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 X-Spam-Level: X-Spam-Status: No, score=-6.3 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88EB4C2BA15 for ; Fri, 3 Apr 2020 07:56:25 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5292020787 for ; Fri, 3 Apr 2020 07:56:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Z7h63Qkc" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5292020787 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linux-kernel-mentees-bounces@lists.linuxfoundation.org Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 2660688226; Fri, 3 Apr 2020 07:56:25 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id t52O+777SySZ; Fri, 3 Apr 2020 07:56:24 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by whitealder.osuosl.org (Postfix) with ESMTP id 8CA25881E8; Fri, 3 Apr 2020 07:56:24 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 81CBDC1831; Fri, 3 Apr 2020 07:56:24 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 036AEC07FF for ; Fri, 3 Apr 2020 07:56:24 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id E31C7890D5 for ; Fri, 3 Apr 2020 07:56:23 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id j-F+Nrv7nf4L for ; Fri, 3 Apr 2020 07:56:22 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail-pg1-f195.google.com (mail-pg1-f195.google.com [209.85.215.195]) by hemlock.osuosl.org (Postfix) with ESMTPS id DCACF88BA0 for ; Fri, 3 Apr 2020 07:56:22 +0000 (UTC) Received: by mail-pg1-f195.google.com with SMTP id r4so1672691pgg.4 for ; Fri, 03 Apr 2020 00:56:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=jGFgJcnAZcYkOmTi2e6KUvl6de/EYQat/43QjCkuwX0=; b=Z7h63QkcMcJIMchjnZ6OGIbR7pN+UWcQwA7SLkySnzrKirDCo6HDYjKLFj5gWEAnZ7 eNje8dyr5R8eU5fzk7yuvLwNKSfGuGmgXQcn5C74h+HP+PIlnunCyS5JlB1IpbAx2a2Z v+chsSP0JlFTG+TaEXCQhDNpOVcTHhJoPHwmmH2vcEtEF28W1QbcRpP6gXtOd1pxvvnC ei8R2TzjGijsRQB5iQHMXm9BaoqncW9navKH+Ca3GTgo1Wvp3wLJI82uQAJcZbxoDTWh o7f/VVcH8H1KrIuYuqLCXRUTmPFweG5l1KHN8uub4FEZoHXWgjoHr4s/zLTDj5fmmIHK 56Ew== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=jGFgJcnAZcYkOmTi2e6KUvl6de/EYQat/43QjCkuwX0=; b=rkO+FO0vN4IuQFPuS19k4C3yUnVU8xTzZS0SDWd53xeUl9KQChZKQfP5kOeXlgy3d0 UWd4sRncArkv5yCJXlyltBiw1ve7YXix9u+2i69bp0iKl9CjDiGB2x2SsqRvYwB2gBb7 uwxVjfjbBbQtsKE5yGL4ptuhqVmT+ybbpWcABsRGS1JYpEyuQv2ktd4/+PjxRap4lFL0 ACkr848onC2kqjMV8utyaSgpsiOazlT50qajRsmsdXTS0PwwvMmlwy0uxCYE1refO7qU oMZnB62bniMtaXY6xWSV6/tyGTVs0HS6iRCz2EsbXGte3XMCgcDB8rSiBR7pJG7nJaS9 HqGw== X-Gm-Message-State: AGi0PuYY6XxHa1pWFIrIuOWgtOBHc/T2kb565bcLs6/Zu+7xyG9pup5m f7amVfIthUcUiLH9QcX/Shw= X-Google-Smtp-Source: APiQypKtNPH46VRnJiamU928TrLfF1ef1udk+bsqM/kxdW3Cx6y1GHNcPLh23zVq5txnbater8/vkQ== X-Received: by 2002:aa7:999e:: with SMTP id k30mr7018349pfh.235.1585900582356; Fri, 03 Apr 2020 00:56:22 -0700 (PDT) Received: from workstation-portable ([103.87.56.98]) by smtp.gmail.com with ESMTPSA id g75sm5146054pje.37.2020.04.03.00.56.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Apr 2020 00:56:21 -0700 (PDT) Date: Fri, 3 Apr 2020 13:26:13 +0530 From: Amol Grover To: Paul Moore Message-ID: <20200403075613.GA2788@workstation-portable> References: <20200402055640.6677-1-frextrite@gmail.com> <20200402055640.6677-3-frextrite@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Cc: Juri Lelli , Peter Zijlstra , David Howells , Joel Fernandes , Vincent Guittot , James Morris , Madhuparna Bhowmik , Ingo Molnar , Mel Gorman , linux-kernel-mentees@lists.linuxfoundation.org, "Paul E . McKenney" , Jann Horn , Steven Rostedt , Shakeel Butt , Thomas Gleixner , Dietmar Eggemann , Ben Segall , linux-kernel@vger.kernel.org, Eric Paris , linux-audit@redhat.com, "Eric W . Biederman" , Andrew Morton Subject: Re: [Linux-kernel-mentees] [PATCH 3/3 