mmc: atmel-mci: fix oops in atmci_tasklet_func

In some cases, a NULL pointer dereference happens because data is NULL when
STATE_END_REQUEST case is reached in atmci_tasklet_func.

Cc: <stable@vger.kernel.org> # 3.9+
Signed-off-by: Rodolfo Giometti <giometti@enneenne.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 8 insertions, 6 deletions

diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index b8dfe0d8adbb..92c18779d47e 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -1810,12 +1810,14 @@ static void atmci_tasklet_func(unsigned long priv)
                         if (unlikely(status)) {
                                 host->stop_transfer(host);
                                 host->data = NULL;
-                                if (status & ATMCI_DTOE) {
-                                        data->error = -ETIMEDOUT;
-                                } else if (status & ATMCI_DCRCE) {
-                                        data->error = -EILSEQ;
-                                } else {
-                                        data->error = -EIO;
+                                if (data) {
+                                        if (status & ATMCI_DTOE) {
+                                                data->error = -ETIMEDOUT;
+                                        } else if (status & ATMCI_DCRCE) {
+                                                data->error = -EILSEQ;
+                                        } else {
+                                                data->error = -EIO;
+                                        }
                                 }
                         }