2008-01-13 17:36:20

by Stefano Brivio

Subject: [PATCH] b43: fix use-after-free rfkill bug

Fix rfkill code which caused a use-after-free bug.

Signed-off-by: Stefano Brivio <[email protected]>
---
Index: wireless-2.6/drivers/net/wireless/b43/rfkill.c
===================================================================
--- wireless-2.6.orig/drivers/net/wireless/b43/rfkill.c
+++ wireless-2.6/drivers/net/wireless/b43/rfkill.c
@@ -138,8 +138,11 @@ void b43_rfkill_init(struct b43_wldev *d
rfk->rfkill->user_claim_unsupported = 1;

rfk->poll_dev = input_allocate_polled_device();
- if (!rfk->poll_dev)
- goto err_free_rfk;
+ if (!rfk->poll_dev) {
+ rfkill_free(rfk->rfkill);
+ goto err_freed_rfk;
+ }
+
rfk->poll_dev->private = dev;
rfk->poll_dev->poll = b43_rfkill_poll;
rfk->poll_dev->poll_interval = 1000; /* msecs */
@@ -175,8 +178,7 @@ err_unreg_rfk:
err_free_polldev:
input_free_polled_device(rfk->poll_dev);
rfk->poll_dev = NULL;
-err_free_rfk:
- rfkill_free(rfk->rfkill);
+err_freed_rfk:
rfk->rfkill = NULL;
out_error:
rfk->registered = 0;
@@ -195,6 +197,5 @@ void b43_rfkill_exit(struct b43_wldev *d
rfkill_unregister(rfk->rfkill);
input_free_polled_device(rfk->poll_dev);
rfk->poll_dev = NULL;
- rfkill_free(rfk->rfkill);
rfk->rfkill = NULL;
}


--
Ciao
Stefano

2008-01-13 17:42:37

by Michael Büsch

Subject: Re: [PATCH] b43: fix use-after-free rfkill bug

On Sunday 13 January 2008 18:30:14 Stefano Brivio wrote:
> Fix rfkill code which caused a use-after-free bug.
>
> Signed-off-by: Stefano Brivio <[email protected]>
> ---
> Index: wireless-2.6/drivers/net/wireless/b43/rfkill.c
> ===================================================================
> --- wireless-2.6.orig/drivers/net/wireless/b43/rfkill.c
> +++ wireless-2.6/drivers/net/wireless/b43/rfkill.c
> @@ -138,8 +138,11 @@ void b43_rfkill_init(struct b43_wldev *d
> rfk->rfkill->user_claim_unsupported = 1;
>
> rfk->poll_dev = input_allocate_polled_device();
> - if (!rfk->poll_dev)
> - goto err_free_rfk;
> + if (!rfk->poll_dev) {
> + rfkill_free(rfk->rfkill);
> + goto err_freed_rfk;
> + }
> +
> rfk->poll_dev->private = dev;
> rfk->poll_dev->poll = b43_rfkill_poll;
> rfk->poll_dev->poll_interval = 1000; /* msecs */
> @@ -175,8 +178,7 @@ err_unreg_rfk:
> err_free_polldev:
> input_free_polled_device(rfk->poll_dev);
> rfk->poll_dev = NULL;
> -err_free_rfk:
> - rfkill_free(rfk->rfkill);
> +err_freed_rfk:
> rfk->rfkill = NULL;
> out_error:
> rfk->registered = 0;
> @@ -195,6 +197,5 @@ void b43_rfkill_exit(struct b43_wldev *d
> rfkill_unregister(rfk->rfkill);
> input_free_polled_device(rfk->poll_dev);
> rfk->poll_dev = NULL;
> - rfkill_free(rfk->rfkill);
> rfk->rfkill = NULL;
> }

Acked-by: Michael Buesch <[email protected]>

--
Greetings Michael.