Patch "nbd: use loff_t for blocksize and nbd_set_size args" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

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

    nbd: use loff_t for blocksize and nbd_set_size args

to the 4.9-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:
     nbd-use-loff_t-for-blocksize-and-nbd_set_size-args.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From ef77b515243b3499d62cf446eda6ca7e0a0b079c Mon Sep 17 00:00:00 2001
From: Josef Bacik <jbacik@fb.com>
Date: Fri, 2 Dec 2016 16:19:12 -0500
Subject: nbd: use loff_t for blocksize and nbd_set_size args

From: Josef Bacik <jbacik@fb.com>

commit ef77b515243b3499d62cf446eda6ca7e0a0b079c upstream.

If we have large devices (say like the 40t drive I was trying to test with) we
will end up overflowing the int arguments to nbd_set_size and not get the right
size for our device.  Fix this by using loff_t everywhere so I don't have to
think about this again.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/block/nbd.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -54,7 +54,7 @@ struct nbd_device {
 
 	struct mutex tx_lock;
 	struct gendisk *disk;
-	int blksize;
+	loff_t blksize;
 	loff_t bytesize;
 
 	/* protects initialization and shutdown of the socket */
@@ -126,7 +126,7 @@ static void nbd_size_update(struct nbd_d
 }
 
 static int nbd_size_set(struct nbd_device *nbd, struct block_device *bdev,
-			int blocksize, int nr_blocks)
+			loff_t blocksize, loff_t nr_blocks)
 {
 	int ret;
 
@@ -135,7 +135,7 @@ static int nbd_size_set(struct nbd_devic
 		return ret;
 
 	nbd->blksize = blocksize;
-	nbd->bytesize = (loff_t)blocksize * (loff_t)nr_blocks;
+	nbd->bytesize = blocksize * nr_blocks;
 
 	nbd_size_update(nbd, bdev);
 
@@ -817,7 +817,7 @@ static int nbd_dev_dbg_init(struct nbd_d
 	debugfs_create_file("tasks", 0444, dir, nbd, &nbd_dbg_tasks_ops);
 	debugfs_create_u64("size_bytes", 0444, dir, &nbd->bytesize);
 	debugfs_create_u32("timeout", 0444, dir, &nbd->tag_set.timeout);
-	debugfs_create_u32("blocksize", 0444, dir, &nbd->blksize);
+	debugfs_create_u64("blocksize", 0444, dir, &nbd->blksize);
 	debugfs_create_file("flags", 0444, dir, nbd, &nbd_dbg_flags_ops);
 
 	return 0;


Patches currently in stable-queue which might be from jbacik@fb.com are

queue-4.9/nbd-use-loff_t-for-blocksize-and-nbd_set_size-args.patch