From: Michael Olbrich <m.olbrich@pengutronix.de>
Date: Fri, 6 Oct 2017 15:46:47 +0000 (+0100)
Subject: hw/sd: fix out-of-bounds check for multi block reads
X-Git-Tag: v2.10.2~32
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=64f62e4e901e268696234e13357d7b978ad29f1e;p=thirdparty%2Fqemu.git

hw/sd: fix out-of-bounds check for multi block reads

The current code checks if the next block exceeds the size of the card.
This generates an error while reading the last block of the card.
Do the out-of-bounds check when starting to read a new block to fix this.

This issue became visible with increased error checking in Linux 4.13.

Cc: qemu-stable@nongnu.org
Signed-off-by: Michael Olbrich <m.olbrich@pengutronix.de>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Message-id: 20170916091611.10241-1-m.olbrich@pengutronix.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
(cherry picked from commit 8573378e62d19e25a2434e23462ec99ef4d065ac)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---

diff --git a/hw/sd/sd.c b/hw/sd/sd.c
index ba47bff4db8..35347a5bbcd 100644
--- a/hw/sd/sd.c
+++ b/hw/sd/sd.c
@@ -1797,8 +1797,13 @@ uint8_t sd_read_data(SDState *sd)
         break;
 
     case 18:	/* CMD18:  READ_MULTIPLE_BLOCK */
-        if (sd->data_offset == 0)
+        if (sd->data_offset == 0) {
+            if (sd->data_start + io_len > sd->size) {
+                sd->card_status |= ADDRESS_ERROR;
+                return 0x00;
+            }
             BLK_READ_BLOCK(sd->data_start, io_len);
+        }
         ret = sd->data[sd->data_offset ++];
 
         if (sd->data_offset >= io_len) {
@@ -1812,11 +1817,6 @@ uint8_t sd_read_data(SDState *sd)
                     break;
                 }
             }
-
-            if (sd->data_start + io_len > sd->size) {
-                sd->card_status |= ADDRESS_ERROR;
-                break;
-            }
         }
         break;