From: Tom de Vries <tdevries@suse.de>
To: gdb-patches@sourceware.org
Cc: Kevin Buettner <kevinb@redhat.com>
Subject: [PATCH] [gdb/symtab] Fix overly large gdb-index file check for 32-bit
Date: Fri, 15 Sep 2023 11:08:37 +0200 [thread overview]
Message-ID: <20230915090837.16945-1-tdevries@suse.de> (raw)
Add a unit test which checks that write_gdb_index_1 will throw
an error when the size of the file would exceed the maximum value
capable of being represented by 'offset_type'.
The unit test fails on 32-bit systems due to wrapping overflow. Fix this by
changing the type of total_len in write_gdbindex_1 from size_t to uint64_t.
Tested on x86_64-linux.
Co-Authored-By: Kevin Buettner <kevinb@redhat.com>
---
gdb/dwarf2/index-write.c | 84 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 82 insertions(+), 2 deletions(-)
diff --git a/gdb/dwarf2/index-write.c b/gdb/dwarf2/index-write.c
index 3827a810130..1b5d4c10b0c 100644
--- a/gdb/dwarf2/index-write.c
+++ b/gdb/dwarf2/index-write.c
@@ -137,7 +137,7 @@ class data_buf
}
/* Return the size of the buffer. */
- size_t size () const
+ virtual size_t size () const
{
return m_vec.size ();
}
@@ -1083,7 +1083,7 @@ write_gdbindex_1 (FILE *out_file,
{
data_buf contents;
const offset_type size_of_header = 6 * sizeof (offset_type);
- size_t total_len = size_of_header;
+ uint64_t total_len = size_of_header;
/* The version number. */
contents.append_offset (8);
@@ -1117,6 +1117,9 @@ write_gdbindex_1 (FILE *out_file,
if (total_len > max_size)
error (_("gdb-index maximum file size of %zu exceeded"), max_size);
+ if (out_file == nullptr)
+ return;
+
contents.file_write (out_file);
cu_list.file_write (out_file);
types_cu_list.file_write (out_file);
@@ -1537,10 +1540,87 @@ save_gdb_index_command (const char *arg, int from_tty)
}
}
+#if GDB_SELF_TEST
+#include "gdbsupport/selftest.h"
+
+namespace selftests {
+
+class pretend_data_buf : public data_buf
+{
+public:
+ /* Set the pretend size. */
+ void set_pretend_size (size_t s) {
+ m_pretend_size = s;
+ }
+
+ /* Override size method of data_buf, returning the pretend size instead. */
+ size_t size () const override {
+ return m_pretend_size;
+ }
+
+private:
+ size_t m_pretend_size = 0;
+};
+
+static void
+gdb_index ()
+{
+ pretend_data_buf cu_list;
+ pretend_data_buf types_cu_list;
+ pretend_data_buf addr_vec;
+ pretend_data_buf symtab_vec;
+ pretend_data_buf constant_pool;
+
+ const size_t size_of_header = 6 * sizeof (offset_type);
+
+ /* Test that an overly large index will throw an error. */
+ symtab_vec.set_pretend_size (~(offset_type)0 - size_of_header);
+ constant_pool.set_pretend_size (1);
+
+ bool saw_exception = false;
+ try
+ {
+ write_gdbindex_1 (nullptr, cu_list, types_cu_list, addr_vec,
+ symtab_vec, constant_pool);
+ }
+ catch (const gdb_exception_error &e)
+ {
+ SELF_CHECK (e.reason == RETURN_ERROR);
+ SELF_CHECK (e.error == GENERIC_ERROR);
+ SELF_CHECK (e.message->find (_("gdb-index maximum file size of"))
+ != std::string::npos);
+ SELF_CHECK (e.message->find (_("exceeded")) != std::string::npos);
+ saw_exception = true;
+ }
+ SELF_CHECK (saw_exception);
+
+ /* Test that the largest possible index will not throw an error. */
+ constant_pool.set_pretend_size (0);
+
+ saw_exception = false;
+ try
+ {
+ write_gdbindex_1 (nullptr, cu_list, types_cu_list, addr_vec,
+ symtab_vec, constant_pool);
+ }
+ catch (const gdb_exception_error &e)
+ {
+ saw_exception = true;
+ }
+ SELF_CHECK (!saw_exception);
+}
+
+} /* selftests namespace. */
+#endif
+
void _initialize_dwarf_index_write ();
void
_initialize_dwarf_index_write ()
{
+#if GDB_SELF_TEST
+ selftests::register_test ("gdb_index", selftests::gdb_index);
+#endif
+
cmd_list_element *c = add_cmd ("gdb-index", class_files,
save_gdb_index_command, _("\
Save a gdb-index file.\n\
base-commit: 95fc47d5c6b363b9b195baf1850b0ba95438ce69
--
2.35.3
next reply other threads:[~2023-09-15 9:08 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-15 9:08 Tom de Vries [this message]
2023-09-15 21:38 ` Kevin Buettner
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