[GIT PULL] SCSI fixes for 2.6.39-rc5

From: James Bottomley
Date: Fri Apr 29 2011 - 14:14:03 EST


This is a set of assorted fixes including a couple of user induceable
oopses using card interfaces. The main one is closing a race between
the last put of a device and the queues starting up, which has been
there for ages, but only just started to show.

The patch is available here:

master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6.git

The short changelog is:

Dan Rosenberg (2):
pmcraid: reject negative request size
mpt2sas: prevent heap overflows and unchecked reads

James Bottomley (1):
put stricter guards on queue dead checks

Mike Snitzer (1):
scsi_dh: fix reference counting in scsi_dh_activate error path

The diffstat is:

drivers/scsi/device_handler/scsi_dh.c | 9 ++++++---
drivers/scsi/mpt2sas/mpt2sas_ctl.c | 23 +++++++++++++++++++++--
drivers/scsi/pmcraid.c | 3 +++
drivers/scsi/scsi_sysfs.c | 16 ++++++++--------
4 files changed, 38 insertions(+), 13 deletions(-)

and the full patch is appended.

James

---

diff --git a/drivers/scsi/device_handler/scsi_dh.c b/drivers/scsi/device_handler/scsi_dh.c
index 564e6ec..0119b81 100644
--- a/drivers/scsi/device_handler/scsi_dh.c
+++ b/drivers/scsi/device_handler/scsi_dh.c
@@ -394,12 +394,14 @@ int scsi_dh_activate(struct request_queue *q, activate_complete fn, void *data)
unsigned long flags;
struct scsi_device *sdev;
struct scsi_device_handler *scsi_dh = NULL;
+ struct device *dev = NULL;

spin_lock_irqsave(q->queue_lock, flags);
sdev = q->queuedata;
if (sdev && sdev->scsi_dh_data)
scsi_dh = sdev->scsi_dh_data->scsi_dh;
- if (!scsi_dh || !get_device(&sdev->sdev_gendev) ||
+ dev = get_device(&sdev->sdev_gendev);
+ if (!scsi_dh || !dev ||
sdev->sdev_state == SDEV_CANCEL ||
sdev->sdev_state == SDEV_DEL)
err = SCSI_DH_NOSYS;
@@ -410,12 +412,13 @@ int scsi_dh_activate(struct request_queue *q, activate_complete fn, void *data)
if (err) {
if (fn)
fn(data, err);
- return err;
+ goto out;
}

if (scsi_dh->activate)
err = scsi_dh->activate(sdev, fn, data);
- put_device(&sdev->sdev_gendev);
+out:
+ put_device(dev);
return err;
}
EXPORT_SYMBOL_GPL(scsi_dh_activate);
diff --git a/drivers/scsi/mpt2sas/mpt2sas_ctl.c b/drivers/scsi/mpt2sas/mpt2sas_ctl.c
index 1c6d2b4..d72f1f2 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_ctl.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_ctl.c
@@ -688,6 +688,13 @@ _ctl_do_mpt_command(struct MPT2SAS_ADAPTER *ioc,
goto out;
}

+ /* Check for overflow and wraparound */
+ if (karg.data_sge_offset * 4 > ioc->request_sz ||
+ karg.data_sge_offset > (UINT_MAX / 4)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
/* copy in request message frame from user */
if (copy_from_user(mpi_request, mf, karg.data_sge_offset*4)) {
printk(KERN_ERR "failure at %s:%d/%s()!\n", __FILE__, __LINE__,
@@ -1963,7 +1970,7 @@ _ctl_diag_read_buffer(void __user *arg, enum block_state state)
Mpi2DiagBufferPostReply_t *mpi_reply;
int rc, i;
u8 buffer_type;
- unsigned long timeleft;
+ unsigned long timeleft, request_size, copy_size;
u16 smid;
u16 ioc_status;
u8 issue_reset = 0;
@@ -1999,6 +2006,8 @@ _ctl_diag_read_buffer(void __user *arg, enum block_state state)
return -ENOMEM;
}

+ request_size = ioc->diag_buffer_sz[buffer_type];
+
if ((karg.starting_offset % 4) || (karg.bytes_to_read % 4)) {
printk(MPT2SAS_ERR_FMT "%s: either the starting_offset "
"or bytes_to_read are not 4 byte aligned\n", ioc->name,
@@ -2006,13 +2015,23 @@ _ctl_diag_read_buffer(void __user *arg, enum block_state state)
return -EINVAL;
}

+ if (karg.starting_offset > request_size)
+ return -EINVAL;
+
diag_data = (void *)(request_data + karg.starting_offset);
dctlprintk(ioc, printk(MPT2SAS_INFO_FMT "%s: diag_buffer(%p), "
"offset(%d), sz(%d)\n", ioc->name, __func__,
diag_data, karg.starting_offset, karg.bytes_to_read));

+ /* Truncate data on requests that are too large */
+ if ((diag_data + karg.bytes_to_read < diag_data) ||
+ (diag_data + karg.bytes_to_read > request_data + request_size))
+ copy_size = request_size - karg.starting_offset;
+ else
+ copy_size = karg.bytes_to_read;
+
if (copy_to_user((void __user *)uarg->diagnostic_data,
- diag_data, karg.bytes_to_read)) {
+ diag_data, copy_size)) {
printk(MPT2SAS_ERR_FMT "%s: Unable to write "
"mpt_diag_read_buffer_t data @ %p\n", ioc->name,
__func__, diag_data);
diff --git a/drivers/scsi/pmcraid.c b/drivers/scsi/pmcraid.c
index 96d5ad0..7f636b1 100644
--- a/drivers/scsi/pmcraid.c
+++ b/drivers/scsi/pmcraid.c
@@ -3814,6 +3814,9 @@ static long pmcraid_ioctl_passthrough(
rc = -EFAULT;
goto out_free_buffer;
}
+ } else if (request_size < 0) {
+ rc = -EINVAL;
+ goto out_free_buffer;
}

/* check if we have any additional command parameters */
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index e44ff64..e639125 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -322,14 +322,8 @@ static void scsi_device_dev_release_usercontext(struct work_struct *work)
kfree(evt);
}

- if (sdev->request_queue) {
- sdev->request_queue->queuedata = NULL;
- /* user context needed to free queue */
- scsi_free_queue(sdev->request_queue);
- /* temporary expedient, try to catch use of queue lock
- * after free of sdev */
- sdev->request_queue = NULL;
- }
+ /* NULL queue means the device can't be used */
+ sdev->request_queue = NULL;

scsi_target_reap(scsi_target(sdev));

@@ -937,6 +931,12 @@ void __scsi_remove_device(struct scsi_device *sdev)
if (sdev->host->hostt->slave_destroy)
sdev->host->hostt->slave_destroy(sdev);
transport_destroy_device(dev);
+
+ /* cause the request function to reject all I/O requests */
+ sdev->request_queue->queuedata = NULL;
+
+ /* Freeing the queue signals to block that we're done */
+ scsi_free_queue(sdev->request_queue);
put_device(dev);
}



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