From 492746546fe380da768c8496213e26aa91b9b3aa Mon Sep 17 00:00:00 2001 From: Cody P Schafer Date: Fri, 10 Aug 2012 15:22:55 -0700 Subject: [PATCH] perf symbols: Avoid segfault in elf_strptr 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 file changed, 4 insertions(+) diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index a2e994e2605f..a9a194d49c1b 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;