| From | Paul Gortmaker <> | Subject | [34-longterm 013/196] ses: Avoid kernel panic when lun 0 is not mapped | Date | Mon, 12 Mar 2012 20:12:21 -0400 |
| |
From: "Krishnasamy, Somasundaram" <Somasundaram.Krishnasamy@lsi.com>
------------------- This is a commit scheduled for the next v2.6.34 longterm release. If you see a problem with using this for longterm, please comment. -------------------
commit d1e12de804f9d8ad114786ca7c2ce593cba79891 upstream.
During device discovery, scsi mid layer sends INQUIRY command to LUN 0. If the LUN 0 is not mapped to host, it creates a temporary scsi_device with LUN id 0 and sends REPORT_LUNS command to it. After the REPORT_LUNS succeeds, it walks through the LUN table and adds each LUN found to sysfs. At the end of REPORT_LUNS lun table scan, it will delete the temporary scsi_device of LUN 0.
When scsi devices are added to sysfs, it calls add_dev function of all the registered class interfaces. If ses driver has been registered, ses_intf_add() of ses module will be called. This function calls scsi_device_enclosure() to check the inquiry data for EncServ bit. Since inquiry was not allocated for temporary LUN 0 scsi_device, it will cause NULL pointer exception.
To fix the problem, sdev->inquiry is checked for NULL before reading it.
Signed-off-by: Somasundaram Krishnasamy <Somasundaram.Krishnasamy@lsi.com> Signed-off-by: Babu Moger <babu.moger@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> --- include/scsi/scsi_device.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index d80b6db..558fa2f 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -451,7 +451,7 @@ static inline int scsi_device_qas(struct scsi_device *sdev) } static inline int scsi_device_enclosure(struct scsi_device *sdev) { - return sdev->inquiry[6] & (1<<6); + return sdev->inquiry ? (sdev->inquiry[6] & (1<<6)) : 1; } static inline int scsi_device_protection(struct scsi_device *sdev) -- 1.7.9.3
|