Kees Cook <[email protected]> wrote:
> After commit e3eac9f32ec0 ("wifi: cfg80211: Annotate struct
> cfg80211_scan_request with __counted_by"), the compiler may enforce
> dynamic array indexing of req->channels to stay below n_channels. As a
> result, n_channels needs to be increased _before_ accessing the newly
> added array index. Increment it first, then use "i" for the prior index.
> Solves this warning in the coming GCC that has __counted_by support:
>
> ../drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c: In function 'brcmf_internal_escan_add_info':
> ../drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c:3783:46: warning: operation on 'req->
> n_channels' may be undefined [-Wsequence-point]
> 3783 | req->channels[req->n_channels++] = chan;
> | ~~~~~~~~~~~~~~~^~
>
> Fixes: e3eac9f32ec0 ("wifi: cfg80211: Annotate struct cfg80211_scan_request with __counted_by")
> Cc: Arend van Spriel <[email protected]>
> Cc: Franky Lin <[email protected]>
> Cc: Hante Meuleman <[email protected]>
> Cc: Kalle Valo <[email protected]>
> Cc: Chi-hsien Lin <[email protected]>
> Cc: Ian Lin <[email protected]>
> Cc: Johannes Berg <[email protected]>
> Cc: Wright Feng <[email protected]>
> Cc: Hector Martin <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>
> Reviewed-by: Hans de Goede <[email protected]>
> Reviewed-by: Linus Walleij <[email protected]>
> Reviewed-by: Gustavo A. R. Silva <[email protected]>
I'm planning to queue this for wireless tree. Arend, ack?
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