RDMA/uverbs: Check for null return of kmalloc_array

[PATCH] RDMA/uverbs: Check for null return of kmalloc_array

Posted by Jiasheng Jiang 4 years, 6 months ago

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")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
 drivers/infiniband/core/uverbs_uapi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/infiniband/core/uverbs_uapi.c b/drivers/infiniband/core/uverbs_uapi.c
index 62f5bcb712cf..1e71925613cc 100644
--- a/drivers/infiniband/core/uverbs_uapi.c
+++ b/drivers/infiniband/core/uverbs_uapi.c
@@ -447,6 +447,9 @@ 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;
-- 
2.25.1

Re: [PATCH] RDMA/uverbs: Check for null return of kmalloc_array

Posted by Leon Romanovsky 4 years, 5 months ago

On Fri, Dec 31, 2021 at 05:33:15PM +0800, Jiasheng Jiang wrote:
> 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")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> ---
>  drivers/infiniband/core/uverbs_uapi.c | 3 +++
>  1 file changed, 3 insertions(+)
> 

Thanks,
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>

Re: [PATCH] RDMA/uverbs: Check for null return of kmalloc_array

Posted by Jason Gunthorpe 4 years, 5 months ago

On Fri, Dec 31, 2021 at 05:33:15PM +0800, Jiasheng Jiang wrote:
> 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")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
> ---
>  drivers/infiniband/core/uverbs_uapi.c | 3 +++
>  1 file changed, 3 insertions(+)

Applied to for-rc, thanks

Jason