On Fri, Jul 08, 2022 at 10:19:47AM +0100, Srinivas Kandagatla wrote:
Controller only supports up to max of 1-11 device ids via auto-enumeration, and it has only those many registers.
In the existing code, we can protentially cross this boundary and read incorrect registers.
Cc: stable@vger.kernel.org Reported-by: Dan Carpenter dan.carpenter@oracle.com Fixes: a6e6581942ca ("soundwire: qcom: add auto enumeration support") Signed-off-by: Srinivas Kandagatla srinivas.kandagatla@linaro.org
Thanks to Dan for reporting an overflow issue, which turned out to be another issue, where we could read registers that do not belong to auto-enumeration devid. Either way this fixes both issues, one reported by Dan and other incorrect register access.
Thanks, Srini
drivers/soundwire/qcom.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c index 9df970eeca45..dd1365a44458 100644 --- a/drivers/soundwire/qcom.c +++ b/drivers/soundwire/qcom.c @@ -119,6 +119,8 @@ #define MAX_FIFO_RD_RETRY 3 #define SWR_OVERFLOW_RETRY_COUNT 30 #define SWRM_LINK_STATUS_RETRY_CNT 100 +/* devid 1 - 11 */ +#define SWRM_MAX_AUTO_ENUM_DEVICES 11 enum { MASTER_ID_WSA = 1, @@ -479,7 +481,7 @@ static int qcom_swrm_enumerate(struct sdw_bus *bus) int i; char *buf1 = (char *)&val1, *buf2 = (char *)&val2;
- for (i = 1; i <= SDW_MAX_DEVICES; i++) {
- for (i = 1; i <= SWRM_MAX_AUTO_ENUM_DEVICES; i++) {
I'm sorry, I don't understand. Both of these defines are 11 so this doesn't change anything?
regards, dan carpenter
/* do not continue if the status is Not Present */ if (!ctrl->status[i]) continue;-- 2.25.1