tty_register_driver: only allocate tty instances when defined

If device->num is zero we attempt to kmalloc() zero bytes.  When SLUB is
enabled this returns a null pointer and take that as an allocation failure
and fail the device register.  Check for no devices and avoid the
allocation.

[akpm: opportunistic kzalloc() conversion]
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Andy Whitcroft 2007-05-06 14:49:33 -07:00 committed by Linus Torvalds
parent b5637e65ee
commit 543691a6cd

View File

@ -3720,11 +3720,10 @@ int tty_register_driver(struct tty_driver *driver)
if (driver->flags & TTY_DRIVER_INSTALLED)
return 0;
if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM)) {
p = kmalloc(driver->num * 3 * sizeof(void *), GFP_KERNEL);
if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM) && driver->num) {
p = kzalloc(driver->num * 3 * sizeof(void *), GFP_KERNEL);
if (!p)
return -ENOMEM;
memset(p, 0, driver->num * 3 * sizeof(void *));
}
if (!driver->major) {