From:   Jens Axboe <axboe@kernel.dk>
To:     Ming Lei <ming.lei@redhat.com>,
        Liu Xiaodong <xiaodong.liu@intel.com>
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jim Harris <james.r.harris@intel.com>,
        Ben Walker <benjamin.walker@intel.com>
In-Reply-To: <20230131070552.115067-1-xiaodong.liu@intel.com>
References: <20230131070552.115067-1-xiaodong.liu@intel.com>
Subject: Re: [PATCH] block: ublk: extending queue_size to fix overflow
Message-Id: <167517714685.21899.10299241689859963675.b4-ty@kernel.dk>
Date:   Tue, 31 Jan 2023 07:59:06 -0700
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 7bit
Precedence: bulk


On Tue, 31 Jan 2023 02:05:52 -0500, Liu Xiaodong wrote:
> When validating drafted SPDK ublk target, in a case that
> assigning large queue depth to multiqueue ublk device,
> ublk target would run into a weird incorrect state. During
> rounds of review and debug, An overflow bug was found
> in ublk driver.
> 
> In ublk_cmd.h, UBLK_MAX_QUEUE_DEPTH is 4096 which means
> each ublk queue depth can be set as large as 4096. But
> when setting qd for a ublk device,
> sizeof(struct ublk_queue) + depth * sizeof(struct ublk_io)
> will be larger than 65535 if qd is larger than 2728.
> Then queue_size is overflowed, and ublk_get_queue()
> references a wrong pointer position. The wrong content of
> ublk_queue elements will lead to out-of-bounds memory
> access.
> 
> [...]

Applied, thanks!

[1/1] block: ublk: extending queue_size to fix overflow
      commit: 29baef789c838bd5c02f50c88adbbc6b955aaf61

Best regards,
-- 
Jens Axboe