From: Liu Xiaodong Date: Tue, 31 Jan 2023 07:05:52 +0000 (-0500) Subject: block: ublk: extending queue_size to fix overflow X-Git-Tag: baikal/aarch64/sdk6.1~143 X-Git-Url: https://git.baikalelectronics.ru/sdk/?a=commitdiff_plain;h=c08a9eab76d615bc40720fe3aa236b36d415f3ee;p=kernel.git block: ublk: extending queue_size to fix overflow [ Upstream commit 29baef789c838bd5c02f50c88adbbc6b955aaf61 ] 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 Fixes: c72ffe88841a ("ublk_drv: add io_uring based userspace block driver") Reviewed-by: Ming Lei Link: https://lore.kernel.org/r/20230131070552.115067-1-xiaodong.liu@intel.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index e546932046309..6368b56eacf11 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;