[PATCH 4.9 56/69] nbd: use loff_t for blocksize and nbd_set_size args

From: Greg Kroah-Hartman
Date: Wed Apr 19 2017 - 10:51:29 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Josef Bacik <jbacik@xxxxxx>

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@xxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxx>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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;