From owner-svn-src-all@freebsd.org Sun Feb 5 02:44:09 2017 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 CF8F0CD1884; Sun, 5 Feb 2017 02:44:09 +0000 (UTC) (envelope-from markj@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 81F44E3A; Sun, 5 Feb 2017 02:44:09 +0000 (UTC) (envelope-from markj@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id v152i8L9018235; Sun, 5 Feb 2017 02:44:08 GMT (envelope-from markj@FreeBSD.org) Received: (from markj@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id v152i8QW018234; Sun, 5 Feb 2017 02:44:08 GMT (envelope-from markj@FreeBSD.org) Message-Id: <201702050244.v152i8QW018234@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: markj set sender to markj@FreeBSD.org using -f From: Mark Johnston Date: Sun, 5 Feb 2017 02:44:08 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r313263 - head/cddl/contrib/opensolaris/lib/libdtrace/common 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: Sun, 05 Feb 2017 02:44:09 -0000 Author: markj Date: Sun Feb 5 02:44:08 2017 New Revision: 313263 URL: https://svnweb.freebsd.org/changeset/base/313263 Log: Fix a double free of libelf data buffers in the USDT link code. libdtrace needs to append to the input object files' string and symbol tables. Currently it does so by allocating a larger buffer, copying the existing sections into them, and swapping pointers in the libelf data descriptors. However, it also frees those buffers when its processing is complete, which leads to a double free since the elftoolchain libelf owns them and also frees them in elf_end(3). Instead, free the buffers originally allocated by libelf. MFC after: 2 weeks Modified: head/cddl/contrib/opensolaris/lib/libdtrace/common/dt_link.c Modified: head/cddl/contrib/opensolaris/lib/libdtrace/common/dt_link.c ============================================================================== --- head/cddl/contrib/opensolaris/lib/libdtrace/common/dt_link.c Sun Feb 5 02:39:12 2017 (r313262) +++ head/cddl/contrib/opensolaris/lib/libdtrace/common/dt_link.c Sun Feb 5 02:44:08 2017 (r313263) @@ -1205,6 +1205,7 @@ process_obj(dtrace_hdl_t *dtp, const cha key_t objkey; dt_link_pair_t *pair, *bufs = NULL; dt_strtab_t *strtab; + void *tmp; if ((fd = open64(obj, O_RDWR)) == -1) { return (dt_link_error(dtp, elf, fd, bufs, @@ -1463,7 +1464,9 @@ process_obj(dtrace_hdl_t *dtp, const cha bufs = pair; bcopy(data_str->d_buf, pair->dlp_str, data_str->d_size); + tmp = data_str->d_buf; data_str->d_buf = pair->dlp_str; + pair->dlp_str = tmp; data_str->d_size += len; (void) elf_flagdata(data_str, ELF_C_SET, ELF_F_DIRTY); @@ -1471,7 +1474,9 @@ process_obj(dtrace_hdl_t *dtp, const cha (void) gelf_update_shdr(scn_str, &shdr_str); bcopy(data_sym->d_buf, pair->dlp_sym, data_sym->d_size); + tmp = data_sym->d_buf; data_sym->d_buf = pair->dlp_sym; + pair->dlp_sym = tmp; data_sym->d_size += nsym * symsize; (void) elf_flagdata(data_sym, ELF_C_SET, ELF_F_DIRTY); @@ -1657,9 +1662,6 @@ process_obj(dtrace_hdl_t *dtp, const cha (void) elf_end(elf); (void) close(fd); -#ifndef illumos - if (nsym > 0) -#endif while ((pair = bufs) != NULL) { bufs = pair->dlp_next; dt_free(dtp, pair->dlp_str);