From: Christian Loehle <CLoehle@xxxxxxxxxxxxxx>
commit 003fb0a51162d940f25fc35e70b0996a12c9e08a upstream.
Requests to the mmc layer usually come through a block device IO.
The exceptions are the ioctl interface, RPMB chardev ioctl
and debugfs, which issue their own blk_mq requests through
blk_execute_rq and do not query the BLK_STS error but the
mmcblk-internal drv_op_result. This patch ensures that drv_op_result
defaults to an error and has to be overwritten by the operation
to be considered successful.
The behavior leads to a bug where the request never propagates
the error, e.g. by directly erroring out at mmc_blk_mq_issue_rq if
mmc_blk_part_switch fails. The ioctl caller of the rpmb chardev then
can never see an error (BLK_STS_IOERR, but drv_op_result is unchanged)
and thus may assume that their call executed successfully when it did not.
While always checking the blk_execute_rq return value would be
advised, let's eliminate the error by always setting
drv_op_result as -EIO to be overwritten on success (or other error)
Fixes: 614f0388f580 ("mmc: block: move single ioctl() commands to block requests")
Signed-off-by: Christian Loehle <cloehle@xxxxxxxxxxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/59c17ada35664b818b7bd83752119b2d@xxxxxxxxxxxxxx
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Christian Loehle <cloehle@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mmc/core/block.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -253,6 +253,7 @@ static ssize_t power_ro_lock_store(struc
goto out_put;
}
req_to_mmc_queue_req(req)->drv_op = MMC_DRV_OP_BOOT_WP;
+ req_to_mmc_queue_req(req)->drv_op_result = -EIO;
blk_execute_rq(mq->queue, NULL, req, 0);
ret = req_to_mmc_queue_req(req)->drv_op_result;
blk_put_request(req);
@@ -638,6 +639,7 @@ static int mmc_blk_ioctl_cmd(struct mmc_
idatas[0] = idata;
req_to_mmc_queue_req(req)->drv_op =
rpmb ? MMC_DRV_OP_IOCTL_RPMB : MMC_DRV_OP_IOCTL;
+ req_to_mmc_queue_req(req)->drv_op_result = -EIO;
req_to_mmc_queue_req(req)->drv_op_data = idatas;
req_to_mmc_queue_req(req)->ioc_count = 1;
blk_execute_rq(mq->queue, NULL, req, 0);
@@ -707,6 +709,7 @@ static int mmc_blk_ioctl_multi_cmd(struc
}
req_to_mmc_queue_req(req)->drv_op =
rpmb ? MMC_DRV_OP_IOCTL_RPMB : MMC_DRV_OP_IOCTL;
+ req_to_mmc_queue_req(req)->drv_op_result = -EIO;
req_to_mmc_queue_req(req)->drv_op_data = idata;
req_to_mmc_queue_req(req)->ioc_count = num_of_cmds;
blk_execute_rq(mq->queue, NULL, req, 0);
@@ -2749,6 +2752,7 @@ static int mmc_dbg_card_status_get(void
if (IS_ERR(req))
return PTR_ERR(req);
req_to_mmc_queue_req(req)->drv_op = MMC_DRV_OP_GET_CARD_STATUS;
+ req_to_mmc_queue_req(req)->drv_op_result = -EIO;
blk_execute_rq(mq->queue, NULL, req, 0);
ret = req_to_mmc_queue_req(req)->drv_op_result;
if (ret >= 0) {
@@ -2787,6 +2791,7 @@ static int mmc_ext_csd_open(struct inode
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_result = -EIO;
req_to_mmc_queue_req(req)->drv_op_data = &ext_csd;
blk_execute_rq(mq->queue, NULL, req, 0);
err = req_to_mmc_queue_req(req)->drv_op_result;
