From d11ae95ea3403559f052903ab053f43ad7821e37 Mon Sep 17 00:00:00 2001 From: Nick Clifton Date: Thu, 1 Mar 2018 16:14:08 +0000 Subject: [PATCH] Prevent illegal memory accesses triggerd by intger overflow when parsing corrupt DWARF information on a 32-bit host. PR 22905 * dwarf.c (display_debug_ranges): Check that the offset loaded from the range_entry structure is valid. Upstream-Status: Backport Affects: Binutils <= 2.30 CVE: CVE-2018-7643 Signed-off-by: Armin Kuster --- binutils/ChangeLog | 6 ++++++ binutils/dwarf.c | 15 +++++++++++++++ 2 files changed, 21 insertions(+) Index: git/binutils/dwarf.c =================================================================== --- git.orig/binutils/dwarf.c +++ git/binutils/dwarf.c @@ -387,6 +387,9 @@ read_uleb128 (unsigned char * data, } \ while (0) +/* Read AMOUNT bytes from PTR and store them in VAL as an unsigned value. + Checks to make sure that the read will not reach or pass END + and that VAL is big enough to hold AMOUNT bytes. */ #define SAFE_BYTE_GET(VAL, PTR, AMOUNT, END) \ do \ { \ @@ -415,6 +418,7 @@ read_uleb128 (unsigned char * data, } \ while (0) +/* Like SAFE_BYTE_GET, but also increments PTR by AMOUNT. */ #define SAFE_BYTE_GET_AND_INC(VAL, PTR, AMOUNT, END) \ do \ { \ @@ -423,6 +427,7 @@ read_uleb128 (unsigned char * data, } \ while (0) +/* Like SAFE_BYTE_GET, but reads a signed value. */ #define SAFE_SIGNED_BYTE_GET(VAL, PTR, AMOUNT, END) \ do \ { \ @@ -441,6 +446,7 @@ read_uleb128 (unsigned char * data, } \ while (0) +/* Like SAFE_SIGNED_BYTE_GET, but also increments PTR by AMOUNT. */ #define SAFE_SIGNED_BYTE_GET_AND_INC(VAL, PTR, AMOUNT, END) \ do \ { \ @@ -6543,6 +6549,7 @@ display_debug_ranges_list (unsigned char break; SAFE_SIGNED_BYTE_GET_AND_INC (end, start, pointer_size, finish); + printf (" %8.8lx ", offset); if (begin == 0 && end == 0) @@ -6810,6 +6817,13 @@ display_debug_ranges (struct dwarf_secti continue; } + if (next < section_begin || next >= finish) + { + warn (_("Corrupt offset (%#8.8lx) in range entry %u\n"), + (unsigned long) offset, i); + continue; + } + if (dwarf_check != 0 && i > 0) { if (start < next) @@ -6825,6 +6839,7 @@ display_debug_ranges (struct dwarf_secti (unsigned long) (next - section_begin), section->name); } } + start = next; last_start = next; Index: git/bfd/ChangeLog =================================================================== --- git.orig/bfd/ChangeLog +++ git/bfd/ChangeLog @@ -1,3 +1,9 @@ +2018-03-01 Nick Clifton + + PR 22905 + * dwarf.c (display_debug_ranges): Check that the offset loaded + from the range_entry structure is valid. + 2018-05-08 Nick Clifton PR 22809