From: Ying Xue <ying.xue@windriver.com>
Date: Thu, 27 Mar 2014 04:54:39 +0000 (+0800)
Subject: tipc: use node list lock to protect tipc_num_links variable
X-Git-Tag: v3.15-rc1~113^2~66^2
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dde2026608fbf24e1687a2b62c4752022f429252;p=pandora-kernel.git

tipc: use node list lock to protect tipc_num_links variable

Without properly implicit or explicit read memory barrier, it's
unsafe to read an atomic variable with atomic_read() from another
thread which is different with the thread of changing the atomic
variable with atomic_inc() or atomic_dec(). So a stale tipc_num_links
may be got with atomic_read() in tipc_node_get_links(). If the
tipc_num_links variable type is converted from atomic to unsigned
integer and node list lock is used to protect it, the issue would
be avoided.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

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