From owner-svn-src-all@freebsd.org Tue Dec 13 18:05:15 2016 Return-Path: Delivered-To: svn-src-all@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 47D8FC765C0; Tue, 13 Dec 2016 18:05:15 +0000 (UTC) (envelope-from bdrewery@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 174A3F7A; Tue, 13 Dec 2016 18:05:15 +0000 (UTC) (envelope-from bdrewery@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id uBDI5EPS054867; Tue, 13 Dec 2016 18:05:14 GMT (envelope-from bdrewery@FreeBSD.org) Received: (from bdrewery@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id uBDI5EDm054866; Tue, 13 Dec 2016 18:05:14 GMT (envelope-from bdrewery@FreeBSD.org) Message-Id: <201612131805.uBDI5EDm054866@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: bdrewery set sender to bdrewery@FreeBSD.org using -f From: Bryan Drewery Date: Tue, 13 Dec 2016 18:05:14 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r310025 - head/libexec/rtld-elf X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 13 Dec 2016 18:05:15 -0000 Author: bdrewery Date: Tue Dec 13 18:05:14 2016 New Revision: 310025 URL: https://svnweb.freebsd.org/changeset/base/310025 Log: Take write lock for rtld_bind before modifying obj_list in dl_iterate_phdr(). This avoids a race with readers such as dladdr(3)/dlinfo(3)/dlsym(3) and the atexit(3) handler. This race was introduced in r294373. Reviewed by: markj, kib, kan MFC after: 2 weeks Sponsored by: Dell EMC Isilon Modified: head/libexec/rtld-elf/rtld.c Modified: head/libexec/rtld-elf/rtld.c ============================================================================== --- head/libexec/rtld-elf/rtld.c Tue Dec 13 16:53:58 2016 (r310024) +++ head/libexec/rtld-elf/rtld.c Tue Dec 13 18:05:14 2016 (r310025) @@ -3549,7 +3549,7 @@ dl_iterate_phdr(__dl_iterate_hdr_callbac error = 0; wlock_acquire(rtld_phdr_lock, &phdr_lockstate); - rlock_acquire(rtld_bind_lock, &bind_lockstate); + wlock_acquire(rtld_bind_lock, &bind_lockstate); for (obj = globallist_curr(TAILQ_FIRST(&obj_list)); obj != NULL;) { TAILQ_INSERT_AFTER(&obj_list, obj, &marker, next); rtld_fill_dl_phdr_info(obj, &phdr_info); @@ -3557,7 +3557,7 @@ dl_iterate_phdr(__dl_iterate_hdr_callbac error = callback(&phdr_info, sizeof phdr_info, param); - rlock_acquire(rtld_bind_lock, &bind_lockstate); + wlock_acquire(rtld_bind_lock, &bind_lockstate); obj = globallist_next(&marker); TAILQ_REMOVE(&obj_list, &marker, next); if (error != 0) {