| From edfae7e59c985de33d2f09e4a260a0d26b376f7d Mon Sep 17 00:00:00 2001 |
| From: "Eric W. Biederman" <ebiederm@xmission.com> |
| Date: Thu, 26 Jan 2012 14:02:55 +0000 |
| Subject: netns: Fail conspicously if someone uses net_generic at an inappropriate time. |
| |
| |
| 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 |
