lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-ID: <8219c79e-0359-4136-afa4-fba76fde191a@embeddedor.com> Date: Tue, 24 Oct 2023 20:37:31 -0600 From: "Gustavo A. R. Silva" <gustavo@...eddedor.com> To: Johannes Berg <johannes@...solutions.net>, Kalle Valo <kvalo@...nel.org>, Jeff Johnson <quic_jjohnson@...cinc.com> Cc: ath10k@...ts.infradead.org, linux-wireless@...r.kernel.org, linux-kernel@...r.kernel.org, "Gustavo A. R. Silva" <gustavoars@...nel.org>, linux-hardening@...r.kernel.org Subject: Re: [RFC - is this a bug?] wifi: ath10k: Asking for some light on this, please :) On 10/24/23 14:49, Johannes Berg wrote: > On Tue, 2023-10-24 at 14:41 -0600, Gustavo A. R. Silva wrote: >> >> It seems we run into the same issue in the function below, even in the >> case this `memset()` is unnecessary (which it seems it's not): >> >> 8920 memset(skb->data, 0, sizeof(*cmd)); >> >> Notice that if `cap->peer_chan_len == 0` or `cap->peer_chan_len == 1`, >> in the original code, we have `len == sizeof(*cmd) == 128`: > > Right. > >> - /* tdls peer update cmd has place holder for one channel*/ >> - chan_len = cap->peer_chan_len ? (cap->peer_chan_len - 1) : 0; >> - >> - len = sizeof(*cmd) + chan_len * sizeof(*chan); >> + len = struct_size(cmd, peer_capab.peer_chan_list, cap->peer_chan_len); >> >> skb = ath10k_wmi_alloc_skb(ar, len); >> if (!skb) >> >> which makes `round_len == roundup(len, 4) == struct_size(cmd,...,...) == 104` >> when `cap->peer_chan_len == 0` > > And yeah, that's really the issue, it only matters for ==0. For a moment > there I thought that doesn't even make sense, but it looks like it never > even becomes non-zero. > > No idea then, sorry. You'd hope firmware doesn't care about the actual > message size if the inner data says "0 entries", but who knows? And how > many firmware versions are there? :) > > So I guess you'd want to stay compatible, even if it means having a > > chan_len = min(cap->peer_chan_len, 1); > > for the struct_size()? Yeah, that's an alternative. I'll wait for the maintainers to chime in and see if they have a different opinion. Thanks -- Gustavo
Powered by blists - more mailing lists