On Thu, Feb 03, 2022 at 09:14:47PM +0300, Dan Carpenter wrote:
> From: Haimin Zhang <tcs.kernel@xxxxxxxxx>
>
> The ib_copy_ah_attr_to_user() function only initializes "resp.grh" if
> the "resp.is_global" flag is set. Unfortunately, this data is copied to
> the user and copying uninitialized stack data to the user is an
> information leak. Zero out the whole struct to be safe.
>
> Fixes: 4ba66093bdc6 ("IB/core: Check for global flag when using ah_attr")
> Reported-by: TCS Robot <tcs_robot@xxxxxxxxxxx>
> Signed-off-by: Haimin Zhang <tcs.kernel@xxxxxxxxx>
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> ---
> Resending through the regular lists.
>
> I added parentheses around the sizeof to make checkpatch happy.
> s/sizeof resp/sizeof(resp)/.
>
> drivers/infiniband/core/ucma.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
The change is ok, but I prefer to initialize to zero as early as possible.
diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c
index 2b72c4fa9550..6d801ed2e46b 100644
--- a/drivers/infiniband/core/ucma.c
+++ b/drivers/infiniband/core/ucma.c
@@ -1211,9 +1211,9 @@ static ssize_t ucma_init_qp_attr(struct ucma_file *file,
int in_len, int out_len)
{
struct rdma_ucm_init_qp_attr cmd;
- struct ib_uverbs_qp_attr resp;
+ struct ib_uverbs_qp_attr resp = {};
struct ucma_context *ctx;
- struct ib_qp_attr qp_attr;
+ struct ib_qp_attr qp_attr = {};
int ret;
if (out_len < sizeof(resp))
@@ -1229,8 +1229,6 @@ static ssize_t ucma_init_qp_attr(struct ucma_file *file,
if (IS_ERR(ctx))
return PTR_ERR(ctx);
- resp.qp_attr_mask = 0;
- memset(&qp_attr, 0, sizeof qp_attr);
qp_attr.qp_state = cmd.qp_state;
mutex_lock(&ctx->mutex);
ret = rdma_init_qp_attr(ctx->cm_id, &qp_attr, &resp.qp_attr_mask);
>
> diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c
> index 9d6ac9dff39a..91485f13d842 100644
> --- a/drivers/infiniband/core/ucma.c
> +++ b/drivers/infiniband/core/ucma.c
> @@ -1232,7 +1232,7 @@ static ssize_t ucma_init_qp_attr(struct ucma_file *file,
> if (IS_ERR(ctx))
> return PTR_ERR(ctx);
>
> - resp.qp_attr_mask = 0;
> + memset(&resp, 0, sizeof(resp));
> memset(&qp_attr, 0, sizeof qp_attr);
> qp_attr.qp_state = cmd.qp_state;
> mutex_lock(&ctx->mutex);
> --
> 2.20.1
>
