Commit a22a2316 authored by Eric Biggers's avatar Eric Biggers Committed by Herbert Xu
Browse files

crypto: skcipher - remove redundant clamping to page size 



In the case where skcipher_walk_next() allocates a bounce page, that
page by definition has size PAGE_SIZE.  The number of bytes to copy 'n'
is guaranteed to fit in it, since earlier in the function it was clamped
to be at most a page.  Therefore remove the unnecessary logic that tried
to clamp 'n' again to fit in the bounce page.

Signed-off-by: default avatarEric Biggers <ebiggers@google.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 807c8018

crypto/skcipher.c

+1 −5
Original line number Diff line number Diff line
@@ -250,6 +250,7 @@ static int skcipher_walk_next(struct skcipher_walk *walk) 
slow_path:

		return skcipher_next_slow(walk, bsize);

	}

	walk->nbytes = n;



	if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) {

		if (!walk->page) {
@@ -259,15 +260,10 @@ static int skcipher_walk_next(struct skcipher_walk *walk) 
			if (!walk->page)

				goto slow_path;

		}



		walk->nbytes = min_t(unsigned, n,

				     PAGE_SIZE - offset_in_page(walk->page));

		walk->flags |= SKCIPHER_WALK_COPY;

		return skcipher_next_copy(walk);

	}



	walk->nbytes = n;



	return skcipher_next_fast(walk);

}