From 30bcc01478433a1cb05b36dc5c4beef7d2c89b5b Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Fri, 21 Jun 2019 11:51:38 +0930 Subject: [PATCH] PR24689, string table corruption The testcase in the PR had a e_shstrndx section of type SHT_GROUP. hdr->contents were initialized by setup_group rather than being read from the file, thus last byte was not zero and string dereference ran off the end of the buffer. PR 24689 * elfcode.h (elf_object_p): Check type of e_shstrndx section. Upstream-Status: Backport CVE: CVE-2019-12972 Signed-off-by: Anuj Mittal --- bfd/ChangeLog | 5 +++++ bfd/elfcode.h | 3 ++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 91f09e6346..e66fb40a2c 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,8 @@ +2019-06-21 Alan Modra + + PR 24689 + * elfcode.h (elf_object_p): Check type of e_shstrndx section. + 2019-02-20 Alan Modra PR 24236 diff --git a/bfd/elfcode.h b/bfd/elfcode.h index ec5ea766de..a35a629087 100644 --- a/bfd/elfcode.h +++ b/bfd/elfcode.h @@ -755,7 +755,8 @@ elf_object_p (bfd *abfd) /* A further sanity check. */ if (i_ehdrp->e_shnum != 0) { - if (i_ehdrp->e_shstrndx >= elf_numsections (abfd)) + if (i_ehdrp->e_shstrndx >= elf_numsections (abfd) + || i_shdrp[i_ehdrp->e_shstrndx].sh_type != SHT_STRTAB) { /* PR 2257: We used to just goto got_wrong_format_error here -- 2.20.1