From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 403B936F917; Fri, 7 Aug 2026 13:54:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.156.1 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786110897; cv=none; b=swZGwhOv03nNp1tw3Ho86NrupRU95Fl0FBT/hrsMg5YO9ylEruE+J8bYgfXuMMrWoqyoZ6xpbxLuDPEejDHlIFvn1xZ1t8qAmu/Ro16VBku0DlSd2qfszGY9YH1/gU7/4GFRYejd+1TC4bD1f0y0L1/VzGVDE3WUyasQ1h/RuNM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786110897; c=relaxed/simple; bh=WBwK2un5KE8sVd5dx5UNDT3g7MHDaeQo9PiJQDovZGE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XDADplrCKVFayx1PVJx708NPKhirCkEnZKuCWiJYh+/vdSmU1lFmxgQk7hOihqbgQ31VPD2wZ3d0JGqfRfLdSIWci+RB6ow/4ErXMvhIqEOjKtFcqbVEea4sKE8ZNtWbnwD7J8ont7ro9ki6SXAiRcPiw1EL9Bgcv8zNBfz9xiE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com; spf=pass smtp.mailfrom=linux.ibm.com; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b=JsODq6Fy; arc=none smtp.client-ip=148.163.156.1 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="JsODq6Fy" Received: from pps.filterd (m0356517.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 677CllhC1514165; Fri, 7 Aug 2026 13:54:47 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:date:from:in-reply-to:message-id :mime-version:references:subject:to; s=pp1; bh=cYz8X6JhD/xoZOufW WFxDpFStL6bRVUjf0LZKO1QPZE=; b=JsODq6Fy3uMYG3nOaUaBk0qAr0xl8P6zR uADzmKRrfn9HKVF3aIZPFH+qQxBiy547TmVANqMLoxKFsPPfSP4V8+KuHra/NzHy zhqw5xVdvJ/Lw73CX3KUB6W+e9HR6s5TvulJy2OqcQoy9cT0uyWCLL5hGkk3gDIX yc0/HlUBF/Lx5/b92wpwPfbcexjnRAWVLSUncv/Trdk8m+U/epSFZvkB72klWXPF cUeysCAM9alVZQOkz6mqeIdG6IpJOYl0kIfDZtX3jzJaBS9PRs/kjBcf1jJ/gbIS HYf0/cmrNbj13j0O+ghgldI+x4xB+4cZZ9zDR6+G4rJ64RdjRxUow== Received: from ppma22.wdc07v.mail.ibm.com (5c.69.3da9.ip4.static.sl-reverse.com [169.61.105.92]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4fvxyyv63q-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 07 Aug 2026 13:54:46 +0000 (GMT) Received: from pps.filterd (ppma22.wdc07v.mail.ibm.com [127.0.0.1]) by ppma22.wdc07v.mail.ibm.com (8.18.1.7/8.18.1.7) with ESMTP id 677DQKcX013784; Fri, 7 Aug 2026 13:54:45 GMT Received: from smtprelay03.fra02v.mail.ibm.com ([9.218.2.224]) by ppma22.wdc07v.mail.ibm.com (PPS) with ESMTPS id 4fsugwg184-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 07 Aug 2026 13:54:45 +0000 (GMT) Received: from smtpav02.fra02v.mail.ibm.com (smtpav02.fra02v.mail.ibm.com [10.20.54.101]) by smtprelay03.