Commit 543691a6 authored May 06, 2007 by Andy Whitcroft Committed by Linus Torvalds May 07, 2007

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>

parent b5637e65

drivers/char/tty_io.c

+2 −3

Original line number	Diff line number	Diff line
		@@ -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) {