[PATCH v2 1/6] hw/sd: sdhci: Don't transfer any data when command time out

[Bin Meng <bmeng.cn@gmail.com>]

At the end of sdhci_send_command(), it starts a data transfer if the
command register indicates data is associated. But the data transfer
should only be initiated when the command execution has succeeded.

With this fix, the following reproducer:

outl 0xcf8 0x80001810
outl 0xcfc 0xe1068000
outl 0xcf8 0x80001804
outw 0xcfc 0x7
write 0xe106802c 0x1 0x0f
write 0xe1068004 0xc 0x2801d10101fffffbff28a384
write 0xe106800c 0x1f 0x9dacbbcad9e8f7061524334251606f7e8d9cabbac9d8e7f60514233241505f
write 0xe1068003 0x28 0x80d000251480d000252280d000253080d000253e80d000254c80d000255a80d000256880d0002576
write 0xe1068003 0x1 0xfe

cannot be reproduced with the following QEMU command line:

$ qemu-system-x86_64 -nographic -M pc-q35-5.0 \
      -device sdhci-pci,sd-spec-version=3 \
      -drive if=sd,index=0,file=null-co://,format=raw,id=mydrive \
      -device sd-card,drive=mydrive \
      -monitor none -serial none -qtest stdio

Cc: qemu-stable@nongnu.org
Fixes: CVE-2020-17380
Fixes: CVE-2020-25085
Fixes: CVE-2021-3409
Fixes: d7dfca0807a0 ("hw/sdhci: introduce standard SD host controller")
Reported-by: Alexander Bulekov <alxndr@bu.edu>
Reported-by: Cornelius Aschermann (Ruhr-University Bochum)
Reported-by: Muhammad Ramdhan
Reported-by: Sergej Schumilo (Ruhr-University Bochum)
Reported-by: Simon Wrner (Ruhr-University Bochum)
Buglink: https://bugs.launchpad.net/qemu/+bug/1892960
Buglink: https://bugs.launchpad.net/qemu/+bug/1909418
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1928146
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---

(no changes since v1)

 hw/sd/sdhci.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
index 8ffa539..1c5ab26 100644
--- a/hw/sd/sdhci.c
+++ b/hw/sd/sdhci.c
@@ -326,6 +326,7 @@ static void sdhci_send_command(SDHCIState *s)
     SDRequest request;
     uint8_t response[16];
     int rlen;
+    bool timeout = false;
 
     s->errintsts = 0;
     s->acmd12errsts = 0;
@@ -349,6 +350,7 @@ static void sdhci_send_command(SDHCIState *s)
             trace_sdhci_response16(s->rspreg[3], s->rspreg[2],
                                    s->rspreg[1], s->rspreg[0]);
         } else {
+            timeout = true;
             trace_sdhci_error("timeout waiting for command response");
             if (s->errintstsen & SDHC_EISEN_CMDTIMEOUT) {
                 s->errintsts |= SDHC_EIS_CMDTIMEOUT;
@@ -369,7 +371,7 @@ static void sdhci_send_command(SDHCIState *s)
 
     sdhci_update_irq(s);
 
-    if (s->blksize && (s->cmdreg & SDHC_CMD_DATA_PRESENT)) {
+    if (!timeout && s->blksize && (s->cmdreg & SDHC_CMD_DATA_PRESENT)) {
         s->data_count = 0;
         sdhci_data_transfer(s);
     }
-- 
2.7.4