Re: [PATCH] chcr_ktls: add a defensive NULL check to prevent a possible null-pointer dereference in chcr_ktls_dev_del()

[Tuo Li]

Hi Jakub

On Fri, Jan 9, 2026 at 9:53 AM Jakub Kicinski <kuba@xxxxxxxxxx> wrote:
>
> On Tue,  6 Jan 2026 20:33:02 +0800 Tuo Li wrote:
> > In this function, u_ctx is guarded by an if statement, which indicates that
> > it may be NULL:
> >
> >   u_ctx = tx_info->adap->uld[CXGB4_ULD_KTLS].handle;
> >   if (u_ctx && u_ctx->detach)
> >     return;
> >
> > Consequently, a potential null-pointer dereference may occur when
> > tx_info->tid != -1, as shown below:
> >
> >   if (tx_info->tid != -1) {
> >     ...
> >     xa_erase(&u_ctx->tid_list, tx_info->tid);
> >   }
> >
> > Therefore, add a defensive NULL check to prevent this issue.
>
> There seems to be no locking here.
> It'd take much more to make this code safe, sprinking random ifs
> here and there seem like a waste of time.

Thanks for pointing this out.

Given the lack of proper locking here, I'd rather drop this patch than add
ad-hoc NULL checks.

Thanks for the review,
Tuo