drivers/rapidio/devices/rio_mport_cdev.c: fix resource leak in error …

…handling path in 'rio_dma_transfer()'

If 'dma_map_sg()', we should branch to the existing error handling path
to free some resources before returning.

Link: http://lkml.kernel.org/r/61292a4f369229eee03394247385e955027283f8.1505687047.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Christian K_nig <christian.koenig@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rapidio/devices/rio_mport_cdev.c

@@ -963,7 +963,8 @@ rio_dma_transfer(struct file *filp, u32 transfer_mode,
 			   req->sgt.sgl, req->sgt.nents, dir);
 	if (nents == -EFAULT) {
 		rmcd_error("Failed to map SG list");
-		return -EFAULT;
+		ret = -EFAULT;
+		goto err_pg;
 	}
 
 	ret = do_dma_request(req, xfer, sync, nents);