Re: [PATCH] rtlwifi: Fix null-pointer dereferences in error handling code of rtl_pci_probe()

From: Kalle Valo
Date: Tue May 28 2019 - 07:59:17 EST


Jia-Ju Bai <baijiaju1990@xxxxxxxxx> wrote:

> *BUG 1:
> In rtl_pci_probe(), when rtlpriv->cfg->ops->init_sw_vars() fails,
> rtl_deinit_core() in the error handling code is executed.
> rtl_deinit_core() calls rtl_free_entries_from_scan_list(), which uses
> rtlpriv->scan_list.list in list_for_each_entry_safe(), but it has been
> initialized. Thus a null-pointer dereference occurs.
> The reason is that rtlpriv->scan_list.list is initialized by
> INIT_LIST_HEAD() in rtl_init_core(), which has not been called.
>
> To fix this bug, rtl_deinit_core() should not be called when
> rtlpriv->cfg->ops->init_sw_vars() fails.
>
> *BUG 2:
> In rtl_pci_probe(), rtl_init_core() can fail when rtl_regd_init() in
> this function fails, and rtlpriv->scan_list.list has not been
> initialized by INIT_LIST_HEAD(). Then, rtl_deinit_core() in the error
> handling code of rtl_pci_probe() is executed. Finally, a null-pointer
> dereference occurs due to the same reason of the above bug.
>
> To fix this bug, the initialization of lists in rtl_init_core() are
> performed before the call to rtl_regd_init().
>
> These bugs are found by a runtime fuzzing tool named FIZZER written by
> us.
>
> Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>

Ping & Larry, is this ok to take?

--
https://patchwork.kernel.org/patch/10942971/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches