linux-kernel - [PATCH] [251/275] ses: Avoid kernel panic when lun 0 is not mapped

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20110330210817.EE2043E1A05@tassilo.jf.intel.com>
Date:	Wed, 30 Mar 2011 14:08:17 -0700 (PDT)
From:	Andi Kleen <andi@...stfloor.org>
To:	Somasundaram.Krishnasamy@....com, babu.moger@....com,
	James.Bottomley@...e.de, gregkh@...e.de, ak@...ux.intel.com,
	linux-kernel@...r.kernel.org, stable@...nel.org,
	tim.bird@...sony.com
Subject: [PATCH] [251/275] ses: Avoid kernel panic when lun 0 is not mapped

2.6.35-longterm review patch.  If anyone has any objections, please let me know.

------------------
From: Krishnasamy, Somasundaram <Somasundaram.Krishnasamy@....com>

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@....com>
Signed-off-by: Babu Moger <babu.moger@....com>
Signed-off-by: James Bottomley <James.Bottomley@...e.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@...e.de>
Signed-off-by: Andi Kleen <ak@...ux.intel.com>

---
 include/scsi/scsi_device.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-2.6.35.y/include/scsi/scsi_device.h
===================================================================
--- linux-2.6.35.y.orig/include/scsi/scsi_device.h	2011-03-29 22:50:10.926978825 -0700
+++ linux-2.6.35.y/include/scsi/scsi_device.h	2011-03-29 23:03:03.501210582 -0700
@@ -451,7 +451,7 @@
 }
 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)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/