[PATCH] hvc_console: Add some sanity checks
Check if a vterm was registered before accepting it as a console.
Check that a slot hasn't been probed with a tty in hvc_instantiate().
Check that a slot hasn't been free'ed when handing out console device.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c
index de849f5..7bc65a7 100644
--- a/drivers/char/hvc_console.c
+++ b/drivers/char/hvc_console.c
@@ -192,12 +192,21 @@
static struct tty_driver *hvc_console_device(struct console *c, int *index)
{
+ if (vtermnos[c->index] == -1)
+ return NULL;
+
*index = c->index;
return hvc_driver;
}
static int __init hvc_console_setup(struct console *co, char *options)
{
+ if (co->index < 0 || co->index >= MAX_NR_HVC_CONSOLES)
+ return -ENODEV;
+
+ if (vtermnos[co->index] == -1)
+ return -ENODEV;
+
return 0;
}
@@ -227,12 +236,21 @@
*/
int hvc_instantiate(uint32_t vtermno, int index)
{
+ struct hvc_struct *hp;
+
if (index < 0 || index >= MAX_NR_HVC_CONSOLES)
return -1;
if (vtermnos[index] != -1)
return -1;
+ /* make sure no no tty has been registerd in this index */
+ hp = hvc_get_by_index(index);
+ if (hp) {
+ kobject_put(&hp->kobj);
+ return -1;
+ }
+
vtermnos[index] = vtermno;
/* reserve all indices upto and including this index */