mmc: at91_mci: fix pointer errors

Fixes two pointer errors, one which leads to memory overwrites if used with large chunks of data. Signed-off-by: Wolfgang Muees <[email protected]> Signed-off-by: Nicolas Ferre <[email protected]> Cc: Andrew Victor <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
josf · Mar 6, 2010 · 0b3520f · 0b3520f
1 parent dc2ed55
commit 0b3520f
Showing 1 changed file with 5 additions and 3 deletions.
diff --git a/drivers/mmc/host/at91_mci.c b/drivers/mmc/host/at91_mci.c
@@ -227,11 +227,13 @@ static inline void at91_mci_sg_to_dma(struct at91mci_host *host, struct mmc_data
 			for (index = 0; index < (amount / 4); index++)
 				*dmabuf++ = swab32(sgbuffer[index]);
 		} else {
-			memcpy(dmabuf, sgbuffer, amount);
-			dmabuf += amount;
+			char *tmpv = (char *)dmabuf;
+			memcpy(tmpv, sgbuffer, amount);
+			tmpv += amount;
+			dmabuf = (unsigned *)tmpv;
 		}
 
-		kunmap_atomic(sgbuffer, KM_BIO_SRC_IRQ);
+		kunmap_atomic(((void *)sgbuffer) - sg->offset, KM_BIO_SRC_IRQ);
 
 		if (size == 0)
 			break;