From 543691a6cd70b606dd9bed5e77b120c5d9c5c506 Mon Sep 17 00:00:00 2001 From: Andy Whitcroft Date: Sun, 6 May 2007 14:49:33 -0700 Subject: [PATCH] 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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/char/tty_io.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index 7a32df5949..389da364e6 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -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) { -- 2.39.5