[PATCH 09/78] nbd: validate the block size in nbd_set_size

Christoph Hellwig
2020-11-16T14:58:58Z

Move the validation of the block from the callers into nbd_set_size.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
---
drivers/block/nbd.c | 47 +++++++++++++++------------------------------
1 file changed, 15 insertions(+), 32 deletions(-)

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 6e8f2ff715c661..7478a5e02bc1ed 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -296,16 +296,21 @@ static void nbd_size_clear(struct nbd_device *nbd)
}
}

-static void nbd_set_size(struct nbd_device *nbd, loff_t bytesize,
+static int nbd_set_size(struct nbd_device *nbd, loff_t bytesize,
loff_t blksize)
{
struct block_device *bdev;

+ if (!blksize)
+ blksize = NBD_DEF_BLKSIZE;
+ if (blksize < 512 || blksize > PAGE_SIZE || !is_power_of_2(blksize))
+ return -EINVAL;
+
nbd->config->bytesize = bytesize;
nbd->config->blksize = blksize;

if (!nbd->task_recv)
- return;
+ return 0;

if (nbd->config->flags & NBD_FLAG_SEND_TRIM) {
nbd->disk->queue->limits.discard_granularity = blksize;
@@ -325,6 +330,7 @@ static void nbd_set_size(struct nbd_device *nbd, loff_t bytesize,
bdput(bdev);
}
kobject_uevent(&nbd_to_dev(nbd)->kobj, KOBJ_CHANGE);
+ return 0;
}

static void nbd_complete_rq(struct request *req)
@@ -1304,8 +1310,7 @@ static int nbd_start_device(struct nbd_device *nbd)
args->index = i;
queue_work(nbd->recv_workq, &args->work);
}
- nbd_set_size(nbd, config->bytesize, config->blksize);
- return error;
+ return nbd_set_size(nbd, config->bytesize, config->blksize);
}

static int nbd_start_device_ioctl(struct nbd_device *nbd, struct block_device *bdev)
@@ -1347,14 +1352,6 @@ static void nbd_clear_sock_ioctl(struct nbd_device *nbd,
nbd_config_put(nbd);
}

-static bool nbd_is_valid_blksize(unsigned long blksize)
-{
- if (!blksize || !is_power_of_2(blksize) || blksize < 512 ||
- blksize > PAGE_SIZE)
- return false;
- return true;
-}
-
static void nbd_set_cmd_timeout(struct nbd_device *nbd, u64 timeout)
{
nbd->tag_set.timeout = timeout * HZ;
@@ -1379,19 +1376,12 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
case NBD_SET_SOCK:
return nbd_add_socket(nbd, arg, false);
case NBD_SET_BLKSIZE:
- if (!arg)
- arg = NBD_DEF_BLKSIZE;
- if (!nbd_is_valid_blksize(arg))
- return -EINVAL;
- nbd_set_size(nbd, config->bytesize, arg);
- return 0;
+ return nbd_set_size(nbd, config->bytesize, arg);
case NBD_SET_SIZE:
- nbd_set_size(nbd, arg, config->blksize);
- return 0;
+ return nbd_set_size(nbd, arg, config->blksize);
case NBD_SET_SIZE_BLOCKS:
- nbd_set_size(nbd, arg * config->blksize,
- config->blksize);
- return 0;
+ return nbd_set_size(nbd, arg * config->blksize,
+ config->blksize);
case NBD_SET_TIMEOUT:
nbd_set_cmd_timeout(nbd, arg);
return 0;
@@ -1809,18 +1799,11 @@ static int nbd_genl_size_set(struct genl_info *info, struct nbd_device *nbd)
if (info->attrs[NBD_ATTR_SIZE_BYTES])
bytes = nla_get_u64(info->attrs[NBD_ATTR_SIZE_BYTES]);

- if (info->attrs[NBD_ATTR_BLOCK_SIZE_BYTES]) {
+ if (info->attrs[NBD_ATTR_BLOCK_SIZE_BYTES])
bsize = nla_get_u64(info->attrs[NBD_ATTR_BLOCK_SIZE_BYTES]);
- if (!bsize)
- bsize = NBD_DEF_BLKSIZE;
- if (!nbd_is_valid_blksize(bsize)) {
- printk(KERN_ERR "Invalid block size %llu\n", bsize);
- return -EINVAL;
- }
- }

if (bytes != config->bytesize || bsize != config->blksize)
- nbd_set_size(nbd, bytes, bsize);
+ return nbd_set_size(nbd, bytes, bsize);
return 0;