From 2123df0ebfc7ade46784ef412226490d59f8ce05 Mon Sep 17 00:00:00 2001 From: Yao Qi Date: Mon, 27 Feb 2017 17:27:17 +0000 Subject: [PATCH] Fix array out of bound access ASAN reports the following error, (gdb) PASS: gdb.fortran/vla-ptr-info.exp: continue to breakpoint: pvla-associated print &pvla^M =================================================================^M ^[[1m^[[31m==14331==ERROR: AddressSanitizer: global-buffer-overflow on address 0x000000ea569f at pc 0x0000008eb546 bp 0x7ffde0c1dc70 sp 0x7ffde0c1dc60^M ^[[1m^[[0m^[[1m^[[34mREAD of size 1 at 0x000000ea569f thread T0^[[1m^[[0m^M #0 0x8eb545 in f_print_type(type*, char const*, ui_file*, int, int, type_print_options const*) ../../binutils-gdb/gdb/f-typeprint.c:89^M #1 0xb611e2 in type_print(type*, char const*, ui_file*, int) ../../binutils-gdb/gdb/typeprint.c:365^M #2 0x7b3471 in c_value_print(value*, ui_file*, value_print_options const*) ../../binutils-gdb/gdb/c-valprint.c:650^M #3 0xb99517 in value_print(value*, ui_file*, value_print_options const*) ../../binutils-gdb/gdb/valprint.c:1233^M #4 0xa42be8 in print_formatted ../../binutils-gdb/gdb/printcmd.c:321^M #5 0xa46ac9 in print_value(value*, format_data const*) ../../binutils-gdb/gdb/printcmd.c:1233^M #6 0xa46d82 in print_command_1 ../../binutils-gdb/gdb/printcmd.c:1261^M #7 0xa46e3e in print_command ../../binutils-gdb/gdb/printcmd.c:1267 on this line of code demangled_args = varstring[strlen (varstring) - 1] == ')'; because varstring is an empty string and strlen () is 0, so "strlen () - 1" is definitely out of the bound of "varstring", (gdb) bt 10 at /home/yao/SourceCode/gnu/gdb/git/gdb/f-typeprint.c:56 at /home/yao/SourceCode/gnu/gdb/git/gdb/typeprint.c:365 at /home/yao/SourceCode/gnu/gdb/git/gdb/c-valprint.c:650 at /home/yao/SourceCode/gnu/gdb/git/gdb/valprint.c:1236 This patch adds a pre-check that varstring is empty or not. gdb: 2017-02-27 Yao Qi * f-typeprint.c (f_print_type): Check "varstring" is empty first. --- gdb/ChangeLog | 4 ++++ gdb/f-typeprint.c | 6 ++++-- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index c9fdd66f27..a7be8266ea 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,7 @@ +2017-02-27 Yao Qi + + * f-typeprint.c (f_print_type): Check "varstring" is empty first. + 2017-02-26 Alan Hayward * regcache.c (regcache_raw_update): New function. diff --git a/gdb/f-typeprint.c b/gdb/f-typeprint.c index da6ef4f92e..7dbe093a7f 100644 --- a/gdb/f-typeprint.c +++ b/gdb/f-typeprint.c @@ -52,7 +52,6 @@ f_print_type (struct type *type, const char *varstring, struct ui_file *stream, int show, int level, const struct type_print_options *flags) { enum type_code code; - int demangled_args; if (type_not_associated (type)) { @@ -81,12 +80,15 @@ f_print_type (struct type *type, const char *varstring, struct ui_file *stream, if (varstring != NULL) { + int demangled_args; + fputs_filtered (varstring, stream); /* For demangled function names, we have the arglist as part of the name, so don't print an additional pair of ()'s. */ - demangled_args = varstring[strlen (varstring) - 1] == ')'; + demangled_args = (*varstring != '\0' + && varstring[strlen (varstring) - 1] == ')'); f_type_print_varspec_suffix (type, stream, show, 0, demangled_args, 0); } }