Commit 4cbec7e8 authored by Mike Christie's avatar Mike Christie Committed by Martin K. Petersen
Browse files

scsi: target: Fix unmap setup during configuration 



This issue was found and also debugged by Carl Lei <me@xecycle.info>.

If the device is not enabled, iblock/file will have not setup their
se_device to bdev/file mappings. If a user tries to config the unmap
settings at this time, we will then crash trying to access a NULL pointer
where the bdev/file should be.

This patch adds a check to make sure the device is configured before
we try to call the configure_unmap callout.

Fixes: 34bd1dca ("scsi: target: Detect UNMAP support post configuration")
Reported-by: default avatarCarl Lei <me@xecycle.info>
Signed-off-by: default avatarMike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20240209215247.5213-1-michael.christie@oracle.com


Reviewed-by: default avatarMaurizio Lombardi <mlombard@redhat.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 17e94b25

drivers/target/target_core_configfs.c

+32 −16
Original line number Diff line number Diff line
@@ -759,6 +759,29 @@ static ssize_t emulate_tas_store(struct config_item *item, 
	return count;

}



static int target_try_configure_unmap(struct se_device *dev,

				      const char *config_opt)

{

	if (!dev->transport->configure_unmap) {

		pr_err("Generic Block Discard not supported\n");

		return -ENOSYS;

	}



	if (!target_dev_configured(dev)) {

		pr_err("Generic Block Discard setup for %s requires device to be configured\n",

		       config_opt);

		return -ENODEV;

	}



	if (!dev->transport->configure_unmap(dev)) {

		pr_err("Generic Block Discard setup for %s failed\n",

		       config_opt);

		return -ENOSYS;

	}



	return 0;

}



static ssize_t emulate_tpu_store(struct config_item *item,

		const char *page, size_t count)

{
@@ -776,11 +799,9 @@ static ssize_t emulate_tpu_store(struct config_item *item, 
	 * Discard supported is detected iblock_create_virtdevice().

	 */

	if (flag && !da->max_unmap_block_desc_count) {

		if (!dev->transport->configure_unmap ||

		    !dev->transport->configure_unmap(dev)) {

			pr_err("Generic Block Discard not supported\n");

			return -ENOSYS;

		}

		ret = target_try_configure_unmap(dev, "emulate_tpu");

		if (ret)

			return ret;

	}



	da->emulate_tpu = flag;
@@ -806,11 +827,9 @@ static ssize_t emulate_tpws_store(struct config_item *item, 
	 * Discard supported is detected iblock_create_virtdevice().

	 */

	if (flag && !da->max_unmap_block_desc_count) {

		if (!dev->transport->configure_unmap ||

		    !dev->transport->configure_unmap(dev)) {

			pr_err("Generic Block Discard not supported\n");

			return -ENOSYS;

		}

		ret = target_try_configure_unmap(dev, "emulate_tpws");

		if (ret)

			return ret;

	}



	da->emulate_tpws = flag;
@@ -1022,12 +1041,9 @@ static ssize_t unmap_zeroes_data_store(struct config_item *item, 
	 * Discard supported is detected iblock_configure_device().

	 */

	if (flag && !da->max_unmap_block_desc_count) {

		if (!dev->transport->configure_unmap ||

		    !dev->transport->configure_unmap(dev)) {

			pr_err("dev[%p]: Thin Provisioning LBPRZ will not be set because max_unmap_block_desc_count is zero\n",

			       da->da_dev);

			return -ENOSYS;

		}

		ret = target_try_configure_unmap(dev, "unmap_zeroes_data");

		if (ret)

			return ret;

	}

	da->unmap_zeroes_data = flag;

	pr_debug("dev[%p]: SE Device Thin Provisioning LBPRZ bit: %d\n",