Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753675Ab2HMSiV (ORCPT ); Mon, 13 Aug 2012 14:38:21 -0400 Received: from merlin.infradead.org ([205.233.59.134]:49397 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752607Ab2HMShj (ORCPT ); Mon, 13 Aug 2012 14:37:39 -0400 From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Cody P Schafer , David Hansen , Ingo Molnar , Matt Hellsley , Namhyung Kim , Paul Mackerras , Peter Zijlstra , Sukadev Bhattiprolu , Arnaldo Carvalho de Melo Subject: [PATCH 30/38] perf symbols: Avoid segfault in elf_strptr Date: Mon, 13 Aug 2012 15:37:11 -0300 Message-Id: <1344883039-13495-31-git-send-email-acme@infradead.org> X-Mailer: git-send-email 1.7.9.2.358.g22243 In-Reply-To: <1344883039-13495-1-git-send-email-acme@infradead.org> References: <1344883039-13495-1-git-send-email-acme@infradead.org> Content-Type: text/plain; charset="UTF-8" X-SRS-Rewrite: SMTP reverse-path rewritten from by canuck.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1723 Lines: 48 From: Cody P Schafer 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 Cc: David Hansen Cc: Ingo Molnar Cc: Matt Hellsley Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Sukadev Bhattiprolu Link: http://lkml.kernel.org/r/1344637382-22789-10-git-send-email-cody@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/symbol-elf.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index a2e994e..a9a194d 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -129,6 +129,10 @@ 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; -- 1.7.1 -- 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/