From patchwork Mon Jan 15 15:08:42 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Weimer X-Patchwork-Id: 25399 Received: (qmail 105678 invoked by alias); 15 Jan 2018 15:08:47 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 105478 invoked by uid 89); 15 Jan 2018 15:08:46 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-26.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, SPF_HELO_PASS, T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 spammy=1007 X-HELO: mx1.redhat.com Date: Mon, 15 Jan 2018 16:08:42 +0100 To: libc-alpha@sourceware.org Subject: [PATCH] nptl: Open libgcc.so with RTLD_NOW during pthread_cancel [BZ #22636] User-Agent: Heirloom mailx 12.5 7/5/10 MIME-Version: 1.0 Message-Id: <20180115150842.B32134034FFB3@oldenburg.str.redhat.com> From: fweimer@redhat.com (Florian Weimer) Disabling lazy binding reduces stack usage during unwinding. Note that RTLD_NOW only makes a difference if libgcc.so has not already been loaded, so this is only a partial fix. Reviewed-by: Adhemerval Zanella (cherry picked from commit f993b8754080ac7572b692870e926d8b493db16c) 2018-01-10 Florian Weimer [BZ #22636] * sysdeps/nptl/unwind-forcedunwind.c (pthread_cancel_init): Open libgcc.so with RTLD_NOW, to avoid lazy binding during unwind. diff --git a/NEWS b/NEWS index 3a719e81e3..afa170f86e 100644 --- a/NEWS +++ b/NEWS @@ -100,6 +100,7 @@ The following bugs are resolved with this release: [22322] libc: [mips64] wrong bits/long-double.h installed [22325] glibc: Memory leak in glob with GLOB_TILDE (CVE-2017-15671) [22375] malloc returns pointer from tcache instead of NULL (CVE-2017-17426) + [22636] PTHREAD_STACK_MIN is too small on x86-64 [22627] $ORIGIN in $LD_LIBRARY_PATH is substituted twice [22637] nptl: Fix stack guard size accounting [22679] getcwd(3) can succeed without returning an absolute path diff --git a/sysdeps/nptl/unwind-forcedunwind.c b/sysdeps/nptl/unwind-forcedunwind.c index 33a1975f5e..ace58b2468 100644 --- a/sysdeps/nptl/unwind-forcedunwind.c +++ b/sysdeps/nptl/unwind-forcedunwind.c @@ -49,7 +49,7 @@ pthread_cancel_init (void) return; } - handle = __libc_dlopen (LIBGCC_S_SO); + handle = __libc_dlopen_mode (LIBGCC_S_SO, RTLD_NOW | __RTLD_DLOPEN); if (handle == NULL || (resume = __libc_dlsym (handle, "_Unwind_Resume")) == NULL