netdev - [PATCH] Revert "bridge: Allow forward delay to be cfgd when STP enabled"

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1447154132-13879-1-git-send-email-vyasevich@gmail.com>
Date:	Tue, 10 Nov 2015 06:15:32 -0500
From:	Vladislav Yasevich <vyasevich@...il.com>
To:	netdev@...r.kernel.org
Cc:	stephen@...workplumber.org,
	Vladislav Yasevich <vyasevich@...il.com>,
	Vlad Yasevich <vyasevic@...hat.com>
Subject: [PATCH] Revert "bridge: Allow forward delay to be cfgd when STP enabled"

This reverts commit 34c2d9fb0498c066afbe610b15e18995fd8be792.

There are 2 reasons for this revert:
 1)  The commit in question doesn't do what it says it does.  The
     description reads: "Allow bridge forward delay to be configured
     when Spanning Tree is enabled."  This was already the case before
     the commit was made.  What the commit actually do was disallow
     invalid values or 'forward_delay' when STP was turned off.

 2)  The above change was actually a change in the user observed
     behavior and broke things like libvirt and other network configs
     that set 'forward_delay' to 0 without enabling STP.  The value
     of 0 is actually used when STP is turned off to immediately mark
     the bridge as forwarding.

Signed-off-by: Vlad Yasevich <vyasevic@...hat.com>
---
 net/bridge/br_stp.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/net/bridge/br_stp.c b/net/bridge/br_stp.c
index 80c34d7..f7e8dee 100644
--- a/net/bridge/br_stp.c
+++ b/net/bridge/br_stp.c
@@ -600,12 +600,17 @@ void __br_set_forward_delay(struct net_bridge *br, unsigned long t)
 int br_set_forward_delay(struct net_bridge *br, unsigned long val)
 {
 	unsigned long t = clock_t_to_jiffies(val);
-
-	if (t < BR_MIN_FORWARD_DELAY || t > BR_MAX_FORWARD_DELAY)
-		return -ERANGE;
+	int err = -ERANGE;
 
 	spin_lock_bh(&br->lock);
+	if (br->stp_enabled != BR_NO_STP &&
+	    (t < BR_MIN_FORWARD_DELAY || t > BR_MAX_FORWARD_DELAY))
+		goto unlock;
+
 	__br_set_forward_delay(br, t);
+	err = 0;
+
+unlock:
 	spin_unlock_bh(&br->lock);
-	return 0;
+	return err;
 }
-- 
1.9.3

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html