Commit 6be88d5a authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Xponential31
Browse files

s390: ctcm: fix ctcm_new_device error return code 



[ Upstream commit 27b141fc234a3670d21bd742c35d7205d03cbb3a ]

clang points out that the return code from this function is
undefined for one of the error paths:

../drivers/s390/net/ctcm_main.c:1595:7: warning: variable 'result' is used uninitialized whenever 'if' condition is true
      [-Wsometimes-uninitialized]
                if (priv->channel[direction] == NULL) {
                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../drivers/s390/net/ctcm_main.c:1638:9: note: uninitialized use occurs here
        return result;
               ^~~~~~
../drivers/s390/net/ctcm_main.c:1595:3: note: remove the 'if' if its condition is always false
                if (priv->channel[direction] == NULL) {
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../drivers/s390/net/ctcm_main.c:1539:12: note: initialize the variable 'result' to silence this warning
        int result;
                  ^

Make it return -ENODEV here, as in the related failure cases.
gcc has a known bug in underreporting some of these warnings
when it has already eliminated the assignment of the return code
based on some earlier optimization step.

Reviewed-by: default avatarNathan Chancellor <natechancellor@gmail.com>
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
parent 266b4eff

drivers/s390/net/ctcm_main.c

+1 −0
Original line number Diff line number Diff line
@@ -1595,6 +1595,7 @@ static int ctcm_new_device(struct ccwgroup_device *cgdev) 
		if (priv->channel[direction] == NULL) {

			if (direction == CTCM_WRITE)

				channel_free(priv->channel[CTCM_READ]);

			result = -ENODEV;

			goto out_dev;

		}

		priv->channel[direction]->netdev = dev;