From patchwork Wed Jun 14 23:27:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 108198 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:994d:0:b0:3d9:f83d:47d9 with SMTP id k13csp289488vqr; Wed, 14 Jun 2023 16:35:26 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ6FMCew73pMsdR9DAzVeBpWXvWIK/UOB/CsKZWvhRfMLauYIljTGaGTT3zGxV9cWE3Yo7g5 X-Received: by 2002:a17:907:1c97:b0:973:ff4d:d01e with SMTP id nb23-20020a1709071c9700b00973ff4dd01emr18129157ejc.31.1686785726338; Wed, 14 Jun 2023 16:35:26 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1686785726; cv=none; d=google.com; s=arc-20160816; b=J2T3RfDze82yO1x/oFap6QDzXDMGpYtMZh9S3kOm7U6yzPPW7flpt5jTwXKH4fOmeF 7NSWzIB+PBVDtz5RW5XbRiPGvTpevBW4uF5Yo3gHNnK9dwKMxquIItAJfK8FCUc5rkAf SyKf5/g3Seu5RKYRU0oksZDfRoTVItWDeoqutsZWu2rY6HEAHoESTt/PeNcOXSYLH5JW d1sTsMfLBX1xoFuGYBkzGVbNUgKcUHggcbGC3sH9K861Do7z2jSeHeg0b4r15ymLwrEw dDkak1oLzcd21T7R6ddVRrXCai++A4NB5Yl195RPe8oW2xEx2GvmKzr9Ufd/5gS85VZV EAIw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:message-id:date:from:content-transfer-encoding :content-id:mime-version:subject:cc:to:organization:dkim-signature; bh=aH8zwLa8Ht2nXaE8fo3wqv7zLHm1tw4+70R/cDKjh3s=; b=YIa3qfYa65yEMU1h52kc7JXbPPM6OMFRIr5YhYhIdcT3M5jKHRY8M8EEcaRgB0ghGu z1OGqmUqJjmFoqEuQ5lEUn9+tt2ciXBw26RRSXtpdsjhFzlRXMkjDYAHpdqa1uKHC8fY 2Ez0k2XkF5fI3oFxCa1k7AMOpARJGxqOozxw3yW7ZdlQRZNCYiHGi6hrUYKiKJA4i8DE Td1q6DLzNvup0RnJbEa1yHd+AltfzaG3TMS2MfV3qDfF0a5YxAMoq0N47kpXbLNBVUfg 62EF8HMmnUnGA1f8iBfNGU9q9gAtMkD9f0w1LXsRB5iMW66V8fT042Z0NhtzALF2OAsy wd1A== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=Pib7553m; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id n4-20020a17090625c400b00974e7637ea3si8053130ejb.702.2023.06.14.16.35.02; Wed, 14 Jun 2023 16:35:26 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=Pib7553m; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235533AbjFNX2x (ORCPT + 99 others); Wed, 14 Jun 2023 19:28:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59840 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229516AbjFNX2v (ORCPT ); Wed, 14 Jun 2023 19:28:51 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AB1571FD7 for ; Wed, 14 Jun 2023 16:28:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1686785280; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=aH8zwLa8Ht2nXaE8fo3wqv7zLHm1tw4+70R/cDKjh3s=; b=Pib7553m97gLDb/s0E3V+7jCoW58jZS1t2ygyRC3W7QMAac1p0Sq5dX/2Dl2zYWSUouRHl y6nssujR7lIzBoi4HSx69+yp+7uUIAEugKCZzc1pZlqRo0ix07AtEinXcrul7CHlH7RP4N LsA5s3QmdWxiYniv6S3TZ9b4qMWeA1s= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-85-n6p0z6GaO3ei54QFL73rZQ-1; Wed, 14 Jun 2023 19:27:56 -0400 X-MC-Unique: n6p0z6GaO3ei54QFL73rZQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 1504A296A603; Wed, 14 Jun 2023 23:27:56 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.42.28.67]) by smtp.corp.redhat.com (Postfix) with ESMTP id 559E240C6F5E; Wed, 14 Jun 2023 23:27:54 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 To: netdev@vger.kernel.org cc: dhowells@redhat.com, syzbot+13a08c0bf4d212766c3c@syzkaller.appspotmail.com, syzbot+14234ccf6d0ef629ec1a@syzkaller.appspotmail.com, syzbot+4e2e47f32607d0f72d43@syzkaller.appspotmail.com, syzbot+472626bb5e7c59fb768f@syzkaller.appspotmail.com, Herbert Xu , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jens Axboe , Matthew Wilcox , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH net-next] crypto: af_alg/hash: Fix recvmsg() after sendmsg(MSG_MORE) MIME-Version: 1.0 Content-ID: <1679811.1686785244.1@warthog.procyon.org.uk> From: David Howells Date: Thu, 15 Jun 2023 00:27:53 +0100 Message-ID: <1679829.1686785273@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1768723029709760524?= X-GMAIL-MSGID: =?utf-8?q?1768723029709760524?