ieee802154/adf7242: check status of adf7242_read_reg

[ Upstream commit e3914ed6cf44bfe1f169e26241f8314556fd1ac1 ]

Clang static analysis reports this error

adf7242.c:887:6: warning: Assigned value is garbage or undefined
        len = len_u8;
            ^ ~~~~~~

len_u8 is set in
       adf7242_read_reg(lp, 0, &len_u8);

When this call fails, len_u8 is not set.

So check the return code.

Fixes: 7302b9d90117 ("ieee802154/adf7242: Driver for ADF7242 MAC IEEE802154")
Signed-off-by: Tom Rix <trix@redhat.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Link: https://lore.kernel.org/r/20200802142339.21091-1-trix@redhat.com
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ieee802154/adf7242.c b/drivers/net/ieee802154/adf7242.c
index 1b980f12663afc259da33422b6c4abb6057ab4ec..a605dfb15bb75d153d45dd3212dcfd7f0dd876b2 100644 (file)
--- a/drivers/net/ieee802154/adf7242.c
+++ b/drivers/net/ieee802154/adf7242.c
@@ -834,7 +834,9 @@ static int adf7242_rx(struct adf7242_local *lp)
        int ret;
        u8 lqi, len_u8, *data;
 
-       adf7242_read_reg(lp, 0, &len_u8);
+       ret = adf7242_read_reg(lp, 0, &len_u8);
+       if (ret)
+               return ret;
 
        len = len_u8;