Messages in this thread Patch in this message | | | Date | Wed, 01 Feb 2012 13:00:34 -0800 | From | Greg KH <> | Subject | [70/89] netns: Fail conspicously if someone uses net_generic at an inappropriate time. |
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3.2-stable review patch. If anyone has any objections, please let me know.
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From: "Eric W. Biederman" <ebiederm@xmission.com>
[ Upstream commit 5ee4433efe99b9f39f6eff5052a177bbcfe72cea ]
By definition net_generic should never be called when it can return NULL. Fail conspicously with a BUG_ON to make it clear when people mess up that a NULL return should never happen.
Recently there was a bug in the CAIF subsystem where it was registered with register_pernet_device instead of register_pernet_subsys. It was erroneously concluded that net_generic could validly return NULL and that net_assign_generic was buggy (when it was just inefficient). Hopefully this BUG_ON will prevent people to coming to similar erroneous conclusions in the futrue.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Tested-by: Sasha Levin <levinsasha928@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- include/net/netns/generic.h | 1 + 1 file changed, 1 insertion(+)
--- a/include/net/netns/generic.h +++ b/include/net/netns/generic.h @@ -41,6 +41,7 @@ static inline void *net_generic(const st ptr = ng->ptr[id - 1]; rcu_read_unlock(); + BUG_ON(!ptr); return ptr; } #endif
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