Commit 3b5af317 authored by Dan Carpenter's avatar Dan Carpenter Committed by Mauro Carvalho Chehab
Browse files

media: cec: silence shift wrapping warning in __cec_s_log_addrs() 



The log_addrs->log_addr_type[i] value is a u8 which is controlled by
the user and comes from the ioctl.  If it's over 31 then that results in
undefined behavior (shift wrapping) and that leads to a Smatch static
checker warning.  We already cap the value later so we can silence the
warning just by re-ordering the existing checks.

I think the UBSan checker will also catch this bug at runtime and
generate a warning.  But otherwise the bug is harmless.

Fixes: 9881fe0c ("[media] cec: add HDMI CEC framework (adapter)")
Signed-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent 62eedb35

drivers/media/cec/core/cec-adap.c

+4 −4
Original line number Diff line number Diff line
@@ -1734,6 +1734,10 @@ int __cec_s_log_addrs(struct cec_adapter *adap, 
		unsigned j;



		log_addrs->log_addr[i] = CEC_LOG_ADDR_INVALID;

		if (log_addrs->log_addr_type[i] > CEC_LOG_ADDR_TYPE_UNREGISTERED) {

			dprintk(1, "unknown logical address type\n");

			return -EINVAL;

		}

		if (type_mask & (1 << log_addrs->log_addr_type[i])) {

			dprintk(1, "duplicate logical address type\n");

			return -EINVAL;
@@ -1754,10 +1758,6 @@ int __cec_s_log_addrs(struct cec_adapter *adap, 
			dprintk(1, "invalid primary device type\n");

			return -EINVAL;

		}

		if (log_addrs->log_addr_type[i] > CEC_LOG_ADDR_TYPE_UNREGISTERED) {

			dprintk(1, "unknown logical address type\n");

			return -EINVAL;

		}

		for (j = 0; j < feature_sz; j++) {

			if ((features[j] & 0x80) == 0) {

				if (op_is_dev_features)