On 01/21/15 at 04:13pm, Ying Xue wrote:

On 01/20/2015 09:20 PM, Thomas Graf wrote:

quoted

A deferred resize of nl_table causes the offsets that Netlink diag keeps
to become inaccurate. Mark the dump as inconsistent and have user space
request a new dump.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
---
 net/netlink/af_netlink.c | 10 ++++++++++
 net/netlink/af_netlink.h |  1 +
 net/netlink/diag.c       |  1 +
 3 files changed, 12 insertions(+)

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 7a94185..e214557 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c

@@ -91,6 +91,9 @@ static inline int netlink_is_kernel(struct sock *sk)
 struct netlink_table *nl_table;
 EXPORT_SYMBOL_GPL(nl_table);
 
+atomic_t nl_table_seq;

It sounds like the atomic variable is not initialized.

Thanks for the review. We also need to avoid hitting 0 when we overflow
on a seq increment.  The netfilter code is doing this correctly but several
other users are suffering from this as well.

I'll address this in v2 together with the other discussed changes.