Re: [PATCH v2 3/6] hw/sd: sdhci: Correctly set the controller status for ADMA

[Philippe Mathieu-Daudé]

On 2/16/21 4:46 AM, Bin Meng wrote:
> When an ADMA transfer is started, the codes forget to set the
> controller status to indicate a transfer is in progress.
> 
> With this fix, the following 2 reproducers:
> 
> https://paste.debian.net/plain/1185136
> https://paste.debian.net/plain/1185141
> 
> cannot be reproduced with the following QEMU command line:
> 
> $ qemu-system-x86_64 -nographic -machine accel=qtest -m 512M \
>       -nodefaults -device sdhci-pci,sd-spec-version=3 \
>       -drive if=sd,index=0,file=null-co://,format=raw,id=mydrive \
>       -device sd-card,drive=mydrive -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>
> ---
> 
> (no changes since v1)
> 
>  hw/sd/sdhci.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
> index 05cb281..0b0ca6f 100644
> --- a/hw/sd/sdhci.c
> +++ b/hw/sd/sdhci.c
> @@ -769,7 +769,9 @@ static void sdhci_do_adma(SDHCIState *s)
>  
>          switch (dscr.attr & SDHC_ADMA_ATTR_ACT_MASK) {
>          case SDHC_ADMA_ATTR_ACT_TRAN:  /* data transfer */
> +            s->prnsts |= SDHC_DATA_INHIBIT | SDHC_DAT_LINE_ACTIVE;
>              if (s->trnmod & SDHC_TRNS_READ) {
> +                s->prnsts |= SDHC_DOING_READ;
>                  while (length) {
>                      if (s->data_count == 0) {
>                          sdbus_read_data(&s->sdbus, s->fifo_buffer, 
> block_size);
> @@ -797,6 +799,7 @@ static void sdhci_do_adma(SDHCIState *s)
>                      }
>                  }
>              } else {
> +                s->prnsts |= SDHC_DOING_WRITE;
>                  while (length) {
>                      begin = s->data_count;
>                      if ((length + begin) < block_size) {

Nice fix.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>