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 677Dsff030867942 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 7 Aug 2026 13:54:41 GMT Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8765F2004E; Fri, 7 Aug 2026 13:54:41 +0000 (GMT) Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6545820043; Fri, 7 Aug 2026 13:54:41 +0000 (GMT) Received: from funtu2.ibm.com (unknown [9.111.146.84]) by smtpav02.fra02v.mail.ibm.com (Postfix) with ESMTP; Fri, 7 Aug 2026 13:54:41 +0000 (GMT) From: Harald Freudenberger To: dengler@linux.ibm.com, fcallies@linux.ibm.com, ifranzki@linux.ibm.com Cc: freude@linux.ibm.com, linux-s390@vger.kernel.org, Heiko Carstens , Vasily Gorbik , Alexander Gordeev , linux-crypto@vger.kernel.org Subject: [PATCH v3 3/3] s390/crypto: Rewrite AES ctr mode to be prepared for context analysis Date: Fri, 7 Aug 2026 15:54:40 +0200 Message-ID: <20260807135440.35888-4-freude@linux.ibm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260807135440.35888-1-freude@linux.ibm.com> References: <20260807135440.35888-1-freude@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Authority-Analysis: v=2.4 cv=SYrHsPRu c=1 sm=1 tr=0 ts=6a75e3a6 cx=c_pps a=5BHTudwdYE3Te8bg5FgnPg==:117 a=5BHTudwdYE3Te8bg5FgnPg==:17 a=Sv0fKeRqtYgA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=U7nrCbtTmkRpXpFmAIza:22 a=VnNF1IyMAAAA:8 a=e91DsxHqfR-orwYc_R4A:9 X-Proofpoint-Spam-Info: AW1haW4tMjYwODA3MDEwOCBTYWx0ZWRfX9Yvs8RrGa7RV t5M7keJes+ZEEIIx08sckcQKfpMQYENlITGIVpB/t2aG5YlFwzsl4yFMZI6VGPHmPH6AM17MJqZ 5Dz5E2y86QH4od29l7i2+DfL6e6gLhY= X-Proofpoint-ORIG-GUID: dnNd51RSBILM66zw_6cnCx65P8RF0rqh X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwODA3MDEwOCBTYWx0ZWRfX7YUSYYz5KKEW cVAnP71X/jN1w0n4b0zmB1yEA4YkHhpgb5HMWsm7/Pu8DJCcBo2lNeruH2jzvuh5Tn8jdbM7xyh kt8/3T11wokfIFPknvLuV+Aack9Vh5qPZ01+iCC1OC48YPXRPEtSVGOETDH+ooNRYN2sArHwLxG mKBJZmla1pszpVh8s73lIJV2TVr/LbnW3yDMQIw2CH7gDGeS9Sq8Ixbn+R8FPAQYjaBkLbtTqds JPbJ8hd4m3uPflUSYkQ4tmovxsD12eOg+/cGpFrWPBRxj31d+BBLyxeHMAwwmV+t0TRIvkYJISJ 9WWCXrd/mnOTFLzjG5pJQXtYJ9cWSUhR36HrNLbzfal508uQqGD2y/tGhYldfaXNXiv5ot/9vDt ET7UsGFkULZgOoCqIdVh+ojDqWWBBSoQxtCHQIlnQPZxawgDP6MMnFdA6KRQFIpDBaBNVVTfNY5 4X4tfb46FQbmQ2OUlDg== X-Proofpoint-GUID: dnNd51RSBILM66zw_6cnCx65P8RF0rqh X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-08-07_02,2026-08-06_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 malwarescore=0 priorityscore=1501 lowpriorityscore=0 suspectscore=0 bulkscore=0 impostorscore=0 phishscore=0 spamscore=0 adultscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2608070108 The AES ctr implementation produces a warning when used with clang and CONTEXT_ANALYIS enabled: arch/s390/crypto/aes_s390.c:585:13: warning: mutex 'ctrblk_lock' is not held on every path through here [-Wthread-safety-analysis] 585 | ctrptr = (n > AES_BLOCK_SIZE) ? ctrblk : walk.iv; | ^ arch/s390/crypto/aes_s390.c:577:11: note: mutex acquired here 577 | locked = mutex_trylock(&ctrblk_lock); | ^ Rewrite and reorganize the code such that the clang compiler's needs are fulfilled with keeping the compatibility, performance and correctness of the crypto algorithm. Signed-off-by: Harald