= If an AF_ALG socket bound to a hashing algorithm is sent a zero-length message with MSG_MORE set and then recvmsg() is called without first sending another message without MSG_MORE set to end the operation, an oops will occur because the crypto context and result doesn't now get set up in advance because hash_sendmsg() now defers that as long as possible in the hope that it can use crypto_ahash_digest() - and then because the message is zero-length, it the data wrangling loop is skipped. Fix this by always making a pass of the loop, even in the case that no data is provided to the sendmsg(). Fix also extract_iter_to_sg() to handle a zero-length iterator by returning 0 immediately. Whilst we're at it, remove the code to create a kvmalloc'd scatterlist if we get more than ALG_MAX_PAGES - this shouldn't happen. Fixes: c662b043cdca ("crypto: af_alg/hash: Support MSG_SPLICE_PAGES") Reported-by: syzbot+13a08c0bf4d212766c3c@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/000000000000b928f705fdeb873a@google.com/ Reported-by: syzbot+14234ccf6d0ef629ec1a@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/000000000000c047db05fdeb8790@google.com/ Reported-by: syzbot+4e2e47f32607d0f72d43@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/000000000000bcca3205fdeb87fb@google.com/ Reported-by: syzbot+472626bb5e7c59fb768f@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/000000000000b55d8805fdeb8385@google.com/ Signed-off-by: David Howells Tested-by: syzbot+13a08c0bf4d212766c3c@syzkaller.appspotmail.com Tested-by: syzbot+14234ccf6d0ef629ec1a@syzkaller.appspotmail.com Tested-by: syzbot+4e2e47f32607d0f72d43@syzkaller.appspotmail.com Tested-by: syzbot+472626bb5e7c59fb768f@syzkaller.appspotmail.com cc: Herbert Xu cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: Jens Axboe cc: Matthew Wilcox cc: linux-crypto@vger.kernel.org cc: netdev@vger.kernel.org Acked-by: Herbert Xu --- crypto/algif_hash.c | 21 +++++---------------- lib/scatterlist.c | 2 +- 2 files changed, 6 insertions(+), 17 deletions(-) diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c index dfb048cefb60..1176533a55c9 100644 --- a/crypto/algif_hash.c +++ b/crypto/algif_hash.c @@ -83,26 +83,14 @@ static int hash_sendmsg(struct socket *sock, struct msghdr *msg, ctx->more = false; - while (msg_data_left(msg)) { + do { ctx->sgl.sgt.sgl = ctx->sgl.sgl; ctx->sgl.sgt.nents = 0; ctx->sgl.sgt.orig_nents = 0; err = -EIO; npages = iov_iter_npages(&msg->msg_iter, max_pages); - if (npages == 0) - goto unlock_free; - - if (npages > ARRAY_SIZE(ctx->sgl.sgl)) { - err = -ENOMEM; - ctx->sgl.sgt.sgl = - kvmalloc(array_size(npages, - sizeof(*ctx->sgl.sgt.sgl)), - GFP_KERNEL); - if (!ctx->sgl.sgt.sgl) - goto unlock_free; - } - sg_init_table(ctx->sgl.sgl, npages); + sg_init_table(ctx->sgl.sgl, max_t(size_t, npages, 1)); ctx->sgl.need_unpin = iov_iter_extract_will_pin(&msg->msg_iter); @@ -111,7 +99,8 @@ static int hash_sendmsg(struct socket *sock, struct msghdr *msg, if (err < 0) goto unlock_free; len = err; - sg_mark_end(ctx->sgl.sgt.sgl + ctx->sgl.sgt.nents - 1); + if (len > 0) + sg_mark_end(ctx->sgl.sgt.sgl + ctx->sgl.sgt.nents - 1); if (!msg_data_left(msg)) { err = hash_alloc_result(sk, ctx); @@ -148,7 +137,7 @@ static int hash_sendmsg(struct socket *sock, struct msghdr *msg, copied += len; af_alg_free_sg(&ctx->sgl); - } + } while (msg_data_left(msg)); ctx->more = msg->msg_flags & MSG_MORE; err = 0; diff --git a/lib/scatterlist.c b/lib/scatterlist.c index e97d7060329e..77a7b18ee751 100644 --- a/lib/scatterlist.c +++ b/lib/scatterlist.c @@ -1340,7 +1340,7 @@ ssize_t extract_iter_to_sg(struct iov_iter *iter, size_t maxsize, struct sg_table *sgtable, unsigned int sg_max, iov_iter_extraction_t extraction_flags) { - if (maxsize == 0) + if (!maxsize || !iter->count) return 0; switch (iov_iter_type(iter)) {