Re: [PATCH 04/10] batman-adv: Make NC capability changes atomic

From: Linus Lüssing <redacted>

Bitwise OR/AND assignments in C aren't guaranteed to be atomic. One
OGM handler might undo the set/clear of a specific bit from another
handler run in between.

Fix this by using the atomic set_bit()/clear_bit()/test_bit() functions.

Fixes: 3f4841ffb336 ("batman-adv: tvlv - add network coding container")
Signed-off-by: Linus Lüssing <redacted>
Signed-off-by: Marek Lindner <redacted>
Signed-off-by: Antonio Quartulli <redacted>
---
  net/batman-adv/network-coding.c | 7 ++++---
  net/batman-adv/types.h          | 2 +-
  2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/net/batman-adv/network-coding.c b/net/batman-adv/network-coding.c
index f0a50f3..cfdc80d 100644
--- a/net/batman-adv/network-coding.c
+++ b/net/batman-adv/network-coding.c

@@ -894,7 +895,7 @@ void batadv_nc_update_nc_node(struct batadv_priv *bat_priv,
  		goto out;

  	/* check if orig node is network coding enabled */
-	if (!(orig_node->capabilities & BATADV_ORIG_CAPA_HAS_NC))
+	if (!(test_bit(BATADV_ORIG_CAPA_HAS_NC, &orig_node->capabilities)))