[v4,maint,2/5] batman-adv: Make NC capability changes atomic
Commit Message
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() functions.
Fixes: 7dd9d8992b0c ("batman-adv: tvlv - add network coding container")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
---
network-coding.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
Comments
On Tuesday, June 16, 2015 17:10:23 Linus Lüssing wrote:
> 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() functions.
>
> Fixes: 7dd9d8992b0c ("batman-adv: tvlv - add network coding container")
> Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
> ---
> network-coding.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
Applied in revision 586df9e.
Thanks,
Marek
@@ -105,9 +105,9 @@ static void batadv_nc_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
uint16_t tvlv_value_len)
{
if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND)
- orig->capabilities &= ~BATADV_ORIG_CAPA_HAS_NC;
+ clear_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities);
else
- orig->capabilities |= BATADV_ORIG_CAPA_HAS_NC;
+ set_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities);
}
/**