[PATCH 4.4 29/57] scsi: core: Put .shost_dev in failure path if host state changes to RUNNING

From: Sasha Levin
Date: Mon Jun 28 2021 - 11:28:35 EST


From: Ming Lei <ming.lei@xxxxxxxxxx>

[ Upstream commit 11714026c02d613c30a149c3f4c4a15047744529 ]

scsi_host_dev_release() only frees dev_name when host state is
SHOST_CREATED. After host state has changed to SHOST_RUNNING,
scsi_host_dev_release() no longer cleans up.

Fix this by doing a put_device(&shost->shost_dev) in the failure path when
host state is SHOST_RUNNING. Move get_device(&shost->shost_gendev) before
device_add(&shost->shost_dev) so that scsi_host_cls_release() can do a put
on this reference.

Link: https://lore.kernel.org/r/20210602133029.2864069-4-ming.lei@xxxxxxxxxx
Cc: Bart Van Assche <bvanassche@xxxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxx>
Reported-by: John Garry <john.garry@xxxxxxxxxx>
Tested-by: John Garry <john.garry@xxxxxxxxxx>
Reviewed-by: John Garry <john.garry@xxxxxxxxxx>
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/scsi/hosts.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index fb4b6034f644..636548030046 100644
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -259,12 +259,11 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,

device_enable_async_suspend(&shost->shost_dev);

+ get_device(&shost->shost_gendev);
error = device_add(&shost->shost_dev);
if (error)
goto out_del_gendev;

- get_device(&shost->shost_gendev);
-
if (shost->transportt->host_size) {
shost->shost_data = kzalloc(shost->transportt->host_size,
GFP_KERNEL);
@@ -300,6 +299,11 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
out_del_dev:
device_del(&shost->shost_dev);
out_del_gendev:
+ /*
+ * Host state is SHOST_RUNNING so we have to explicitly release
+ * ->shost_dev.
+ */
+ put_device(&shost->shost_dev);
device_del(&shost->shost_gendev);
out_destroy_freelist:
scsi_destroy_command_freelist(shost);
--
2.30.2