From 09dd135df9ebc7a4b640537e23e26a03a288a789 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Wed, 9 Oct 2019 00:07:29 +1030 Subject: [PATCH] PR25078, stack overflow in function find_abstract_instance Selectively backporting fix for bfd/dwarf2.c, but not the ChangeLog file. There are newer versions of binutils, but none of them contain the commit fixing CVE-2019-17450, so backport it to master and zeus. Upstream-Status: Backport [https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=063c511bd79] CVE: CVE-2019-17450 Signed-off-by: Trevor Gamblin PR 25078 * dwarf2.c (find_abstract_instance): Delete orig_info_ptr, add recur_count. Error on recur_count reaching 100 rather than info_ptr matching orig_info_ptr. Adjust calls. --- bfd/dwarf2.c | 35 +++++++++++++++++------------------ 1 file changed, 17 insertions(+), 18 deletions(-) diff --git a/bfd/dwarf2.c b/bfd/dwarf2.c index 0b4e485582..20ec9e2e56 100644 --- a/bfd/dwarf2.c +++ b/bfd/dwarf2.c @@ -2803,13 +2803,13 @@ lookup_symbol_in_variable_table (struct comp_unit *unit, } static bfd_boolean -find_abstract_instance (struct comp_unit * unit, - bfd_byte * orig_info_ptr, - struct attribute * attr_ptr, - const char ** pname, - bfd_boolean * is_linkage, - char ** filename_ptr, - int * linenumber_ptr) +find_abstract_instance (struct comp_unit *unit, + struct attribute *attr_ptr, + unsigned int recur_count, + const char **pname, + bfd_boolean *is_linkage, + char **filename_ptr, + int *linenumber_ptr) { bfd *abfd = unit->abfd; bfd_byte *info_ptr; @@ -2820,6 +2820,14 @@ find_abstract_instance (struct comp_unit * unit, struct attribute attr; const char *name = NULL; + if (recur_count == 100) + { + _bfd_error_handler + (_("DWARF error: abstract instance recursion detected")); + bfd_set_error (bfd_error_bad_value); + return FALSE; + } + /* DW_FORM_ref_addr can reference an entry in a different CU. It is an offset from the .debug_info section, not the current CU. */ if (attr_ptr->form == DW_FORM_ref_addr) @@ -2939,15 +2947,6 @@ find_abstract_instance (struct comp_unit * unit, info_ptr, info_ptr_end); if (info_ptr == NULL) break; - /* It doesn't ever make sense for DW_AT_specification to - refer to the same DIE. Stop simple recursion. */ - if (info_ptr == orig_info_ptr) - { - _bfd_error_handler - (_("DWARF error: abstract instance recursion detected")); - bfd_set_error (bfd_error_bad_value); - return FALSE; - } switch (attr.name) { case DW_AT_name: @@ -2961,7 +2960,7 @@ find_abstract_instance (struct comp_unit * unit, } break; case DW_AT_specification: - if (!find_abstract_instance (unit, info_ptr, &attr, + if (!find_abstract_instance (unit, &attr, recur_count + 1, &name, is_linkage, filename_ptr, linenumber_ptr)) return FALSE; @@ -3175,7 +3174,7 @@ scan_unit_for_symbols (struct comp_unit *unit) case DW_AT_abstract_origin: case DW_AT_specification: - if (!find_abstract_instance (unit, info_ptr, &attr, + if (!find_abstract_instance (unit, &attr, 0, &func->name, &func->is_linkage, &func->file, -- 2.23.0