ide: add missing validity checks for identify words 62 and 63

Check validity of identify words 62 and 63 before using them in
ide_get_mode_mask().

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/ide/ide-dma.c b/drivers/ide/ide-dma.c
index de33e6f88f17..ada2a3ea9430 100644
--- a/drivers/ide/ide-dma.c
+++ b/drivers/ide/ide-dma.c
@@ -731,10 +731,12 @@ static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base)
                         mask &= 0x07;
                 break;
         case XFER_MW_DMA_0:
-                mask = id->dma_mword & hwif->mwdma_mask;
+                if (id->field_valid & 2)
+                        mask = id->dma_mword & hwif->mwdma_mask;
                 break;
         case XFER_SW_DMA_0:
-                mask = id->dma_1word & hwif->swdma_mask;
+                if (id->field_valid & 2)
+                        mask = id->dma_1word & hwif->swdma_mask;
                 break;
         default:
                 BUG();