From 6dc878a8ca39e93f70c42f3dd7260bde10c1e0f1 Mon Sep 17 00:00:00 2001 From: Gao feng Date: Thu, 4 Oct 2012 20:15:48 +0000 Subject: netlink: add reference of module in netlink_dump_start I get a panic when I use ss -a and rmmod inet_diag at the same time. It's because netlink_dump uses inet_diag_dump which belongs to module inet_diag. I search the codes and find many modules have the same problem. We need to add a reference to the module which the cb->dump belongs to. Thanks for all help from Stephen,Jan,Eric,Steffen and Pablo. Change From v3: change netlink_dump_start to inline,suggestion from Pablo and Eric. Change From v2: delete netlink_dump_done,and call module_put in netlink_dump and netlink_sock_destruct. Signed-off-by: Gao feng Signed-off-by: David S. Miller --- include/linux/netlink.h | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) (limited to 'include/linux/netlink.h') diff --git a/include/linux/netlink.h b/include/linux/netlink.h index f80c56ac4d82..6d3af05c107c 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -245,6 +245,8 @@ struct netlink_callback { struct netlink_callback *cb); int (*done)(struct netlink_callback *cb); void *data; + /* the module that dump function belong to */ + struct module *module; u16 family; u16 min_dump_alloc; unsigned int prev_seq, seq; @@ -262,14 +264,24 @@ __nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int fla struct netlink_dump_control { int (*dump)(struct sk_buff *skb, struct netlink_callback *); - int (*done)(struct netlink_callback*); + int (*done)(struct netlink_callback *); void *data; + struct module *module; u16 min_dump_alloc; }; -extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb, - const struct nlmsghdr *nlh, - struct netlink_dump_control *control); +extern int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb, + const struct nlmsghdr *nlh, + struct netlink_dump_control *control); +static inline int netlink_dump_start(struct sock *ssk, struct sk_buff *skb, + const struct nlmsghdr *nlh, + struct netlink_dump_control *control) +{ + if (!control->module) + control->module = THIS_MODULE; + + return __netlink_dump_start(ssk, skb, nlh, control); +} #endif /* __KERNEL__ */ -- cgit v1.2.3