[net 05/12] net/mlx5e: Destroy page pool after XDP SQ to fix use-after-free
From: Saeed Mahameed <saeed@kernel.org>
Date: 2021-08-10 03:59:51
Subsystem:
mellanox ethernet driver (mlx5e), mellanox mlx5 core vpi driver, networking drivers, the rest · Maintainers:
Saeed Mahameed, Tariq Toukan, Mark Bloch, Leon Romanovsky, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Maxim Mikityanskiy <redacted>
mlx5e_close_xdpsq does the cleanup: it calls mlx5e_free_xdpsq_descs to
free the outstanding descriptors, which relies on
mlx5e_page_release_dynamic and page_pool_release_page. However,
page_pool_destroy is already called by this point, because
mlx5e_close_rq runs before mlx5e_close_xdpsq.
This commit fixes the use-after-free by swapping mlx5e_close_xdpsq and
mlx5e_close_rq.
The commit cited below started calling page_pool_destroy directly from
the driver. Previously, the page pool was destroyed under a call_rcu
from xdp_rxq_info_unreg_mem_model, which would defer the deallocation
until after the XDPSQ is cleaned up.
Fixes: 1da4bbeffe41 ("net: core: page_pool: add user refcnt and reintroduce page_pool_destroy")
Signed-off-by: Maxim Mikityanskiy <redacted>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
.../net/ethernet/mellanox/mlx5/core/en_main.c | 20 +++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 37c440837945..fd250f7bcd88 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c@@ -1891,30 +1891,30 @@ static int mlx5e_open_queues(struct mlx5e_channel *c, if (err) goto err_close_icosq; + err = mlx5e_open_rxq_rq(c, params, &cparam->rq); + if (err) + goto err_close_sqs; + if (c->xdp) { err = mlx5e_open_xdpsq(c, params, &cparam->xdp_sq, NULL, &c->rq_xdpsq, false); if (err) - goto err_close_sqs; + goto err_close_rq; } - err = mlx5e_open_rxq_rq(c, params, &cparam->rq); - if (err) - goto err_close_xdp_sq; - err = mlx5e_open_xdpsq(c, params, &cparam->xdp_sq, NULL, &c->xdpsq, true); if (err) - goto err_close_rq; + goto err_close_xdp_sq; return 0; -err_close_rq: - mlx5e_close_rq(&c->rq); - err_close_xdp_sq: if (c->xdp) mlx5e_close_xdpsq(&c->rq_xdpsq); +err_close_rq: + mlx5e_close_rq(&c->rq); + err_close_sqs: mlx5e_close_sqs(c);
@@ -1949,9 +1949,9 @@ static int mlx5e_open_queues(struct mlx5e_channel *c, static void mlx5e_close_queues(struct mlx5e_channel *c) { mlx5e_close_xdpsq(&c->xdpsq); - mlx5e_close_rq(&c->rq); if (c->xdp) mlx5e_close_xdpsq(&c->rq_xdpsq); + mlx5e_close_rq(&c->rq); mlx5e_close_sqs(c); mlx5e_close_icosq(&c->icosq); mlx5e_close_icosq(&c->async_icosq);
--
2.31.1