Per "SD Host Controller Standard Specification Version 7.00"
chapter 2.2.1 SDMA System Address Register:
This register can be accessed only if no transaction is executing
(i.e., after a transaction has stopped).
With this fix, the following reproducer:
https://paste.debian.net/plain/1185137
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 | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)
diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
index 1c5ab26..05cb281 100644
--- a/hw/sd/sdhci.c
+++ b/hw/sd/sdhci.c
@@ -1122,15 +1122,17 @@ sdhci_write(void *opaque, hwaddr offset, uint64_t val, unsigned size)
switch (offset & ~0x3) {
case SDHC_SYSAD:
- s->sdmasysad = (s->sdmasysad & mask) | value;
- MASKED_WRITE(s->sdmasysad, mask, value);
- /* Writing to last byte of sdmasysad might trigger transfer */
- if (!(mask & 0xFF000000) && TRANSFERRING_DATA(s->prnsts) && s->blkcnt &&
- s->blksize && SDHC_DMA_TYPE(s->hostctl1) == SDHC_CTRL_SDMA) {
- if (s->trnmod & SDHC_TRNS_MULTI) {
- sdhci_sdma_transfer_multi_blocks(s);
- } else {
- sdhci_sdma_transfer_single_block(s);
+ if (!TRANSFERRING_DATA(s->prnsts)) {
+ s->sdmasysad = (s->sdmasysad & mask) | value;
+ MASKED_WRITE(s->sdmasysad, mask, value);
+ /* Writing to last byte of sdmasysad might trigger transfer */
+ if (!(mask & 0xFF000000) && s->blkcnt && s->blksize &&
+ SDHC_DMA_TYPE(s->hostctl1) == SDHC_CTRL_SDMA) {
+ if (s->trnmod & SDHC_TRNS_MULTI) {
+ sdhci_sdma_transfer_multi_blocks(s);
+ } else {
+ sdhci_sdma_transfer_single_block(s);
+ }
}
}
break;
--
2.7.4
On 2/16/21 4:46 AM, Bin Meng wrote:
> Per "SD Host Controller Standard Specification Version 7.00"
> chapter 2.2.1 SDMA System Address Register:
>
> This register can be accessed only if no transaction is executing
> (i.e., after a transaction has stopped).
>
> With this fix, the following reproducer:
>
> https://paste.debian.net/plain/1185137
The reproducer is not huge, so better bury it with the commit
description:
outl 0xcf8 0x80001010
outl 0xcfc 0xfbefff00
outl 0xcf8 0x80001001
outl 0xcfc 0x06000000
write 0xfbefff2c 0x1 0x05
write 0xfbefff0f 0x1 0x37
write 0xfbefff0a 0x1 0x01
write 0xfbefff0f 0x1 0x29
write 0xfbefff0f 0x1 0x02
write 0xfbefff0f 0x1 0x03
write 0xfbefff04 0x1 0x01
write 0xfbefff05 0x1 0x01
write 0xfbefff07 0x1 0x02
write 0xfbefff0c 0x1 0x33
write 0xfbefff0e 0x1 0x20
write 0xfbefff0f 0x1 0x00
write 0xfbefff2a 0x1 0x01
write 0xfbefff0c 0x1 0x00
write 0xfbefff03 0x1 0x00
write 0xfbefff05 0x1 0x00
write 0xfbefff2a 0x1 0x02
write 0xfbefff0c 0x1 0x32
write 0xfbefff01 0x1 0x01
write 0xfbefff02 0x1 0x01
write 0xfbefff03 0x1 0x01
> 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
and even better add as qtest in tests/qtest/fuzz-sdhci-test.c :)
> 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 | 20 +++++++++++---------
> 1 file changed, 11 insertions(+), 9 deletions(-)
>
> diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
> index 1c5ab26..05cb281 100644
> --- a/hw/sd/sdhci.c
> +++ b/hw/sd/sdhci.c
> @@ -1122,15 +1122,17 @@ sdhci_write(void *opaque, hwaddr offset, uint64_t val, unsigned size)
>
> switch (offset & ~0x3) {
> case SDHC_SYSAD:
> - s->sdmasysad = (s->sdmasysad & mask) | value;
> - MASKED_WRITE(s->sdmasysad, mask, value);
> - /* Writing to last byte of sdmasysad might trigger transfer */
> - if (!(mask & 0xFF000000) && TRANSFERRING_DATA(s->prnsts) && s->blkcnt &&
> - s->blksize && SDHC_DMA_TYPE(s->hostctl1) == SDHC_CTRL_SDMA) {
> - if (s->trnmod & SDHC_TRNS_MULTI) {
> - sdhci_sdma_transfer_multi_blocks(s);
> - } else {
> - sdhci_sdma_transfer_single_block(s);
> + if (!TRANSFERRING_DATA(s->prnsts)) {
> + s->sdmasysad = (s->sdmasysad & mask) | value;
> + MASKED_WRITE(s->sdmasysad, mask, value);
> + /* Writing to last byte of sdmasysad might trigger transfer */
> + if (!(mask & 0xFF000000) && s->blkcnt && s->blksize &&
> + SDHC_DMA_TYPE(s->hostctl1) == SDHC_CTRL_SDMA) {
> + if (s->trnmod & SDHC_TRNS_MULTI) {
> + sdhci_sdma_transfer_multi_blocks(s);
> + } else {
> + sdhci_sdma_transfer_single_block(s);
> + }
Can you add:
} else {
qemu_log_mask(LOG_GUEST_ERROR,
"%s: Transfer already in progress, can not update
SYSAD",
__func__);
> }
> }
> break;
>
On 2/16/21 4:46 AM, Bin Meng wrote: > Per "SD Host Controller Standard Specification Version 7.00" > chapter 2.2.1 SDMA System Address Register: > > This register can be accessed only if no transaction is executing > (i.e., after a transaction has stopped). > > With this fix, the following reproducer: > > https://paste.debian.net/plain/1185137 > > 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 Without the rest applied, I still can :( AddressSanitizer: heap-buffer-overflow
On 2/18/21 7:23 PM, Philippe Mathieu-Daudé wrote: > On 2/16/21 4:46 AM, Bin Meng wrote: >> Per "SD Host Controller Standard Specification Version 7.00" >> chapter 2.2.1 SDMA System Address Register: >> >> This register can be accessed only if no transaction is executing >> (i.e., after a transaction has stopped). >> >> With this fix, the following reproducer: >> >> https://paste.debian.net/plain/1185137 >> >> 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 > > Without the rest applied, I still can :( > > AddressSanitizer: heap-buffer-overflow Err, I used an old build for this test, sorry...
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