[PATCH 10/24] nbd: validate the block size in nbd_set_size

[Christoph Hellwig <hch@xxxxxx>]

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

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
 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 eb8a5da48ad75a..327060e01ad58e 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;
@@ -1808,18 +1798,11 @@ 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;
 }
 
-- 
2.28.0