Re: [PATCH net] tls: don't use stack memory in a scatterlist

[David Miller]

From: Matt Mullins 
Date: Thu, 17 May 2018 20:28:46 +

> On Thu, 2018-05-17 at 14:50 -0400, David Miller wrote:
>> I'm surprised this problem wasn't discovered sooner.  How exactly did you
>> discover it?  Did you actually see it trigger or is this purely from code
>> inspection?
> 
> Honestly, I'm not sure how it got uncovered, but it was observed at
> runtime.  Doron Roberts-Kedes hit a null pointer dereference so we
> turned on CONFIG_DEBUG_SG -- then it became a proper
> BUG_ON(!virt_addr_valid(buf)); in sg_set_buf.

Fair enough, thanks for the info.

Re: [PATCH net] tls: don't use stack memory in a scatterlist

[Matt Mullins]

On Thu, 2018-05-17 at 14:50 -0400, David Miller wrote:
> I'm surprised this problem wasn't discovered sooner.  How exactly did you
> discover it?  Did you actually see it trigger or is this purely from code
> inspection?

Honestly, I'm not sure how it got uncovered, but it was observed at
runtime.  Doron Roberts-Kedes hit a null pointer dereference so we
turned on CONFIG_DEBUG_SG -- then it became a proper
BUG_ON(!virt_addr_valid(buf)); in sg_set_buf.

Re: [PATCH net] tls: don't use stack memory in a scatterlist

[David Miller]

From: Matt Mullins 
Date: Wed, 16 May 2018 10:48:40 -0700

> scatterlist code expects virt_to_page() to work, which fails with
> CONFIG_VMAP_STACK=y.
> 
> Fixes: c46234ebb4d1e ("tls: RX path for ktls")
> Signed-off-by: Matt Mullins 

Applied and queued up for -stable, thanks.

I'm surprised this problem wasn't discovered sooner.  How exactly did you
discover it?  Did you actually see it trigger or is this purely from code
inspection?