Bounds check access to Ada task state names
Commit Message
While looking into Ada tasking a little, I noticed that no bounds
checking is done on accesses to the Ada task state names arrays. This
isn't a problem currently, but if the runtime ever added numbers -- or
if there was some kind of runtime corruption -- it could cause a gdb
crash.
This patch adds range checking. It also adds a missing _() call when
printing from the 'task_states' array.
---
gdb/ada-tasks.c | 33 +++++++++++++++++++++++++++++++--
1 file changed, 31 insertions(+), 2 deletions(-)
Comments
>>>>> "Tom" == Tom Tromey via Gdb-patches <gdb-patches@sourceware.org> writes:
Tom> While looking into Ada tasking a little, I noticed that no bounds
Tom> checking is done on accesses to the Ada task state names arrays. This
Tom> isn't a problem currently, but if the runtime ever added numbers -- or
Tom> if there was some kind of runtime corruption -- it could cause a gdb
Tom> crash.
Tom> This patch adds range checking. It also adds a missing _() call when
Tom> printing from the 'task_states' array.
I'm checking this in now.
Tom
@@ -85,6 +85,20 @@ static const char * const task_states[] = {
N_("Selective Wait")
};
+/* Return a string representing the task state. */
+static const char *
+get_state (unsigned value)
+{
+ if (value >= 0
+ && value <= ARRAY_SIZE (task_states)
+ && task_states[value][0] != '\0')
+ return _(task_states[value]);
+
+ static char buffer[100];
+ xsnprintf (buffer, sizeof (buffer), _("Unknown task state: %d"), value);
+ return buffer;
+}
+
/* A longer description corresponding to each possible task state. */
static const char * const long_task_states[] = {
N_("Unactivated"),
@@ -107,6 +121,21 @@ static const char * const long_task_states[] = {
N_("Blocked in selective wait statement")
};
+/* Return a string representing the task state. This uses the long
+ descriptions. */
+static const char *
+get_long_state (unsigned value)
+{
+ if (value >= 0
+ && value <= ARRAY_SIZE (long_task_states)
+ && long_task_states[value][0] != '\0')
+ return _(long_task_states[value]);
+
+ static char buffer[100];
+ xsnprintf (buffer, sizeof (buffer), _("Unknown task state: %d"), value);
+ return buffer;
+}
+
/* The index of certain important fields in the Ada Task Control Block
record and sub-records. */
@@ -1182,7 +1211,7 @@ print_ada_task_info (struct ui_out *uiout,
get_task_number_from_id (task_info->called_task,
inf));
else
- uiout->field_string ("state", task_states[task_info->state]);
+ uiout->field_string ("state", get_state (task_info->state));
/* Finally, print the task name, without quotes around it, as mi like
is not expecting quotes, and in non mi-like no need for quotes
@@ -1276,7 +1305,7 @@ info_task (struct ui_out *uiout, const char *taskno_str, struct inferior *inf)
target_taskno);
}
else
- gdb_printf (_("State: %s"), _(long_task_states[task_info->state]));
+ gdb_printf (_("State: %s"), get_long_state (task_info->state));
if (target_taskno)
{