[net 5/7] net/mlx5: Fix potential sleeping in atomic context
From: Saeed Mahameed <saeed@kernel.org>
Date: 2021-09-07 21:24:41
Subsystem:
mellanox mlx5 core vpi driver, networking drivers, the rest · Maintainers:
Saeed Mahameed, Leon Romanovsky, Tariq Toukan, Mark Bloch, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Maor Gottlieb <redacted>
Fixes the below flow of sleeping in atomic context by releasing
the RCU lock before calling to free_match_list.
build_match_list() <- disables preempt
-> free_match_list()
-> tree_put_node()
-> down_write_ref_node() <- take write lock
Fixes: 693c6883bbc4 ("net/mlx5: Add hash table for flow groups in flow table")
Reported-by: Dan Carpenter <redacted>
Signed-off-by: Maor Gottlieb <redacted>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
drivers/net/ethernet/mellanox/mlx5/core/fs_core.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c
index 9fe8e3c204d6..fe501ba88bea 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c@@ -1682,14 +1682,13 @@ static int build_match_list(struct match_list *match_head, curr_match = kmalloc(sizeof(*curr_match), GFP_ATOMIC); if (!curr_match) { + rcu_read_unlock(); free_match_list(match_head, ft_locked); - err = -ENOMEM; - goto out; + return -ENOMEM; } curr_match->g = g; list_add_tail(&curr_match->list, &match_head->list); } -out: rcu_read_unlock(); return err; }
--
2.31.1