);

which actually skips a whole block unless offset % (alignmask + 1) == 1.

This patch fixes the problem.

Signed-off-by: Szilveszter Ördög <slipszi@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/ahash.c b/crypto/ahash.c
index 33a4ff4..b8c59b8 100644 (file)
--- a/crypto/ahash.c
+++ b/crypto/ahash.c
@@ -78,7 +78,6 @@ int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
        walk->data -= walk->offset;
 
        if (nbytes && walk->offset & alignmask && !err) {
-               walk->offset += alignmask - 1;
                walk->offset = ALIGN(walk->offset, alignmask + 1);
                walk->data += walk->offset;