RESEND] auditsc: Do not use RCU primitive to read from cred pointer X-BeenThere: linux-kernel-mentees@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-kernel-mentees-bounces@lists.linuxfoundation.org Sender: "Linux-kernel-mentees" On Thu, Apr 02, 2020 at 08:56:36AM -0400, Paul Moore wrote: > On Thu, Apr 2, 2020 at 1:57 AM Amol Grover wrote: > > task_struct::cred is only used task-synchronously and does > > not require any RCU locks, hence, rcu_dereference_check is > > not required to read from it. > > > > Suggested-by: Jann Horn > > Co-developed-by: Joel Fernandes (Google) > > Signed-off-by: Joel Fernandes (Google) > > Signed-off-by: Amol Grover > > --- > > kernel/auditsc.c | 15 +++++---------- > > 1 file changed, 5 insertions(+), 10 deletions(-) > > This is the exact same patch I ACK'd back in February, yes? > > https://lore.kernel.org/linux-audit/CAHC9VhQCbg1V290bYEZM+izDPRpr=XYXakohnDaMphkBBFgUaA@mail.gmail.com > Hi Paul, That's correct. I've resend the series out of the fear that the first 2 patches might've gotten lost as it's been almost a month since I last sent them. Could you please ack this again, and if you don't mind could you please go through the other 2 patches and ack them aswell? Thanks Amol > > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > > index 4effe01ebbe2..d3510513cdd1 100644 > > --- a/kernel/auditsc.c > > +++ b/kernel/auditsc.c > > @@ -430,24 +430,19 @@ static int audit_field_compare(struct task_struct *tsk, > > /* Determine if any context name data matches a rule's watch data */ > > /* Compare a task_struct with an audit_rule. Return 1 on match, 0 > > * otherwise. > > - * > > - * If task_creation is true, this is an explicit indication that we are > > - * filtering a task rule at task creation time. This and tsk == current are > > - * the only situations where tsk->cred may be accessed without an rcu read lock. > > */ > > static int audit_filter_rules(struct task_struct *tsk, > > struct audit_krule *rule, > > struct audit_context *ctx, > > struct audit_names *name, > > - enum audit_state *state, > > - bool task_creation) > > + enum audit_state *state) > > { > > const struct cred *cred; > > int i, need_sid = 1; > > u32 sid; > > unsigned int sessionid; > > > > - cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation); > > + cred = tsk->cred; > > > > for (i = 0; i < rule->field_count; i++) { > > struct audit_field *f = &rule->fields[i]; > > @@ -745,7 +740,7 @@ static enum audit_state audit_filter_task(struct task_struct *tsk, char **key) > > rcu_read_lock(); > > list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { > > if (audit_filter_rules(tsk, &e->rule, NULL, NULL, > > - &state, true)) { > > + &state)) { > > if (state == AUDIT_RECORD_CONTEXT) > > *key = kstrdup(e->rule.filterkey, GFP_ATOMIC); > > rcu_read_unlock(); > > @@ -791,7 +786,7 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk, > > list_for_each_entry_rcu(e, list, list) { > > if (audit_in_mask(&e->rule, ctx->major) && > > audit_filter_rules(tsk, &e->rule, ctx, NULL, > > - &state, false)) { > > + &state)) { > > rcu_read_unlock(); > > ctx->current_state = state; > > return state; > > @@ -815,7 +810,7 @@ static int audit_filter_inode_name(struct task_struct *tsk, > > > > list_for_each_entry_rcu(e, list, list) { > > if (audit_in_mask(&e->rule, ctx->major) && > > - audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) { > > + audit_filter_rules(tsk, &e->rule, ctx, n, &state)) { > > ctx->current_state = state; > > return 1; > > } > > -- > > 2.24.1 > > -- > paul moore > www.paul-moore.com _______________________________________________ Linux-kernel-mentees mailing list Linux-kernel-mentees@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees