From c586bc31d5b9ae7ed202fc0dcaffbaaed77bde06 Mon Sep 17 00:00:00 2001 From: Maor Gottlieb Date: Wed, 1 Sep 2021 11:48:13 +0300 Subject: [PATCH] net/mlx5: Fix potential sleeping in atomic context commit ee27e330a953595903979ffdb84926843595a9fe upstream. 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 Signed-off-by: Maor Gottlieb Signed-off-by: Saeed Mahameed Signed-off-by: Greg Kroah-Hartman --- 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 1d4b4e6f6fb4..0ff034b0866e 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c @@ -1675,14 +1675,13 @@ 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; }