[PATCH -next] nvmet: fix return value check in nvmet_subsys_alloc()

[weiyj_lk]

From: Wei Yongjun <yongjun_...@trendmicro.com.cn>

In case of error, the function kstrndup() returns NULL pointer
not ERR_PTR(). The IS_ERR() test in the return value check
should be replaced with NULL test.

Signed-off-by: Wei Yongjun <yongjun_...@trendmicro.com.cn>
---
 drivers/nvme/target/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index e0b3f01..8a891ca 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -895,7 +895,7 @@ struct nvmet_subsys *nvmet_subsys_alloc(const char 
*subsysnqn,
        subsys->type = type;
        subsys->subsysnqn = kstrndup(subsysnqn, NVMF_NQN_SIZE,
                        GFP_KERNEL);
-       if (IS_ERR(subsys->subsysnqn)) {
+       if (!subsys->subsysnqn) {
                kfree(subsys);
                return NULL;
        }