Input: serio HIL MLC - don't deref null, don't leak and return proper error
While reviewing various users of kernel memory allocation functions I came
across drivers/input/serio/hil_mlc.c::hil_mlc_register() and noticed that:
- it calls kzalloc() but fails to check for a NULL return before use.
- it makes several allocations and if one fails it doesn't free the
previous ones.
- It doesn't return -ENOMEM in the failed memory allocation case (it just
crashes).
This patch corrects all of the above and also reworks the only caller of
this function that I could find
(drivers/input/serio/hp_sdc_mlc.c::hp_sdc_mlc_out()) so that it now checks
the return value of hil_mlc_register() and properly propagates it on
failure and I also restructured the code to remove some labels and goto's
to make it, IMHO nicer to read.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Tested-by: Helge Deller <deller@gmx.de>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/serio/hp_sdc_mlc.c b/drivers/input/serio/hp_sdc_mlc.c
index 7d2b820..d50f067 100644
--- a/drivers/input/serio/hp_sdc_mlc.c
+++ b/drivers/input/serio/hp_sdc_mlc.c
@@ -305,6 +305,7 @@
static int __init hp_sdc_mlc_init(void)
{
hil_mlc *mlc = &hp_sdc_mlc;
+ int err;
#ifdef __mc68000__
if (!MACH_IS_HP300)
@@ -323,22 +324,21 @@
mlc->out = &hp_sdc_mlc_out;
mlc->priv = &hp_sdc_mlc_priv;
- if (hil_mlc_register(mlc)) {
+ err = hil_mlc_register(mlc);
+ if (err) {
printk(KERN_WARNING PREFIX "Failed to register MLC structure with hil_mlc\n");
- goto err0;
+ return err;
}
if (hp_sdc_request_hil_irq(&hp_sdc_mlc_isr)) {
printk(KERN_WARNING PREFIX "Request for raw HIL ISR hook denied\n");
- goto err1;
+ if (hil_mlc_unregister(mlc))
+ printk(KERN_ERR PREFIX "Failed to unregister MLC structure with hil_mlc.\n"
+ "This is bad. Could cause an oops.\n");
+ return -EBUSY;
}
+
return 0;
- err1:
- if (hil_mlc_unregister(mlc))
- printk(KERN_ERR PREFIX "Failed to unregister MLC structure with hil_mlc.\n"
- "This is bad. Could cause an oops.\n");
- err0:
- return -EBUSY;
}
static void __exit hp_sdc_mlc_exit(void)