From: Thomas Graf <tgraf@suug•ch>
To: davem@davemloft•net
Cc: johannes@sipsolutions•net, netdev@vger•kernel.org
Subject: [REPOST][GENETLINK]: Fix race in genl_unregister_mc_groups()
Date: Tue, 24 Jul 2007 23:52:57 +0200 [thread overview]
Message-ID: <20070724215257.GG9285@postel.suug.ch> (raw)
In-Reply-To: <20070724094557.GE9285@postel.suug.ch>
family->mcast_groups is protected by genl_lock so it must
be held while accessing the list in genl_unregister_mc_groups().
Requires adding a non-locking variant of genl_unregister_mc_group().
Signed-off-by: Thomas Graf <tgraf@suug•ch>
Index: net-2.6/net/netlink/genetlink.c
===================================================================
--- net-2.6.orig/net/netlink/genetlink.c 2007-07-23 22:08:04.000000000 +0200
+++ net-2.6/net/netlink/genetlink.c 2007-07-24 23:51:11.000000000 +0200
@@ -200,6 +200,18 @@ int genl_register_mc_group(struct genl_f
}
EXPORT_SYMBOL(genl_register_mc_group);
+static void __genl_unregister_mc_group(struct genl_family *family,
+ struct genl_multicast_group *grp)
+{
+ BUG_ON(grp->family != family);
+ netlink_clear_multicast_users(genl_sock, grp->id);
+ clear_bit(grp->id, mc_groups);
+ list_del(&grp->list);
+ genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp);
+ grp->id = 0;
+ grp->family = NULL;
+}
+
/**
* genl_unregister_mc_group - unregister a multicast group
*
@@ -217,14 +229,8 @@ EXPORT_SYMBOL(genl_register_mc_group);
void genl_unregister_mc_group(struct genl_family *family,
struct genl_multicast_group *grp)
{
- BUG_ON(grp->family != family);
genl_lock();
- netlink_clear_multicast_users(genl_sock, grp->id);
- clear_bit(grp->id, mc_groups);
- list_del(&grp->list);
- genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp);
- grp->id = 0;
- grp->family = NULL;
+ __genl_unregister_mc_group(family, grp);
genl_unlock();
}
@@ -232,8 +238,10 @@ static void genl_unregister_mc_groups(st
{
struct genl_multicast_group *grp, *tmp;
+ genl_lock();
list_for_each_entry_safe(grp, tmp, &family->mcast_groups, list)
- genl_unregister_mc_group(family, grp);
+ __genl_unregister_mc_group(family, grp);
+ genl_unlock();
}
/**
next prev parent reply other threads:[~2007-07-24 21:52 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-07-24 9:45 [GENETLINK]: Fix race in genl_unregister_mc_groups() Thomas Graf
2007-07-24 16:14 ` Brian Haley
2007-07-24 21:51 ` Thomas Graf
2007-07-24 21:52 ` Thomas Graf [this message]
2007-07-24 22:32 ` [REPOST][GENETLINK]: " David Miller
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