diff options
| author | Moger, Babu <Babu.Moger@netapp.com> | 2011-10-26 14:29:38 -0400 |
|---|---|---|
| committer | Willy Tarreau <w@1wt.eu> | 2012-02-11 15:38:23 +0100 |
| commit | d6cca2359c5b61d5a8ebecc04e4f2a4a074583cd (patch) | |
| tree | 925e11808f2f43de5e2be75726db40c198954399 | |
| parent | 3c890fae7b700976e798999d7c18868e653745e8 (diff) | |
SCSI: scsi_dh: check queuedata pointer before proceeding further
commit a18a920c70d48a8e4a2b750d8a183b3c1a4be514 upstream.
This patch validates sdev pointer in scsi_dh_activate before proceeding further.
Without this check we might see the panic as below. I have seen this
panic multiple times..
Call trace:
#0 [ffff88007d647b50] machine_kexec at ffffffff81020902
#1 [ffff88007d647ba0] crash_kexec at ffffffff810875b0
#2 [ffff88007d647c70] oops_end at ffffffff8139c650
#3 [ffff88007d647c90] __bad_area_nosemaphore at ffffffff8102dd15
#4 [ffff88007d647d50] page_fault at ffffffff8139b8cf
[exception RIP: scsi_dh_activate+0x82]
RIP: ffffffffa0041922 RSP: ffff88007d647e00 RFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000000093c5
RDX: 00000000000093c5 RSI: ffffffffa02e6640 RDI: ffff88007cc88988
RBP: 000000000000000f R8: ffff88007d646000 R9: 0000000000000000
R10: ffff880082293790 R11: 00000000ffffffff R12: ffff88007cc88988
R13: 0000000000000000 R14: 0000000000000286 R15: ffff880037b845e0
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000
#5 [ffff88007d647e38] run_workqueue at ffffffff81060268
#6 [ffff88007d647e78] worker_thread at ffffffff81060386
#7 [ffff88007d647ee8] kthread at ffffffff81064436
#8 [ffff88007d647f48] kernel_thread at ffffffff81003fba
Signed-off-by: Babu Moger <babu.moger@netapp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Willy Tarreau <w@1wt.eu>
| -rw-r--r-- | drivers/scsi/device_handler/scsi_dh.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/scsi/device_handler/scsi_dh.c b/drivers/scsi/device_handler/scsi_dh.c index a518f2eff19a..92feab57521e 100644 --- a/drivers/scsi/device_handler/scsi_dh.c +++ b/drivers/scsi/device_handler/scsi_dh.c @@ -423,7 +423,12 @@ int scsi_dh_activate(struct request_queue *q) spin_lock_irqsave(q->queue_lock, flags); sdev = q->queuedata; - if (sdev && sdev->scsi_dh_data) + if (!sdev) { + spin_unlock_irqrestore(q->queue_lock, flags); + return SCSI_DH_NOSYS; + } + + if (sdev->scsi_dh_data) scsi_dh = sdev->scsi_dh_data->scsi_dh; if (!scsi_dh || !get_device(&sdev->sdev_gendev)) err = SCSI_DH_NOSYS; |