[patch] RDMA/uverbs: potential integer overflow

[patch] RDMA/uverbs: potential integer overflow

[Dan Carpenter]

This is a static checker fix, and I'm not super familiar with this code.

My checker complains that user_wr->num_sge + sg_ind can have an integer
overflow and wrap.  That's is true, but I don't know the code well
enough to say if it's a problem or not.

Can someone take a look at this?

Signed-off-by: Dan Carpenter <dan.carpenter-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>

diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 254f164..e57b6d7 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -1939,7 +1939,8 @@ ssize_t ib_uverbs_post_send(struct ib_uverbs_file *file,
 			goto out_put;
 		}
 
-		if (user_wr->num_sge + sg_ind > cmd.sge_count) {
+		if (user_wr->num_sge > cmd.sge_count ||
+				user_wr->num_sge + sg_ind > cmd.sge_count) {
 			ret = -EINVAL;
 			goto out_put;
 		}
@@ -2085,7 +2086,8 @@ static struct ib_recv_wr *ib_uverbs_unmarshall_recv(const char __user *buf,
 			goto err;
 		}
 
-		if (user_wr->num_sge + sg_ind > sge_count) {
+		if (user_wr->num_sge > sge_count ||
+				user_wr->num_sge + sg_ind > sge_count) {
 			ret = -EINVAL;
 			goto err;
 		}
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Re: [patch] RDMA/uverbs: potential integer overflow

[Dan Carpenter]

I was looking through old integer overflows, and I was still wondering
if this is buggy.

regards,
dan carpenter

On 12/1/11, Dan Carpenter <dan.carpenter-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org> wrote:
> This is a static checker fix, and I'm not super familiar with this code.
>
> My checker complains that user_wr->num_sge + sg_ind can have an integer
> overflow and wrap.  That's is true, but I don't know the code well
> enough to say if it's a problem or not.
>
> Can someone take a look at this?
>
> Signed-off-by: Dan Carpenter <dan.carpenter-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
>
> diff --git a/drivers/infiniband/core/uverbs_cmd.c
> b/drivers/infiniband/core/uverbs_cmd.c
> index 254f164..e57b6d7 100644
> --- a/drivers/infiniband/core/uverbs_cmd.c
> +++ b/drivers/infiniband/core/uverbs_cmd.c
> @@ -1939,7 +1939,8 @@ ssize_t ib_uverbs_post_send(struct ib_uverbs_file
> *file,
>  			goto out_put;
>  		}
>
> -		if (user_wr->num_sge + sg_ind > cmd.sge_count) {
> +		if (user_wr->num_sge > cmd.sge_count ||
> +				user_wr->num_sge + sg_ind > cmd.sge_count) {
>  			ret = -EINVAL;
>  			goto out_put;
>  		}
> @@ -2085,7 +2086,8 @@ static struct ib_recv_wr
> *ib_uverbs_unmarshall_recv(const char __user *buf,
>  			goto err;
>  		}
>
> -		if (user_wr->num_sge + sg_ind > sge_count) {
> +		if (user_wr->num_sge > sge_count ||
> +				user_wr->num_sge + sg_ind > sge_count) {
>  			ret = -EINVAL;
>  			goto err;
>  		}
> --
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