linux/drivers/scsi/bnx2i
Eddie Wai a878185c3b [SCSI] bnx2i: Fixed kernel panic caused by unprotected task->sc->request deref
During session recovery, the conn_stop call will trigger a flush
to all outstanding SCSI cmds in the xmit queue.  This will set
all outstanding task->sc to NULL prior to the session_teardown
call which frees the task memory.

In the bnx2i SCSI response processing path, only the task was being checked
for NULL under the session lock before the task->sc->request dereferencing.
If there are outstanding SCSI cmd responses pending for process, the
following kernel panic can be exposed where task->sc was found to be NULL.

 Call Trace:
[   69.720205]  [<ffffffffa040d0d0>] bnx2i_process_new_cqes+0x290/0x3c0 [bnx2i]
[   69.804289]  [<ffffffffa040d233>] bnx2i_fastpath_notification+0x33/0xa0 [bnx2
i]
[   69.891490]  [<ffffffffa040d37b>] bnx2i_indicate_kcqe+0xdb/0x330 [bnx2i]
[   69.971427]  [<ffffffffa03eac5e>] service_kcqes+0x16e/0x1d0 [cnic]
[   70.045132]  [<ffffffffa03eacea>] cnic_service_bnx2x_kcq+0x2a/0x50 [cnic]
[   70.126105]  [<ffffffffa03ead53>] cnic_service_bnx2x_bh+0x43/0x140 [cnic]
[   70.207081]  [<ffffffff81060676>] tasklet_action+0x66/0x110
[   70.273521]  [<ffffffff8106025f>] __do_softirq+0xef/0x220
[   70.337887]  [<ffffffff81447ebc>] call_softirq+0x1c/0x30

This patch adds the !task->sc check and also protects the sc dereferencing
under the session lock.

Signed-off-by: Eddie Wai <eddie.wai@broadcom.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-12-14 17:05:23 +04:00
..
57xx_iscsi_constants.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6 2011-07-23 11:13:11 -07:00
57xx_iscsi_hsi.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6 2011-07-23 11:13:11 -07:00
bnx2i_hwi.c [SCSI] bnx2i: Fixed kernel panic caused by unprotected task->sc->request deref 2011-12-14 17:05:23 +04:00
bnx2i_init.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6 2011-07-23 11:13:11 -07:00
bnx2i_iscsi.c [SCSI] iscsi class: sysfs group is_visible callout for iscsi host attrs 2011-08-27 08:36:14 -06:00
bnx2i_sysfs.c [SCSI] bnx2i: Updated copyright and bump version 2011-06-29 16:54:13 -05:00
bnx2i.h broadcom: Move the Broadcom drivers 2011-08-10 19:54:39 -07:00
Kconfig cnic: Fix select dependencies in bnx2fc/bnx2i Kconfig. 2011-08-12 03:00:47 -07:00
Makefile