Re: [PATCH v2 20/30] cxlflash: Correct usage of scsi_host_put()

On Sep 22, 2015, at 3:53 PM, Brian King [off-list ref] =

wrote:

On 09/16/2015 04:30 PM, Matthew R. Ochs wrote:

quoted

Currently, scsi_host_put() is being called prematurely in the
remove path and is missing entirely in an error cleanup path.
The former can lead to memory being freed too early with
subsequent access potentially corrupting data whilst the former
would result in a memory leak.
=20
Move the usage on remove to be the last cleanup action taken
and introduce a call to scsi_host_put() in the one initialization
error path that does not use remove to cleanup.
=20
Signed-off-by: Matthew R. Ochs <redacted>
Signed-off-by: Manoj N. Kumar <redacted>
---
drivers/scsi/cxlflash/main.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
=20

diff --git a/drivers/scsi/cxlflash/main.c =

b/drivers/scsi/cxlflash/main.c

quoted

index fc77cd4..1856a73 100644

--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c

@@ -734,7 +734,6 @@ static void cxlflash_remove(struct pci_dev *pdev)

	case INIT_STATE_SCSI:
		cxlflash_term_local_luns(cfg);
		scsi_remove_host(cfg->host);
-		scsi_host_put(cfg->host);
		/* Fall through */
	case INIT_STATE_AFU:
		term_afu(cfg);

@@ -744,6 +743,7 @@ static void cxlflash_remove(struct pci_dev *pdev)

	case INIT_STATE_NONE:
		flush_work(&cfg->work_q);
		free_mem(cfg);
+		scsi_host_put(cfg->host);
		break;
	}
=20

@@ -2415,6 +2415,7 @@ static int cxlflash_probe(struct pci_dev *pdev,

		dev_err(&pdev->dev, "%s: call to scsi_host_alloc =

failed!\n",

=20
This message text is wrong. Its the call to alloc_mem that has failed =

in this

leg, not the call to scsi_host_alloc.

Good find. I'll fix this in a separate patch.


-matt