From mboxrd@z Thu Jan 1 00:00:00 1970 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 us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 ADB97C433EF for ; Tue, 14 Dec 2021 18:23:58 +0000 (UTC) Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-381-19GNFuwMOD-rhTVBlcJUCw-1; Tue, 14 Dec 2021 13:23:54 -0500 X-MC-Unique: 19GNFuwMOD-rhTVBlcJUCw-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id CFC571853053; Tue, 14 Dec 2021 18:23:48 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B85D27A4AB; Tue, 14 Dec 2021 18:23:48 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 90F5F1806D1D; Tue, 14 Dec 2021 18:23:48 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 1BEI56tM027881 for ; Tue, 14 Dec 2021 13:05:06 -0500 Received: by smtp.corp.redhat.com (Postfix) id C03CE401E47; Tue, 14 Dec 2021 18:05:06 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast02.extmail.prod.ext.rdu2.redhat.com [10.11.55.18]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B9ABB401DB0 for ; Tue, 14 Dec 2021 18:05:06 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [205.139.110.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4156680234F for ; Tue, 14 Dec 2021 18:05:06 +0000 (UTC) Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-464-7wc7oJosOb67lVGJT3Xg5A-1; Tue, 14 Dec 2021 13:05:02 -0500 X-MC-Unique: 7wc7oJosOb67lVGJT3Xg5A-1 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D9A636164C; Tue, 14 Dec 2021 18:05:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7DD9DC34600; Tue, 14 Dec 2021 18:04:59 +0000 (UTC) Date: Tue, 14 Dec 2021 12:10:40 -0600 From: "Gustavo A. R. Silva" To: Xiu Jianfeng Subject: Re: [PATCH -next] audit: use struct_size() helper in kmalloc() Message-ID: <20211214181040.GA13575@embeddedor> References: <20211214114854.133328-1-xiujianfeng@huawei.com> <20211214175448.GA13107@embeddedor> MIME-Version: 1.0 In-Reply-To: <20211214175448.GA13107@embeddedor> X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 2.85 on 10.11.54.10 X-loop: linux-audit@redhat.com X-Mailman-Approved-At: Tue, 14 Dec 2021 13:23:34 -0500 Cc: linux-kernel@vger.kernel.org, eparis@redhat.com, "Gustavo A. R. Silva" , wangweiyang2@huawei.com, linux-audit@redhat.com, linux-hardening@vger.kernel.org X-BeenThere: linux-audit@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: Linux Audit Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-audit-bounces@redhat.com Errors-To: linux-audit-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=linux-audit-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Tue, Dec 14, 2021 at 11:54:48AM -0600, Gustavo A. R. Silva wrote: > On Tue, Dec 14, 2021 at 07:48:54PM +0800, Xiu Jianfeng wrote: > > Make use of struct_size() helper instead of an open-coded calucation. > > > > Link: https://github.com/KSPP/linux/issues/160 > > Signed-off-by: Xiu Jianfeng > > --- > > kernel/audit.c | 2 +- > > kernel/audit_tree.c | 2 +- > > kernel/auditfilter.c | 2 +- > > 3 files changed, 3 insertions(+), 3 deletions(-) > > > > diff --git a/kernel/audit.c b/kernel/audit.c > > index d4084751cfe6..f33028578c60 100644 > > --- a/kernel/audit.c > > +++ b/kernel/audit.c This could use struct_size(), too: 1461 audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0, 1462 sig_data, sizeof(*sig_data) + len); > > @@ -1446,7 +1446,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) > > if (err) > > return err; > > } > > - sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL); > > + sig_data = kmalloc(struct_size(sig_data, ctx, len), GFP_KERNEL); > > if (!sig_data) { > > if (audit_sig_sid) > > security_release_secctx(ctx, len); > > diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c > > index 72324afcffef..e7315d487163 100644 > > --- a/kernel/audit_tree.c > > +++ b/kernel/audit_tree.c > > @@ -94,7 +94,7 @@ static struct audit_tree *alloc_tree(const char *s) > > { > > struct audit_tree *tree; > > > > - tree = kmalloc(sizeof(struct audit_tree) + strlen(s) + 1, GFP_KERNEL); > > + tree = kmalloc(struct_size(tree, pathname, strlen(s) + 1), GFP_KERNEL); > > if (tree) { > > refcount_set(&tree->count, 1); > > tree->goner = 0; > > diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c > > index 4173e771650c..19352820b274 100644 > > --- a/kernel/auditfilter.c > > +++ b/kernel/auditfilter.c Also, in this same file the following piece of code could use struct_size(), too: 1093 skb = audit_make_reply(seq, AUDIT_LIST_RULES, 0, 1, 1094 data, 1095 sizeof(*data) + data->buflen); Thanks -- Gustavo > > @@ -637,7 +637,7 @@ static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule) > > void *bufp; > > int i; > > > > - data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL); > > + data = kmalloc(struct_size(data, buf, krule->buflen), GFP_KERNEL); > > Why don't you also transform the zero-length array in struct > audit_rule_data into a flexible-array member: > > 508 struct audit_rule_data { > 509 __u32 flags; /* AUDIT_PER_{TASK,CALL}, AUDIT_PREPEND */ > 510 __u32 action; /* AUDIT_NEVER, AUDIT_POSSIBLE, AUDIT_ALWAYS */ > 511 __u32 field_count; > 512 __u32 mask[AUDIT_BITMASK_SIZE]; /* syscall(s) affected */ > 513 __u32 fields[AUDIT_MAX_FIELDS]; > 514 __u32 values[AUDIT_MAX_FIELDS]; > 515 __u32 fieldflags[AUDIT_MAX_FIELDS]; > 516 __u32 buflen; /* total length of string fields */ > 517 char buf[0]; /* string fields buffer */ > 518 }; > > Thanks > -- > Gustavo > > > if (unlikely(!data)) > > return NULL; > > memset(data, 0, sizeof(*data)); > > -- > > 2.17.1 > > > > > > > > -- Linux-audit mailing list Linux-audit@redhat.com https://listman.redhat.com/mailman/listinfo/linux-audit