File hw-sd-sdhci-Fix-DMA-Transfer-Block-Size-.patch of Package qemu.21548

Overview Repositories Revisions Requests Users Attributes Meta

File hw-sd-sdhci-Fix-DMA-Transfer-Block-Size-.patch of Package qemu.21548

From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= <f4bug@amsat.org>
Date: Tue, 1 Sep 2020 15:22:06 +0200
Subject: hw/sd/sdhci: Fix DMA Transfer Block Size field
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Git-commit: dfba99f17feb6d4a129da19d38df1bcd8579d1c3
References: bsc#1176681 CVE-2020-25085

The 'Transfer Block Size' field is 12-bit wide.

See section '2.2.2. Block Size Register (Offset 004h)' in datasheet.

Two different bug reproducer available:
- https://bugs.launchpad.net/qemu/+bug/1892960
- https://ruhr-uni-bochum.sciebo.de/s/NNWP2GfwzYKeKwE?path=%2Fsdhci_oob_write1

Cc: qemu-stable@nongnu.org
Buglink: https://bugs.launchpad.net/qemu/+bug/1892960
Fixes: d7dfca0807a ("hw/sdhci: introduce standard SD host controller")
Reported-by: Alexander Bulekov <alxndr@bu.edu>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Prasad J Pandit <pjp@fedoraproject.org>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20200901140411.112150-3-f4bug@amsat.org>
Signed-off-by: Jose R Ziviani <jose.ziviani@suse.com>
---
 hw/sd/sdhci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
index 88404d0e9d5a0acafceec1933fce..c27bd0936505c9ae75aec7ab24d2 100644
--- a/hw/sd/sdhci.c
+++ b/hw/sd/sdhci.c
@@ -1129,7 +1129,7 @@ sdhci_write(void *opaque, hwaddr offset, uint64_t val, unsigned size)
         break;
     case SDHC_BLKSIZE:
         if (!TRANSFERRING_DATA(s->prnsts)) {
-            MASKED_WRITE(s->blksize, mask, value);
+            MASKED_WRITE(s->blksize, mask, extract32(value, 0, 12));
             MASKED_WRITE(s->blkcnt, mask >> 16, value >> 16);
         }

Places

File hw-sd-sdhci-Fix-DMA-Transfer-Block-Size-.patch of Package qemu.21548

Places