> Initialize lenvar = 1 in ca8210_get_ed() and return
> IEEE802154_SYSTEM_ERROR in hwme_get_request_sync() if
> response.pdata.hwme_get_cnf.hw_attribute_length exceeds
> *hw_attribute_length.
The relationship is not obvious to me.
> Tested in QEMU with KASAN enabled by passing an oversized
> hw_attribute_length response into ca8210_get_ed().
>
> Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver")
> Cc: [email protected]
> Assisted-by: LLM
> Signed-off-by: Hui Peng <[email protected]>
> ---
> Changes in v3:
> - No changes.
>
> Changes in v2:
> - Split out as patch 2/3.
> - Replaced the temporary stack buffer in ca8210_get_ed() with lenvar = 1
> and an upper-bound check against *hw_attribute_length in
> hwme_get_request_sync() as requested by Miquel Raynal.
>
> drivers/net/ieee802154/ca8210.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c
> index a990a0f..8aa7ffe 100644
> --- a/drivers/net/ieee802154/ca8210.c
> +++ b/drivers/net/ieee802154/ca8210.c
> @@ -1677,6 +1677,9 @@ static u8 hwme_get_request_sync(
> return IEEE802154_SYSTEM_ERROR;
>
> if (response.pdata.hwme_get_cnf.status == IEEE802154_SUCCESS) {
> + if (response.pdata.hwme_get_cnf.hw_attribute_length >
> + *hw_attribute_length)
> + return IEEE802154_SYSTEM_ERROR;
Why is hw_attribute_length use here before being set (or re-set) just
below?
The organization of this patch is weird.
Miquèl
