[PATCH v3] net: mlx5: Add a missing check on idr_find, free buf

From: Aditya Pakki
Date: Tue Mar 19 2019 - 12:24:18 EST


idr_find() can return a NULL value to 'flow' which is used without a check.
The patch adds a check to avoid potential NULL pointer dereference.
In case of mlx5_fpga_sbu_conn_sendmsg() failure, free buf allocated
using kzalloc.

---
Fixes: ab412e1dd7db ('net/mlx5: Accel, add TLS rx offload routines')
v2: failure to return in case of flow failure.
v1: Failed to free buf in case of flow failure.

Signed-off-by: Aditya Pakki <pakki001@xxxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c b/drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c
index 5cf5f2a9d51f..224e0d7f6489 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c
@@ -226,6 +226,11 @@ int mlx5_fpga_tls_resync_rx(struct mlx5_core_dev *mdev, u32 handle, u32 seq,
rcu_read_lock();
flow = idr_find(&mdev->fpga->tls->rx_idr, ntohl(handle));
rcu_read_unlock();
+ if (!flow) {
+ WARN_ONCE(1, "Received NULL pointer for handle\n");
+ kfree(buf);
+ return -EINVAL;
+ }
mlx5_fpga_tls_flow_to_cmd(flow, cmd);

MLX5_SET(tls_cmd, cmd, swid, ntohl(handle));
@@ -238,6 +243,8 @@ int mlx5_fpga_tls_resync_rx(struct mlx5_core_dev *mdev, u32 handle, u32 seq,
buf->complete = mlx_tls_kfree_complete;

ret = mlx5_fpga_sbu_conn_sendmsg(mdev->fpga->tls->conn, buf);
+ if (ret < 0)
+ kfree(buf);

return ret;
}
--
2.17.1