Only move the state machine to ReceivingData if there is no
pending error. This avoids later OOB access while processing
commands queued.
"SD Specifications Part 1 Physical Layer Simplified Spec. v3.01"
4.3.3 Data Read
Read command is rejected if BLOCK_LEN_ERROR or ADDRESS_ERROR
occurred and no data transfer is performed.
4.3.4 Data Write
Write command is rejected if BLOCK_LEN_ERROR or ADDRESS_ERROR
occurred and no data transfer is performed.
WP_VIOLATION errors are not modified: the error bit is set, we
stay in receive-data state, wait for a stop command. All further
data transfer is ignored. See the check on sd->card_status at the
beginning of sd_read_data() and sd_write_data().
Fixes: CVE-2020-13253
Cc: qemu-stable@nongnu.org
Reported-by: Alexander Bulekov <alxndr@bu.edu>
Buglink: https://bugs.launchpad.net/qemu/+bug/1880822
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20200630133912.9428-6-f4bug@amsat.org>
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