[PATCH 5.0 039/117] net: mlx5: Add a missing check on idr_find, free buf

Greg Kroah-Hartman
2019-04-15T19:10:53Z

[ Upstream commit 8e949363f017e2011464812a714fb29710fb95b4 ]

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")
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c b/drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c
index 5cf5f2a9d51f..8de64e88c670 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c
@@ -217,15 +217,21 @@ int mlx5_fpga_tls_resync_rx(struct mlx5_core_dev *mdev, u32 handle, u32 seq,
void *cmd;
int ret;

+ 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");
+ return -EINVAL;
+ }
+
buf = kzalloc(size, GFP_ATOMIC);
if (!buf)
return -ENOMEM;

cmd = (buf + 1);

- rcu_read_lock();
- flow = idr_find(&mdev->fpga->tls->rx_idr, ntohl(handle));
- rcu_read_unlock();
mlx5_fpga_tls_flow_to_cmd(flow, cmd);

MLX5_SET(tls_cmd, cmd, swid, ntohl(handle));
@@ -238,6 +244,8 @@ 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;
}
--
2.19.1