On 04/14/2019 01:44 PM, David Miller wrote:
> From: Eric Dumazet <eduma...@google.com>
> Date: Sat, 13 Apr 2019 17:32:21 -0700
>
>> fib_compute_spec_dst() needs to be called under rcu protection.
>>
>> syzbot reported :
> ...
>> Fixes: ed0de45a1008 ("ipv4: recompile ip options in ipv4_link_failure")
>> Signed-off-by: Eric Dumazet <eduma...@google.com>
>> Reported-by: syzbot <syzkal...@googlegroups.com>
>
> Applied, thanks Eric.
>
> Please take a look at the cipso_v4_error case.
>
I am not familiar of this code, but it looks like it runs from BH rx handler,
with rcu_read_lock() asserted.
The problem for ipv4_link_failure() is that it can be run from a timer handler,
which does not generally hold rcu_read_lock().
