Re: [PATCH] scsi: ses: Fix crash caused by kfree an invalid pointer

---8>8>8><8<8<8--------
From: James Bottomley <James.Bottomley@HansenPartnership.com>
Subject: [PATCH] scsi: ses: don't attach if enclosure has no components

An enclosure with no components can't usefully be operated by the
driver (since effectively it has nothing to manage), so report the
problem and don't attach.  Not attaching also fixes an oops which
could occur if the driver tries to manage a zero component enclosure.

Reported-by: Ding Hui <redacted>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
---
  drivers/scsi/ses.c | 5 +++++
  1 file changed, 5 insertions(+)

diff --git a/drivers/scsi/ses.c b/drivers/scsi/ses.c
index c2afba2a5414..9624298b9c89 100644
--- a/drivers/scsi/ses.c
+++ b/drivers/scsi/ses.c

@@ -690,6 +690,11 @@ static int ses_intf_add(struct device *cdev,
  		    type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE)
  			components += type_ptr[1];
  	}
+	if (components == 0) {
+		sdev_printk(KERN_ERR, sdev, "enclosure has no enumerated components\n");
+		goto err_free;
+	}
+
  	ses_dev->page1 = buf;
  	ses_dev->page1_len = len;
  	buf = NULL;