Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759911Ab2HIWWY (ORCPT ); Thu, 9 Aug 2012 18:22:24 -0400 Received: from e9.ny.us.ibm.com ([32.97.182.139]:47306 "EHLO e9.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759859Ab2HIWWJ (ORCPT ); Thu, 9 Aug 2012 18:22:09 -0400 From: Cody P Schafer To: Arnaldo Carvalho de Melo Cc: LKML , Ingo Molnar , Paul Mackerras , Peter Zijlstra , Sukadev Bhattiprolu , Matt Hellsley , David Hansen Subject: [PATCH 09/16] perf symbol: avoid segfault in elf_strptr Date: Thu, 9 Aug 2012 15:18:34 -0700 Message-Id: <1344550721-21024-10-git-send-email-cody@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.11.3 In-Reply-To: <1344550721-21024-1-git-send-email-cody@linux.vnet.ibm.com> References: <1344550721-21024-1-git-send-email-cody@linux.vnet.ibm.com> X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12080922-7182-0000-0000-0000023E0488 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1198 Lines: 37 If we call elf_section_by_name() with a truncated elf image (ie: the file header indicates that the section headers are placed past the end of the file), elf_strptr() causes a segfault within libelf. Avoid this by checking that we can access the section string table properly. Should really be fixed in libelf/elfutils. Signed-off-by: Cody P Schafer --- tools/perf/util/symbol.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 9e31cbb..6afc92d 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -973,6 +973,10 @@ static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep, Elf_Scn *sec = NULL; size_t cnt = 1; + /* Elf is corrupted/truncated, avoid calling elf_strptr. */ + if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) + return NULL; + while ((sec = elf_nextscn(elf, sec)) != NULL) { char *str; -- 1.7.11.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/