From ad84112a1135bda928806fcbb98680847ab81436 Mon Sep 17 00:00:00 2001 From: Cyrille Pitchen Date: Mon, 8 Feb 2016 16:26:49 +0100 Subject: [PATCH] crypto: atmel-sha - fix race in atmel_sha_final() When (!ctx->bufcnt && !(ctx->flags & SHA_FLAGS_PAD)), the former source code used to set the SHA_FLAGS_BUSY without checking whether this flag was already set. If so, the hardware is already processing another hash request so the processing of the req argument of atmel_sha_final() should be delayed by queueing this request, the same way as done for the (ctx->bufcnt != 0) case. Signed-off-by: Cyrille Pitchen Signed-off-by: Herbert Xu --- drivers/crypto/atmel-sha.c | 24 ++---------------------- 1 file changed, 2 insertions(+), 22 deletions(-) diff --git a/drivers/crypto/atmel-sha.c b/drivers/crypto/atmel-sha.c index e4757f8..7b93586 100644 --- a/drivers/crypto/atmel-sha.c +++ b/drivers/crypto/atmel-sha.c @@ -979,37 +979,17 @@ static int atmel_sha_update(struct ahash_request *req) static int atmel_sha_final(struct ahash_request *req) { struct atmel_sha_reqctx *ctx = ahash_request_ctx(req); - struct atmel_sha_ctx *tctx = crypto_tfm_ctx(req->base.tfm); - struct atmel_sha_dev *dd = tctx->dd; - - int err = 0; ctx->flags |= SHA_FLAGS_FINUP; if (ctx->flags & SHA_FLAGS_ERROR) return 0; /* uncompleted hash is not needed */ - if (ctx->bufcnt) { - return atmel_sha_enqueue(req, SHA_OP_FINAL); - } else if (!(ctx->flags & SHA_FLAGS_PAD)) { /* add padding */ - err = atmel_sha_hw_init(dd); - if (err) - goto err1; - - dd->req = req; - dd->flags |= SHA_FLAGS_BUSY; - err = atmel_sha_final_req(dd); - } else { + if (ctx->flags & SHA_FLAGS_PAD) /* copy ready hash (+ finalize hmac) */ return atmel_sha_finish(req); - } - -err1: - if (err != -EINPROGRESS) - /* done_task will not finish it, so do it here */ - atmel_sha_finish_req(req, err); - return err; + return atmel_sha_enqueue(req, SHA_OP_FINAL); } static int atmel_sha_finup(struct ahash_request *req) -- 2.7.4