From FEDORA_PATCHES Mon Sep 17 00:00:00 2001
From: Keith Seitz <keiths@redhat.com>
Date: Tue, 28 Jul 2020 09:26:44 -0400
Subject: gdb-rhbz1842691-corefile-mem-access-11of15.patch
;; Adjust coredump-filter.exp to account for NT_FILE note handling
;; Kevin Buettner, RH BZ 1842961
Author: Kevin Buettner <kevinb@redhat.com>
Date: Fri Jul 3 20:10:22 2020 -0700
Adjust coredump-filter.exp to account for NT_FILE note handling
This commit makes adjustments to coredump-filter.exp to account
for the fact that NT_FILE file-backed mappings are now available
when a core file is loaded. Thus, a test which was expected
to PASS when a memory region was determined to be unavailable
(due to no file-backed mappings being available) will now FAIL
due to those mappings being available from having loaded the
NT_FILE note.
I had originally marked the test as XFAIL, but Mihails Strasuns
suggested a much better approach:
1) First test that it still works if file is accessible in the
filesystem.
2) Temporarily move / rename the file and test that disassembly
doesn't work anymore.
That's what this commit implements.
gdb/testsuite/ChangeLog:
* gdb.base/coredump-filter.exp: Add second
non-Private-Shared-Anon-File test.
(test_disasm): Rename binfile for test which is expected
to fail.
diff --git a/gdb/testsuite/gdb.base/coredump-filter.exp b/gdb/testsuite/gdb.base/coredump-filter.exp
--- a/gdb/testsuite/gdb.base/coredump-filter.exp
+++ b/gdb/testsuite/gdb.base/coredump-filter.exp
@@ -80,15 +80,26 @@ proc do_load_and_test_core { core var working_var working_value dump_excluded }
# disassemble of a function (i.e., the binary's .text section). GDB
# should fail in this case. However, it must succeed if the binary is
# provided along with the corefile. This is what we test here.
+#
+# A further complication is that Linux NT_FILE notes are now read from
+# the corefile. This note allows GDB to find the binary for file
+# backed mappings even though the binary wasn't loaded by GDB in the
+# conventional manner. In order to see the expected failure for this
+# case, we rename the binary in order to perform this test.
proc test_disasm { core address should_fail } {
- global testfile hex
+ global testfile hex binfile
# Restart GDB without loading the binary.
with_test_prefix "no binary" {
gdb_exit
gdb_start
+ set hide_binfile [standard_output_file "${testfile}.hide"]
+ if { $should_fail == 1 } {
+ remote_exec host "mv -f $binfile $hide_binfile"
+ }
+
set core_loaded [gdb_core_cmd "$core" "load core"]
if { $core_loaded == -1 } {
fail "loading $core"
@@ -96,6 +107,7 @@ proc test_disasm { core address should_fail } {
}
if { $should_fail == 1 } {
+ remote_exec host "mv -f $hide_binfile $binfile"
gdb_test "x/i \$pc" "=> $hex:\tCannot access memory at address $hex" \
"disassemble function with corefile and without a binary"
} else {
@@ -225,5 +237,9 @@ foreach item $all_anon_corefiles {
}
with_test_prefix "loading and testing corefile for non-Private-Shared-Anon-File" {
+ test_disasm $non_private_shared_anon_file_core $main_addr 0
+}
+
+with_test_prefix "loading and testing corefile for non-Private-Shared-Anon-File with renamed binary" {
test_disasm $non_private_shared_anon_file_core $main_addr 1
}