RDMA/ucma: Correct option size check using optlen

BugLink: https://bugs.launchpad.net/bugs/1775771

[ Upstream commit 5f3e3b85 ]

The option size check is using optval instead of optlen
causing the set option call to fail. Use the correct
field, optlen, for size check.

Fixes: 6a21dfc0 ("RDMA/ucma: Limit possible option size")
Signed-off-by: Chien Tin Tung <chien.tin.tung@intel.com>
Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

drivers/infiniband/core/ucma.c

@@ -1295,7 +1295,7 @@ static ssize_t ucma_set_option(struct ucma_file *file, const char __user *inbuf,
 	if (IS_ERR(ctx))
 		return PTR_ERR(ctx);
 
-	if (unlikely(cmd.optval > KMALLOC_MAX_SIZE))
+	if (unlikely(cmd.optlen > KMALLOC_MAX_SIZE))
 		return -EINVAL;
 
 	optval = memdup_user((void __user *) (unsigned long) cmd.optval,