From patchwork Fri Jun 21 16:59:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Biggers X-Patchwork-Id: 13707917 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 68ECBC27C4F for ; Fri, 21 Jun 2024 17:00:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Cnmqj5pAoqjf/QCY6i58nG3LxV12shiLj4oC8mmE3e8=; b=dFHnwVVx/jYmxOMPK0D1BUBpOb 98vjZz9R5+OzupAE3kbrKr3OI9/tpXyeeVRAHSEfA3pOs1lHMJreX9arugwB8P8NK3pG4wvCCWVXe zRPnVo+iaucmQ+EKtftv9BwMUlEjvdzQDrkFfoSL7r98UDCuMe1dztPiqsdyFJ/YUAD+zIzyCz15P qfEa70Dbi6jlUHVNAicv+8zhUdxLNluVpB05BcbNkd6UbvN8k0vRuOBul6QRIFdrmNv8P93aVbbAU piZj6OLVpOY7R4pOV+9jNdtACt2YmZ2++fOL5HbbqunE4K2/79bubD5LrA/4VgGmGNfrGrAIHSLRI t2YOhrYA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sKhck-0000000A1f0-3uV6; Fri, 21 Jun 2024 17:00:30 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sKhcX-0000000A1VB-3vhf for linux-arm-kernel@lists.infradead.org; Fri, 21 Jun 2024 17:00:19 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 2A63D62B61; Fri, 21 Jun 2024 17:00:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 76F91C4AF0A; Fri, 21 Jun 2024 17:00:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718989216; bh=6USdTOOyYM3FNFIuW1a3O/WfkiZlhPxeGJEgqz38Sgw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=O8PuJMKnPBgqE3pbF/On9Owe+WUuzNwk0hDGwJXOtQrMk5mBHXQV6/1S7KKFuAbTr ncV0uRvdKzPyfDvDs6z48a9acujSdMvHZhr2oAjGGUIvlnfWBMMUD0F5+LvBbuIWJi 127sxDcxkVhi2InXsKt39C2RKrKedcoyG6LKB2Rj+4PihsopUgeF4aGdH93h3wUj+1 vhgZxWK1axYT0huzF2/TKVXk0LFo0ovupCFQikNVaDg+n0IatuunwEbytW5eAhlpXk iobRLpyA8y3shjRfpXqDGGcXYCnoP1XBAuaV1LLZ+trjiOiXbf2fcHdCzbFZwRDfKP ogECHWVRCV18w== From: Eric Biggers To: linux-crypto@vger.kernel.org, fsverity@lists.linux.dev, dm-devel@lists.linux.dev Cc: x86@kernel.org, linux-arm-kernel@lists.infradead.org, Ard Biesheuvel , Sami Tolvanen , Bart Van Assche , Herbert Xu , Alasdair Kergon , Mike Snitzer , Mikulas Patocka Subject: [PATCH v6 02/15] crypto: testmgr - generate power-of-2 lengths more often Date: Fri, 21 Jun 2024 09:59:09 -0700 Message-ID: <20240621165922.77672-3-ebiggers@kernel.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240621165922.77672-1-ebiggers@kernel.org> References: <20240621165922.77672-1-ebiggers@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240621_100018_124788_C97073E9 X-CRM114-Status: GOOD ( 13.14 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Eric Biggers Implementations of hash functions often have special cases when lengths are a multiple of the hash function's internal block size (e.g. 64 for SHA-256, 128 for SHA-512). Currently, when the fuzz testing code generates lengths, it doesn't prefer any length mod 64 over any other. This limits the coverage of these special cases. Therefore, this patch updates the fuzz testing code to generate power-of-2 lengths and divide messages exactly in half a bit more often. Reviewed-by: Sami Tolvanen Acked-by: Ard Biesheuvel Signed-off-by: Eric Biggers --- crypto/testmgr.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/crypto/testmgr.c b/crypto/testmgr.c index a780b615f8c6..f02cb075bd68 100644 --- a/crypto/testmgr.c +++ b/crypto/testmgr.c @@ -914,18 +914,24 @@ static unsigned int generate_random_length(struct rnd_state *rng, { unsigned int len = prandom_u32_below(rng, max_len + 1); switch (prandom_u32_below(rng, 4)) { case 0: - return len % 64; + len %= 64; + break; case 1: - return len % 256; + len %= 256; + break; case 2: - return len % 1024; + len %= 1024; + break; default: - return len; + break; } + if (len && prandom_u32_below(rng, 4) == 0) + len = rounddown_pow_of_two(len); + return len; } /* Flip a random bit in the given nonempty data buffer */ static void flip_random_bit(struct rnd_state *rng, u8 *buf, size_t size) { @@ -1017,10 +1023,12 @@ static char *generate_random_sgl_divisions(struct rnd_state *rng, unsigned int this_len; const char *flushtype_str; if (div == &divs[max_divs - 1] || prandom_bool(rng)) this_len = remaining; + else if (prandom_u32_below(rng, 4) == 0) + this_len = (remaining + 1) / 2; else this_len = prandom_u32_inclusive(rng, 1, remaining); div->proportion_of_total = this_len; if (prandom_u32_below(rng, 4) == 0)