b.a.t.m.a.n.lists.open-mesh.org archive mirror
 help / color / mirror / Atom feed
From: "Linus Lüssing" <linus.luessing@c0d3.blue>
To: b.a.t.m.a.n@lists.open-mesh.org
Subject: [B.A.T.M.A.N.] [PATCHv4 maint 3/5] batman-adv: Make TT capability changes atomic
Date: Tue, 16 Jun 2015 17:10:24 +0200	[thread overview]
Message-ID: <1434467426-4281-4-git-send-email-linus.luessing@c0d3.blue> (raw)
In-Reply-To: <1434467426-4281-1-git-send-email-linus.luessing@c0d3.blue>

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: 5d2121af6d31 ("batman-adv: introduce capability initialization bitfield")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
---
 translation-table.c |    4 ++--
 types.h             |    2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/translation-table.c b/translation-table.c
index b098e53..e95a424 100644
--- a/translation-table.c
+++ b/translation-table.c
@@ -1843,7 +1843,7 @@ void batadv_tt_global_del_orig(struct batadv_priv *bat_priv,
 		}
 		spin_unlock_bh(list_lock);
 	}
-	orig_node->capa_initialized &= ~BATADV_ORIG_CAPA_HAS_TT;
+	clear_bit(BATADV_ORIG_CAPA_HAS_TT, &orig_node->capa_initialized);
 }
 
 static bool batadv_tt_global_to_purge(struct batadv_tt_global_entry *tt_global,
@@ -2802,7 +2802,7 @@ static void _batadv_tt_update_changes(struct batadv_priv *bat_priv,
 				return;
 		}
 	}
-	orig_node->capa_initialized |= BATADV_ORIG_CAPA_HAS_TT;
+	set_bit(BATADV_ORIG_CAPA_HAS_TT, &orig_node->capa_initialized);
 }
 
 static void batadv_tt_fill_gtable(struct batadv_priv *bat_priv,
diff --git a/types.h b/types.h
index e33b5aa..c6ec558 100644
--- a/types.h
+++ b/types.h
@@ -257,7 +257,7 @@ struct batadv_orig_node {
 	struct hlist_node mcast_want_all_ipv6_node;
 #endif
 	unsigned long capabilities;
-	uint8_t capa_initialized;
+	unsigned long capa_initialized;
 	atomic_t last_ttvn;
 	unsigned char *tt_buff;
 	int16_t tt_buff_len;
-- 
1.7.10.4


  parent reply	other threads:[~2015-06-16 15:10 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-06-16 15:10 [B.A.T.M.A.N.] [PATCHv4 maint 0/5] Fixes for parallel OGM processing Linus Lüssing
2015-06-16 15:10 ` [B.A.T.M.A.N.] [PATCHv4 maint 1/5] batman-adv: Make DAT capability changes atomic Linus Lüssing
2015-06-17 10:35   ` Marek Lindner
2015-06-16 15:10 ` [B.A.T.M.A.N.] [PATCHv4 maint 2/5] batman-adv: Make NC " Linus Lüssing
2015-06-17 10:37   ` Marek Lindner
2015-06-16 15:10 ` Linus Lüssing [this message]
2015-06-17 10:38   ` [B.A.T.M.A.N.] [PATCHv4 maint 3/5] batman-adv: Make TT " Marek Lindner
2015-06-16 15:10 ` [B.A.T.M.A.N.] [PATCHv4 maint 4/5] batman-adv: Make MCAST " Linus Lüssing
2015-06-17 10:39   ` Marek Lindner
2015-06-16 15:10 ` [B.A.T.M.A.N.] [PATCHv4 maint 5/5] batman-adv: Fix potential synchronization issues in mcast tvlv handler Linus Lüssing
2015-06-17 10:41   ` Marek Lindner

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1434467426-4281-4-git-send-email-linus.luessing@c0d3.blue \
    --to=linus.luessing@c0d3.blue \
    --cc=b.a.t.m.a.n@lists.open-mesh.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).