Re: [BUG] io_uring: defer logic based on shared data
From: Jens Axboe
Date: Fri Oct 25 2019 - 12:09:48 EST
On 10/25/19 10:03 AM, Jens Axboe wrote:
> On 10/25/19 3:55 AM, Pavel Begunkov wrote:
>> I found 2 problems with __io_sequence_defer().
>> 1. it uses @sq_dropped, but doesn't consider @cq_overflow
>> 2. @sq_dropped and @cq_overflow are write-shared with userspace, so
>> it can be maliciously changed.
>> see sent liburing test (test/defer *_hung()), which left an unkillable
>> process for me
> OK, how about the below. I'll split this in two, as it's really two
> separate fixes.
and patch 2:
Let me know what you think, and if/when I can add your reviewed/test-by