[PATCH 4.14 44/95] mmc: block: Check return value of blk_get_request()

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Adrian Hunter <adrian.hunter@xxxxxxxxx>

commit fb8e456e547ed2c699f64665bd8a3b9bde7b9728 upstream.

blk_get_request() can fail, always check the return value.

Fixes: 0493f6fe5bde ("mmc: block: Move boot partition locking into a driver op")
Fixes: 3ecd8cf23f88 ("mmc: block: move multi-ioctl() to use block layer")
Fixes: 614f0388f580 ("mmc: block: move single ioctl() commands to block requests")
Fixes: 627c3ccfb46a ("mmc: debugfs: Move block debugfs into block module")
Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/mmc/core/block.c |   20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -204,6 +204,10 @@ static ssize_t power_ro_lock_store(struc
 
 	/* Dispatch locking to the block layer */
 	req = blk_get_request(mq->queue, REQ_OP_DRV_OUT, __GFP_RECLAIM);
+	if (IS_ERR(req)) {
+		count = PTR_ERR(req);
+		goto out_put;
+	}
 	req_to_mmc_queue_req(req)->drv_op = MMC_DRV_OP_BOOT_WP;
 	blk_execute_rq(mq->queue, NULL, req, 0);
 	ret = req_to_mmc_queue_req(req)->drv_op_result;
@@ -220,7 +224,7 @@ static ssize_t power_ro_lock_store(struc
 				set_disk_ro(part_md->disk, 1);
 			}
 	}
-
+out_put:
 	mmc_blk_put(md);
 	return count;
 }
@@ -581,6 +585,10 @@ static int mmc_blk_ioctl_cmd(struct mmc_
 	req = blk_get_request(mq->queue,
 		idata->ic.write_flag ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN,
 		__GFP_RECLAIM);
+	if (IS_ERR(req)) {
+		err = PTR_ERR(req);
+		goto cmd_done;
+	}
 	idatas[0] = idata;
 	req_to_mmc_queue_req(req)->drv_op = MMC_DRV_OP_IOCTL;
 	req_to_mmc_queue_req(req)->drv_op_data = idatas;
@@ -644,6 +652,10 @@ static int mmc_blk_ioctl_multi_cmd(struc
 	req = blk_get_request(mq->queue,
 		idata[0]->ic.write_flag ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN,
 		__GFP_RECLAIM);
+	if (IS_ERR(req)) {
+		err = PTR_ERR(req);
+		goto cmd_err;
+	}
 	req_to_mmc_queue_req(req)->drv_op = MMC_DRV_OP_IOCTL;
 	req_to_mmc_queue_req(req)->drv_op_data = idata;
 	req_to_mmc_queue_req(req)->ioc_count = num_of_cmds;
@@ -2315,6 +2327,8 @@ static int mmc_dbg_card_status_get(void
 
 	/* Ask the block layer about the card status */
 	req = blk_get_request(mq->queue, REQ_OP_DRV_IN, __GFP_RECLAIM);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
 	req_to_mmc_queue_req(req)->drv_op = MMC_DRV_OP_GET_CARD_STATUS;
 	blk_execute_rq(mq->queue, NULL, req, 0);
 	ret = req_to_mmc_queue_req(req)->drv_op_result;
@@ -2349,6 +2363,10 @@ static int mmc_ext_csd_open(struct inode
 
 	/* Ask the block layer for the EXT CSD */
 	req = blk_get_request(mq->queue, REQ_OP_DRV_IN, __GFP_RECLAIM);
+	if (IS_ERR(req)) {
+		err = PTR_ERR(req);
+		goto out_free;
+	}
 	req_to_mmc_queue_req(req)->drv_op = MMC_DRV_OP_GET_EXT_CSD;
 	req_to_mmc_queue_req(req)->drv_op_data = &ext_csd;
 	blk_execute_rq(mq->queue, NULL, req, 0);