Freudenberger Suggested-by: Heiko Carstens --- arch/s390/crypto/aes_s390.c | 60 +++++++++++++++++++++++-------------- 1 file changed, 38 insertions(+), 22 deletions(-) diff --git a/arch/s390/crypto/aes_s390.c b/arch/s390/crypto/aes_s390.c index 976f6f7257d5..e75f41e2bcb7 100644 --- a/arch/s390/crypto/aes_s390.c +++ b/arch/s390/crypto/aes_s390.c @@ -562,46 +562,62 @@ static unsigned int __ctrblk_init(u8 *ctrptr, u8 *iv, unsigned int nbytes) return n; } +static int __ctr_aes_crypt(struct s390_aes_ctx *sctx, + struct skcipher_walk *walk, bool locked) +{ + unsigned int n, nbytes; + int ret = 0; + u8 *ctrptr; + + while (!ret && ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE)) { + n = AES_BLOCK_SIZE; + if (nbytes >= 2 * AES_BLOCK_SIZE && locked) + n = __ctrblk_init(ctrblk, walk->iv, nbytes); + ctrptr = (n > AES_BLOCK_SIZE) ? ctrblk : walk->iv; + cpacf_kmctr(sctx->fc, sctx->key, walk->dst.virt.addr, + walk->src.virt.addr, n, ctrptr); + if (ctrptr == ctrblk) { + memcpy(walk->iv, ctrptr + n - AES_BLOCK_SIZE, + AES_BLOCK_SIZE); + } + crypto_inc(walk->iv, AES_BLOCK_SIZE); + ret = skcipher_walk_done(walk, nbytes - n); + } + + return ret; +} + static int ctr_aes_crypt(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm); - u8 buf[AES_BLOCK_SIZE], *ctrptr; struct skcipher_walk walk; - unsigned int n, nbytes; - int ret, locked; + u8 buf[AES_BLOCK_SIZE]; + int ret; if (unlikely(!sctx->fc)) return fallback_skcipher_crypt(sctx, req, 0); - locked = mutex_trylock(&ctrblk_lock); - ret = skcipher_walk_virt(&walk, req, false); - while (!ret && ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE)) { - n = AES_BLOCK_SIZE; + if (ret) + return ret; - if (nbytes >= 2*AES_BLOCK_SIZE && locked) - n = __ctrblk_init(ctrblk, walk.iv, nbytes); - ctrptr = (n > AES_BLOCK_SIZE) ? ctrblk : walk.iv; - cpacf_kmctr(sctx->fc, sctx->key, walk.dst.virt.addr, - walk.src.virt.addr, n, ctrptr); - if (ctrptr == ctrblk) - memcpy(walk.iv, ctrptr + n - AES_BLOCK_SIZE, - AES_BLOCK_SIZE); - crypto_inc(walk.iv, AES_BLOCK_SIZE); - ret = skcipher_walk_done(&walk, nbytes - n); - } - if (locked) + if (mutex_trylock(&ctrblk_lock)) { + ret = __ctr_aes_crypt(sctx, &walk, true); mutex_unlock(&ctrblk_lock); + } else { + ret = __ctr_aes_crypt(sctx, &walk, false); + } + /* * final block may be < AES_BLOCK_SIZE, copy only nbytes */ - if (!ret && nbytes) { + if (!ret && walk.nbytes) { memset(buf, 0, AES_BLOCK_SIZE); - memcpy(buf, walk.src.virt.addr, nbytes); + memcpy(buf, walk.src.virt.addr, walk.nbytes); cpacf_kmctr(sctx->fc, sctx->key, buf, buf, AES_BLOCK_SIZE, walk.iv); - memcpy(walk.dst.virt.addr, buf, nbytes); + memcpy(walk.dst.virt.addr, buf, walk.nbytes); crypto_inc(walk.iv, AES_BLOCK_SIZE); ret = skcipher_walk_done(&walk, 0); memzero_explicit(buf, sizeof(buf)); -- 2.43.0