RDMA/uverbs: Check for null return of kmalloc_array

commit 7694a7de22c53a312ea98960fcafc6ec62046531 upstream.

Because of the possible failure of the allocation, data might be NULL
pointer and will cause the dereference of the NULL pointer later.
Therefore, it might be better to check it and return -ENOMEM.

Fixes: 6884c6c4bd09 ("RDMA/verbs: Store the write/write_ex uapi entry points in the uverbs_api")
Link: https://lore.kernel.org/r/20211231093315.1917667-1-jiasheng@iscas.ac.cn
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/infiniband/core/uverbs_uapi.c b/drivers/infiniband/core/uverbs_uapi.c
index 5addc8fae3f3bd9083d2e59fac0662f9f0296aeb..91dbcb3c252d67c8f8e6a8d4e2ddceffd26bfc9f 100644 (file)
--- a/drivers/infiniband/core/uverbs_uapi.c
+++ b/drivers/infiniband/core/uverbs_uapi.c
@@ -450,6 +450,9 @@ static int uapi_finalize(struct uverbs_api *uapi)
        uapi->num_write_ex = max_write_ex + 1;
        data = kmalloc_array(uapi->num_write + uapi->num_write_ex,
                             sizeof(*uapi->write_methods), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
        for (i = 0; i != uapi->num_write + uapi->num_write_ex; i++)
                data[i] = &uapi->notsupp_method;
        uapi->write_methods = data;