Re: [PATCH] brcmfmac: buffer overflow in brcmf_cfg80211_mgmt_tx()

On 7/7/2017 10:49 AM, Dan Carpenter wrote:

On Fri, Jul 07, 2017 at 11:40:26AM +0300, Kalle Valo wrote:

quoted

Linus Torvalds [off-list ref] writes:

quoted

On Thu, Jul 6, 2017 at 10:11 AM, Arend van Spriel
[off-list ref] wrote:

quoted

Looks fine to me so ...

I really think that if we can't trust 'len', then we have to check
against the lower bound of DOT11_MGMT_HDR_LEN too, because otherwise
we'll just have a big 16-bit number instead.

And we should do that brcmf_err() that I had in my version, which also
let's people know they are being attacked.

I hope brcmf_err() is ratelimited so that the attacker cannot spam the
logs too much.

The attacker already has CAP_NET_ADMIN here so you're probably already
toasted.

Indeed and brcmf_err() is ratelimited when build without CONFIG_BRCMDBG, 
which is what distros typically do.

Regards,
Arend