Re: [PATCH v2] wifi: brcmfmac: Replace 1-element arrays with flexible arrays

[Kees Cook]

On Thu, Sep 14, 2023 at 09:02:27AM +0200, Juerg Haefliger wrote:
> Since commit 2d47c6956ab3 ("ubsan: Tighten UBSAN_BOUNDS on GCC"),
> UBSAN_BOUNDS no longer pretends 1-element arrays are unbounded. Walking
> 'element' and 'channel_list' will trigger warnings, so make them proper
> flexible arrays.
> 
> False positive warnings were:
> 
>   UBSAN: array-index-out-of-bounds in drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c:6984:20
>   index 1 is out of range for type '__le32 [1]'
> 
>   UBSAN: array-index-out-of-bounds in drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c:1126:27
>   index 1 is out of range for type '__le16 [1]'
> 
> for these lines of code:
> 
>   6884  ch.chspec = (u16)le32_to_cpu(list->element[i]);
> 
>   1126  params_le->channel_list[i] = cpu_to_le16(chanspec);
> 
> Cc: stable@xxxxxxxxxxxxxxx # 6.5+
> Signed-off-by: Juerg Haefliger <juerg.haefliger@xxxxxxxxxxxxx>

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

-- 
Kees Cook