Re: [PATCH] wifi: brcm80211: handle pmk_op allocation failure

From: Joe Perches
Date: Tue Feb 27 2024 - 14:58:55 EST


On Tue, 2024-02-27 at 20:40 +0100, Arend van Spriel wrote:
> On 2/27/2024 12:42 PM, Joe Perches wrote:
> > On Tue, 2024-02-27 at 12:21 +0100, Arend van Spriel wrote:
> > > On 2/27/2024 9:06 AM, Duoming Zhou wrote:
> > > > The kzalloc() in brcmf_pmksa_v3_op() will return null if the
> > > > physical memory has run out. As a result, if we dereference
> > > > the null value, the null pointer dereference bug will happen.
> > > >
> > > > Return -ENOMEM from brcmf_pmksa_v3_op() if kzalloc() fails
> > > > for pmk_op.
> > >
> > > NAK (see below)
> > >
> > > Also this issue was reported earlier by Joe Perches. Not sure if he
> > > wants to be mentioned as such.
> >
> > I think it's unimportant to be mentioned.
> >
> > I think it's more important that the code be researched
> > that the simple return of -ENOMEM the appropriate fix
> > and is handled by all possible callers of the function.
>
> Right. That is what I did after which I replied on Feb 18 to your email.
>
> https://lore.kernel.org/all/3e1f11b3-a689-4c8e-bfda-b43649db7106@broadcomcom/
>

Right, I did that as well, but I didn't look up
the entire calling tree.

It likely works. It's also likely better than
the write through of the null pointer.