On Wed, 2018-03-07 at 11:24 -0800, Greg Hackmann wrote:
> f7c83bcbfaf5 ("net: xfrm: use __this_cpu_read per-cpu helper") added
> a
> __this_cpu_read() call inside ipcomp_alloc_tfms(). Since this call
> was
> introduced, the rules around per-cpu accessors have been tightened
> and
> __this_cpu_read() cannot be used in a preemptible context.
>
> syzkaller reported this leading to the following kernel BUG while
> fuzzing sendmsg:
>
>
> Cc: sta...@vger.kernel.org
Hi Greg, thanks for this patch.
1) Please read Documentation/networking/netdev-FAQ.txt
around line 133
2) If you believe this needs to be backported, you must provide
a Fixes: tag to clearly identify commit that changed the behavior.
Otherwise dozens of stable teams will have to figure out by themselves,
wasting precious time.
Thanks.
