[PATCH v2 03/29] crypto: skcipher - remove redundant clamping to page size
From: Eric Biggers <ebiggers@kernel.org>
Date: 2024-12-30 00:16:00
Also in:
linux-crypto, lkml
Subsystem:
crypto api, the rest · Maintainers:
Herbert Xu, "David S. Miller", Linus Torvalds
From: Eric Biggers <redacted> 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: Eric Biggers <redacted> --- crypto/skcipher.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/crypto/skcipher.c b/crypto/skcipher.c
index 887cbce8f78d..c627e267b125 100644
--- a/crypto/skcipher.c
+++ b/crypto/skcipher.c@@ -248,28 +248,24 @@ static int skcipher_walk_next(struct skcipher_walk *walk) return skcipher_walk_done(walk, -EINVAL); slow_path: return skcipher_next_slow(walk, bsize); } + walk->nbytes = n; if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) { if (!walk->page) { gfp_t gfp = skcipher_walk_gfp(walk); walk->page = (void *)__get_free_page(gfp); 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); } static int skcipher_copy_iv(struct skcipher_walk *walk) {
--
2.47.1