From: Vlad Buslov <vladbu@mellanox.com>
Date: Tue, 6 Feb 2018 10:52:19 +0200
Subject: net/mlx5: Fix error handling when adding flow rules
Patch-mainline: v4.16-rc3
Git-commit: 9238e380e823a39983ee8d6b6ee8d1a9c4ba8a65
References: bsc#1103990 FATE#326006

If building match list or adding existing fg fails when
node is locked, function returned without unlocking it.
This happened if node version changed or adding existing fg
returned with EAGAIN after jumping to search_again_locked label.

Fixes: bd71b08ec2ee ("net/mlx5: Support multiple updates of steering rules in parallel")
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Reviewed-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlx5/core/fs_core.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c
@@ -1759,8 +1759,11 @@ search_again_locked:
 
 	/* Collect all fgs which has a matching match_criteria */
 	err = build_match_list(&match_head, ft, spec);
-	if (err)
+	if (err) {
+		if (take_write)
+			up_write_ref_node(&ft->node);
 		return ERR_PTR(err);
+	}
 
 	if (!take_write)
 		up_read_ref_node(&ft->node);
@@ -1769,8 +1772,11 @@ search_again_locked:
 				      dest_num, version);
 	free_match_list(&match_head);
 	if (!IS_ERR(rule) ||
-	    (PTR_ERR(rule) != -ENOENT && PTR_ERR(rule) != -EAGAIN))
+	    (PTR_ERR(rule) != -ENOENT && PTR_ERR(rule) != -EAGAIN)) {
+		if (take_write)
+			up_write_ref_node(&ft->node);
 		return rule;
+	}
 
 	if (!take_write) {
 		nested_down_write_ref_node(&ft->node, FS_LOCK_GRANDPARENT);