This is a note to let you know that I've just added the patch titled

    target: Fix divide by zero bug in fabric_max_sectors for unconfigured 
devices

to the 3.4-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     
target-fix-divide-by-zero-bug-in-fabric_max_sectors-for-unconfigured-devices.patch
and it can be found in the queue-3.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From [email protected]  Tue Feb 26 10:03:15 2013
From: "Nicholas A. Bellinger" <[email protected]>
Date: Tue, 19 Feb 2013 03:15:14 +0000
Subject: target: Fix divide by zero bug in fabric_max_sectors for unconfigured 
devices
To: target-devel <[email protected]>
Cc: Nicholas Bellinger <[email protected]>, Herton Ronaldo Krzesinski 
<[email protected]>, Greg Kroah-Hartman 
<[email protected]>
Message-ID: <[email protected]>


From: Nicholas Bellinger <[email protected]>

commit 7a3cf6ca1ab2a2f7161c6dec5a787fc7a5de864e upstream

This patch fixes a possible divide by zero bug when the fabric_max_sectors
device attribute is written and backend se_device failed to be successfully
configured -> enabled.

Go ahead and use block_size=512 within se_dev_set_fabric_max_sectors()
in the event of a target_configure_device() failure case, as no valid
dev->dev_attrib.block_size value will have been setup yet.

Signed-off-by: Nicholas Bellinger <[email protected]>
Cc: Herton Ronaldo Krzesinski <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/target/target_core_device.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -1230,6 +1230,8 @@ int se_dev_set_max_sectors(struct se_dev
 
 int se_dev_set_fabric_max_sectors(struct se_device *dev, u32 
fabric_max_sectors)
 {
+       int block_size = dev->se_sub_dev->se_dev_attrib.block_size;
+
        if (atomic_read(&dev->dev_export_obj.obj_access_count)) {
                pr_err("dev[%p]: Unable to change SE Device"
                        " fabric_max_sectors while dev_export_obj: %d count 
exists\n",
@@ -1267,8 +1269,12 @@ int se_dev_set_fabric_max_sectors(struct
        /*
         * Align max_sectors down to PAGE_SIZE to follow 
transport_allocate_data_tasks()
         */
+       if (!block_size) {
+               block_size = 512;
+               pr_warn("Defaulting to 512 for zero block_size\n");
+       }
        fabric_max_sectors = se_dev_align_max_sectors(fabric_max_sectors,
-                                                     
dev->se_sub_dev->se_dev_attrib.block_size);
+                                                     block_size);
 
        dev->se_sub_dev->se_dev_attrib.fabric_max_sectors = fabric_max_sectors;
        pr_debug("dev[%p]: SE Device max_sectors changed to %u\n",


Patches currently in stable-queue which might be from [email protected] are

queue-3.4/target-fix-divide-by-zero-bug-in-fabric_max_sectors-for-unconfigured-devices.patch
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