From d91f0b20e561e326ee91a09a76206257bde8438b Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Sat, 28 Oct 2017 21:31:16 +1030 Subject: [PATCH] PR22361 readelf buffer overflow on fuzzed archive header PR 22361 * readelf.c (process_archive_index_and_symbols): Ensure ar_size field is zero terminated for strtoul. (setup_archive, get_archive_member_name): Likewise. Upstream-Status: Backport Affects: <= 2.29.1 CVE: CVE-2017-15996 Signed-off-by: Armin Kuster --- binutils/ChangeLog | 7 +++++++ binutils/elfcomm.c | 11 +++++++++++ 2 files changed, 18 insertions(+) Index: git/binutils/elfcomm.c =================================================================== --- git.orig/binutils/elfcomm.c +++ git/binutils/elfcomm.c @@ -466,8 +466,12 @@ process_archive_index_and_symbols (struc { size_t got; unsigned long size; + char fmag_save; + fmag_save = arch->arhdr.ar_fmag[0]; + arch->arhdr.ar_fmag[0] = 0; size = strtoul (arch->arhdr.ar_size, NULL, 10); + arch->arhdr.ar_fmag[0] = fmag_save; /* PR 17531: file: 912bd7de. */ if ((signed long) size < 0) { @@ -655,7 +659,10 @@ setup_archive (struct archive_info *arch if (const_strneq (arch->arhdr.ar_name, "// ")) { /* This is the archive string table holding long member names. */ + char fmag_save = arch->arhdr.ar_fmag[0]; + arch->arhdr.ar_fmag[0] = 0; arch->longnames_size = strtoul (arch->arhdr.ar_size, NULL, 10); + arch->arhdr.ar_fmag[0] = fmag_save; /* PR 17531: file: 01068045. */ if (arch->longnames_size < 8) { @@ -758,6 +765,7 @@ get_archive_member_name (struct archive_ char *endp; char *member_file_name; char *member_name; + char fmag_save; if (arch->longnames == NULL || arch->longnames_size == 0) { @@ -766,9 +774,12 @@ get_archive_member_name (struct archive_ } arch->nested_member_origin = 0; + fmag_save = arch->arhdr.ar_fmag[0]; + arch->arhdr.ar_fmag[0] = 0; k = j = strtoul (arch->arhdr.ar_name + 1, &endp, 10); if (arch->is_thin_archive && endp != NULL && * endp == ':') arch->nested_member_origin = strtoul (endp + 1, NULL, 10); + arch->arhdr.ar_fmag[0] = fmag_save; if (j > arch->longnames_size) { Index: git/bfd/ChangeLog =================================================================== --- git.orig/bfd/ChangeLog +++ git/bfd/ChangeLog @@ -1,3 +1,10 @@ +2017-10-28 Alan Modra + + PR 22361 + * readelf.c (process_archive_index_and_symbols): Ensure ar_size + field is zero terminated for strtoul. + (setup_archive, get_archive_member_name): Likewise. + 2017-09-26 Alan Modra PR 22205