Smatch complains that "rc_proto" comes from the user and it can result
in shift wrapping in ir_raw_encode_scancode()
drivers/media/rc/rc-ir-raw.c:526 ir_raw_encode_scancode()
error: undefined (user controlled) shift '1 << protocol'
This is true, but I reviewed the surrounding code and it appears
harmless. Anyway, let's verify that "rc_proto" is valid as a kernel
hardenning measure.
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
drivers/media/rc/lirc_dev.c | 3 ++-
include/uapi/linux/lirc.h | 1 +
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/include/uapi/linux/lirc.h b/include/uapi/linux/lirc.h
index f99d9dcae667..c1eb960adde3 100644
--- a/include/uapi/linux/lirc.h
+++ b/include/uapi/linux/lirc.h
@@ -226,6 +226,7 @@ enum rc_proto {
RC_PROTO_RCMM24 = 25,
RC_PROTO_RCMM32 = 26,
RC_PROTO_XBOX_DVD = 27,
+ RC_PROTO_MAX = RC_PROTO_XBOX_DVD,
};
#endif
diff --git a/drivers/media/rc/lirc_dev.c b/drivers/media/rc/lirc_dev.c
index 220363b9a868..116daf90c858 100644
--- a/drivers/media/rc/lirc_dev.c
+++ b/drivers/media/rc/lirc_dev.c
@@ -263,7 +263,8 @@ static ssize_t lirc_transmit(struct file *file, const char __user *buf,
goto out_unlock;
}
- if (scan.flags || scan.keycode || scan.timestamp) {
+ if (scan.flags || scan.keycode || scan.timestamp ||
+ scan.rc_proto > RC_PROTO_MAX) {
ret = -EINVAL;
goto out_unlock;
}
--
2.28.0
