rapidio/tsi721: fix incorrect detection of address translation condition

Fix incorrect condition to identify involvment of a address translation
mechanism.

This bug results in NULL pointer kernel crash dump in cases when mapping
of inbound RapidIO address range is requested within existing aprture.

Link: http://lkml.kernel.org/r/20160901173144.2983-1-alexandre.bounine@idt.com
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com>
Cc: Barry Wood <barry.wood@idt.com>
Cc: <stable@vger.kernel.org>	[4.6+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/rapidio/devices/tsi721.c b/drivers/rapidio/devices/tsi721.c
index 32f0f01..9d19b9a 100644 (file)
--- a/drivers/rapidio/devices/tsi721.c
+++ b/drivers/rapidio/devices/tsi721.c
@@ -1161,7 +1161,7 @@ static int tsi721_rio_map_inb_mem(struct rio_mport *mport, dma_addr_t lstart,
                } else if (ibw_start < (ib_win->rstart + ib_win->size) &&
                           (ibw_start + ibw_size) > ib_win->rstart) {
                        /* Return error if address translation involved */
-                       if (direct && ib_win->xlat) {
+                       if (!direct || ib_win->xlat) {
                                ret = -EFAULT;
                                break;
                        }