From 47fea877452b84b94ac6ffb26f194f12845526fa Mon Sep 17 00:00:00 2001 From: Ruslan Kabatsayev Date: Sat, 30 Dec 2017 22:14:41 +0300 Subject: [PATCH] Avoid indexing std::vector past the end The code here wants to find address of an element, and often this element is one past the end of std::vector. Dereferencing that element leads to undefined behavior, so it's better to simply use pointer arithmetic instead of taking address of invalid dereference. gdb/ChangeLog: * psymtab.c (recursively_search_psymtabs): Use pointer arithmetic instead of dereferencing std::vector past the end. --- gdb/ChangeLog | 5 +++++ gdb/psymtab.c | 8 ++++---- 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index edb3cd452f..aaadf142a4 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +2017-12-31 Ruslan Kabatsayev + + * psymtab.c (recursively_search_psymtabs): Use pointer arithmetic + instead of dereferencing std::vector past the end. + 2017-12-30 Simon Marchi * common/diagnostics.h diff --git a/gdb/psymtab.c b/gdb/psymtab.c index c87ef25d61..1271e18296 100644 --- a/gdb/psymtab.c +++ b/gdb/psymtab.c @@ -1337,21 +1337,21 @@ recursively_search_psymtabs } partial_symbol **gbound - = &objfile->global_psymbols[ps->globals_offset + ps->n_global_syms]; + = objfile->global_psymbols.data () + ps->globals_offset + ps->n_global_syms; partial_symbol **sbound - = &objfile->static_psymbols[ps->statics_offset + ps->n_static_syms]; + = objfile->static_psymbols.data () + ps->statics_offset + ps->n_static_syms; partial_symbol **bound = gbound; /* Go through all of the symbols stored in a partial symtab in one loop. */ - partial_symbol **psym = &objfile->global_psymbols[ps->globals_offset]; + partial_symbol **psym = objfile->global_psymbols.data () + ps->globals_offset; while (keep_going) { if (psym >= bound) { if (bound == gbound && ps->n_static_syms != 0) { - psym = &objfile->static_psymbols[ps->statics_offset]; + psym = objfile->static_psymbols.data () + ps->statics_offset; bound = sbound; } else