* [PATCH] block: ublk: extending queue_size to fix overflow
@ 2023-01-31 7:05 Liu Xiaodong
2023-01-31 10:15 ` Ming Lei
2023-01-31 14:59 ` Jens Axboe
0 siblings, 2 replies; 3+ messages in thread
From: Liu Xiaodong @ 2023-01-31 7:05 UTC (permalink / raw)
To: Ming Lei, Jens Axboe
Cc: linux-block, linux-kernel, Liu Xiaodong, Jim Harris, Ben Walker
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.
Extend queue_size in ublk_device as "unsigned int".
Signed-off-by: Liu Xiaodong <xiaodong.liu@intel.com>
---
drivers/block/ublk_drv.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index e54693204630..6368b56eacf1 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -137,7 +137,7 @@ struct ublk_device {
char *__queues;
- unsigned short queue_size;
+ unsigned int queue_size;
struct ublksrv_ctrl_dev_info dev_info;
struct blk_mq_tag_set tag_set;
--
2.14.5
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] block: ublk: extending queue_size to fix overflow
2023-01-31 7:05 [PATCH] block: ublk: extending queue_size to fix overflow Liu Xiaodong
@ 2023-01-31 10:15 ` Ming Lei
2023-01-31 14:59 ` Jens Axboe
1 sibling, 0 replies; 3+ messages in thread
From: Ming Lei @ 2023-01-31 10:15 UTC (permalink / raw)
To: Liu Xiaodong
Cc: Jens Axboe, linux-block, linux-kernel, Jim Harris, Ben Walker
On Tue, Jan 31, 2023 at 02:05:52AM -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.
>
> Extend queue_size in ublk_device as "unsigned int".
>
> Signed-off-by: Liu Xiaodong <xiaodong.liu@intel.com>
> ---
> drivers/block/ublk_drv.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
> index e54693204630..6368b56eacf1 100644
> --- a/drivers/block/ublk_drv.c
> +++ b/drivers/block/ublk_drv.c
> @@ -137,7 +137,7 @@ struct ublk_device {
>
> char *__queues;
>
> - unsigned short queue_size;
> + unsigned int queue_size;
> struct ublksrv_ctrl_dev_info dev_info;
Good catch,
Fixes: 71f28f3136af ("ublk_drv: add io_uring based userspace block driver")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Thanks,
Ming
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] block: ublk: extending queue_size to fix overflow
2023-01-31 7:05 [PATCH] block: ublk: extending queue_size to fix overflow Liu Xiaodong
2023-01-31 10:15 ` Ming Lei
@ 2023-01-31 14:59 ` Jens Axboe
1 sibling, 0 replies; 3+ messages in thread
From: Jens Axboe @ 2023-01-31 14:59 UTC (permalink / raw)
To: Ming Lei, Liu Xiaodong; +Cc: linux-block, linux-kernel, Jim Harris, Ben Walker
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
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2023-01-31 15:00 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-01-31 7:05 [PATCH] block: ublk: extending queue_size to fix overflow Liu Xiaodong
2023-01-31 10:15 ` Ming Lei
2023-01-31 14:59 ` Jens Axboe
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).