lkml.org 
[lkml]   [2012]   [Mar]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[34-longterm 013/196] ses: Avoid kernel panic when lun 0 is not mapped
Date
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


\
 
 \ /
  Last update: 2012-03-13 02:11    [W:0.516 / U:0.176 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site