From 8ca0e780b4e88e90f933a4f4b52f82bb6d303416 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Tue, 5 May 2020 10:25:56 +0200 Subject: [PATCH] media: cec: silence shift wrapping warning in __cec_s_log_addrs() [ Upstream commit 3b5af3171e2d5a73ae6f04965ed653d039904eb6 ] 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: 9881fe0ca187 ("[media] cec: add HDMI CEC framework (adapter)") Signed-off-by: Dan Carpenter Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/cec/cec-adap.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/media/cec/cec-adap.c b/drivers/media/cec/cec-adap.c index b14c09cd9593..06383b26712b 100644 --- a/drivers/media/cec/cec-adap.c +++ b/drivers/media/cec/cec-adap.c @@ -1732,6 +1732,10 @@ 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; @@ -1752,10 +1756,6 @@ 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)