From: Linus Torvalds Date: Thu, 17 Feb 2011 22:54:38 +0000 (+0000) Subject: net: dont leave active on stack LIST_HEAD X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=f87e6f47933e3ebeced9bb12615e830a72cedce4;p=linux-beck.git net: dont leave active on stack LIST_HEAD Eric W. Biderman and Michal Hocko reported various memory corruptions that we suspected to be related to a LIST head located on stack, that was manipulated after thread left function frame (and eventually exited, so its stack was freed and reused). Eric Dumazet suggested the problem was probably coming from commit 443457242beb (net: factorize sync-rcu call in unregister_netdevice_many) This patch fixes __dev_close() and dev_close() to properly deinit their respective LIST_HEAD(single) before exiting. References: https://lkml.org/lkml/2011/2/16/304 References: https://lkml.org/lkml/2011/2/14/223 Reported-by: Michal Hocko Tested-by: Michal Hocko Reported-by: Eric W. Biderman Tested-by: Eric W. Biderman Signed-off-by: Linus Torvalds Signed-off-by: Eric Dumazet CC: Ingo Molnar CC: Octavian Purdila Signed-off-by: David S. Miller --- diff --git a/net/core/dev.c b/net/core/dev.c index 8e726cb47ed7..a18c1643ea9f 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1280,10 +1280,13 @@ static int __dev_close_many(struct list_head *head) static int __dev_close(struct net_device *dev) { + int retval; LIST_HEAD(single); list_add(&dev->unreg_list, &single); - return __dev_close_many(&single); + retval = __dev_close_many(&single); + list_del(&single); + return retval; } int dev_close_many(struct list_head *head) @@ -1325,7 +1328,7 @@ int dev_close(struct net_device *dev) list_add(&dev->unreg_list, &single); dev_close_many(&single); - + list_del(&single); return 0; } EXPORT_SYMBOL(dev_close);