| Message ID | 20230131070552.115067-1-xiaodong.liu@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | block: ublk: extending queue_size to fix overflow | expand |
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
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,
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;
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(-)