From owner-svn-src-head@freebsd.org  Sat Mar 25 10:47:36 2017
Return-Path: <owner-svn-src-head@freebsd.org>
Delivered-To: svn-src-head@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id D3986D1C7CF;
 Sat, 25 Mar 2017 10:47:36 +0000 (UTC) (envelope-from kib@FreeBSD.org)
Received: from repo.freebsd.org (repo.freebsd.org
 [IPv6:2610:1c1:1:6068::e6a:0])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (Client did not present a certificate)
 by mx1.freebsd.org (Postfix) with ESMTPS id A348A1EE7;
 Sat, 25 Mar 2017 10:47:36 +0000 (UTC) (envelope-from kib@FreeBSD.org)
Received: from repo.freebsd.org ([127.0.1.37])
 by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id v2PAlZLN035032;
 Sat, 25 Mar 2017 10:47:35 GMT (envelope-from kib@FreeBSD.org)
Received: (from kib@localhost)
 by repo.freebsd.org (8.15.2/8.15.2/Submit) id v2PAlZHx035031;
 Sat, 25 Mar 2017 10:47:35 GMT (envelope-from kib@FreeBSD.org)
Message-Id: <201703251047.v2PAlZHx035031@repo.freebsd.org>
X-Authentication-Warning: repo.freebsd.org: kib set sender to kib@FreeBSD.org
 using -f
From: Konstantin Belousov <kib@FreeBSD.org>
Date: Sat, 25 Mar 2017 10:47:35 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
 svn-src-head@freebsd.org
Subject: svn commit: r315934 - head/sys/x86/iommu
X-SVN-Group: head
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
X-BeenThere: svn-src-head@freebsd.org
X-Mailman-Version: 2.1.23
Precedence: list
List-Id: SVN commit messages for the src tree for head/-current
 <svn-src-head.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-head/>
List-Post: <mailto:svn-src-head@freebsd.org>
List-Help: <mailto:svn-src-head-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sat, 25 Mar 2017 10:47:36 -0000

Author: kib
Date: Sat Mar 25 10:47:35 2017
New Revision: 315934
URL: https://svnweb.freebsd.org/changeset/base/315934

Log:
  Avoid leaking allocated but unused context after creation race.
  
  As noted in the comment, nothing special needs to be done to destroy
  the unneeded context after the allocation race, but the context memory
  itself still should to be freed.
  
  Sponsored by:	The FreeBSD Foundation
  MFC after:	1 week

Modified:
  head/sys/x86/iommu/intel_ctx.c

Modified: head/sys/x86/iommu/intel_ctx.c
==============================================================================
--- head/sys/x86/iommu/intel_ctx.c	Sat Mar 25 10:45:16 2017	(r315933)
+++ head/sys/x86/iommu/intel_ctx.c	Sat Mar 25 10:47:35 2017	(r315934)
@@ -472,13 +472,15 @@ dmar_get_ctx_for_dev(struct dmar_unit *d
 			    dmar->unit, dmar->segment, bus, slot,
 			    func, rid, domain->domain, domain->mgaw,
 			    domain->agaw, id_mapped ? "id" : "re");
+			dmar_unmap_pgtbl(sf);
 		} else {
-			/* Nothing needs to be done to destroy ctx1. */
+			dmar_unmap_pgtbl(sf);
 			dmar_domain_destroy(domain1);
+			/* Nothing needs to be done to destroy ctx1. */
+			free(ctx1, M_DMAR_CTX);
 			domain = ctx->domain;
 			ctx->refs++; /* tag referenced us */
 		}
-		dmar_unmap_pgtbl(sf);
 	} else {
 		domain = ctx->domain;
 		ctx->refs++; /* tag referenced us */