This issue was found and also debugged by Carl Lei <me@xxxxxxxxxxxx>.
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: 34bd1dcacf0d ("scsi: target: Detect UNMAP support post configuration")
Reported-by: Carl Lei <me@xxxxxxxxxxxx>
Signed-off-by: Mike Christie <michael.christie@xxxxxxxxxx>
---
v2: Fix missing configure_unmap handling so failure is returned.
drivers/target/target_core_configfs.c | 48 ++++++++++++++++++---------
1 file changed, 32 insertions(+), 16 deletions(-)
diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c
index a5f58988130a..c1fbcdd16182 100644
--- a/drivers/target/target_core_configfs.c
+++ b/drivers/target/target_core_configfs.c
@@ -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",
--
2.34.1
