Commit 4daa9ff8 authored by Luiz Sampaio's avatar Luiz Sampaio Committed by Miguel Ojeda
Browse files

auxdisplay: charlcd: checking for pointer reference before dereferencing 



Check if the pointer lcd->ops->init_display exists before dereferencing it.
If a driver called charlcd_init() without defining the ops, this would
return segmentation fault, as happened to me when implementing a charlcd
driver.  Checking the pointer before dereferencing protects from
segmentation fault.

Signed-off-by: default avatarLuiz Sampaio <sampaio.ime@gmail.com>
Signed-off-by: default avatarMiguel Ojeda <ojeda@kernel.org>
parent 94047df1

drivers/auxdisplay/charlcd.c

+3 −0
Original line number Diff line number Diff line
@@ -578,6 +578,9 @@ static int charlcd_init(struct charlcd *lcd) 
	 * Since charlcd_init_display() needs to write data, we have to

	 * enable mark the LCD initialized just before.

	 */

	if (WARN_ON(!lcd->ops->init_display))

		return -EINVAL;



	ret = lcd->ops->init_display(lcd);

	if (ret)

		return ret;