#ifndef _AF_NETLINK_H #define _AF_NETLINK_H #include #include #include #include #define NLGRPSZ(x) (ALIGN(x, sizeof(unsigned long) * 8) / 8) #define NLGRPLONGS(x) (NLGRPSZ(x)/sizeof(unsigned long)) struct netlink_sock { /* struct sock has to be the first member of netlink_sock */ struct sock sk; u32 portid; u32 dst_portid; u32 dst_group; u32 flags; u32 subscriptions; u32 ngroups; unsigned long *groups; unsigned long state; size_t max_recvmsg_len; wait_queue_head_t wait; bool bound; bool cb_running; struct netlink_callback cb; struct mutex *cb_mutex; struct mutex cb_def_mutex; void (*netlink_rcv)(struct sk_buff *skb); int (*netlink_bind)(struct net *net, int group); void (*netlink_unbind)(struct net *net, int group); struct module *module; struct rhash_head node; struct rcu_head rcu; struct work_struct work; }; static inline struct netlink_sock *nlk_sk(struct sock *sk) { return container_of(sk, struct netlink_sock, sk); } struct netlink_table { struct rhashtable hash; struct hlist_head mc_list; struct listeners __rcu *listeners; unsigned int flags; unsigned int groups; struct mutex *cb_mutex; struct module *module; int (*bind)(struct net *net, int group); void (*unbind)(struct net *net, int group); bool (*compare)(struct net *net, struct sock *sock); int registered; }; extern struct netlink_table *nl_table; extern rwlock_t nl_table_lock; #endif it.cgi/linux/net-next.git/'>summaryrefs log tree commit diff

path: root/net/kcm

Age	Commit message (Collapse)	Author	Files	Lines
2017-02-09	kcm: fix 0-length case for kcm_sendmsg()	WANG Cong	1	-18/+22
	Dmitry reported a kernel warning: WARNING: CPU: 3 PID: 2936 at net/kcm/kcmsock.c:627 kcm_write_msgs+0x12e3/0x1b90 net/kcm/kcmsock.c:627 CPU: 3 PID: 2936 Comm: a.out Not tainted 4.10.0-rc6+ #209 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:15 [inline] dump_stack+0x2ee/0x3ef lib/dump_stack.c:51 panic+0x1fb/0x412 kernel/panic.c:179 __warn+0x1c4/0x1e0 kernel/panic.c:539 warn_slowpath_null+0x2c/0x40 kernel/panic.c:582 kcm_write_msgs+0x12e3/0x1b90 net/kcm/kcmsock.c:627 kcm_sendmsg+0x163a/0x2200 net/kcm/kcmsock.c:1029 sock_sendmsg_nosec net/socket.c:635 [inline] sock_sendmsg+0xca/0x110 net/socket.c:645 sock_write_iter+0x326/0x600 net/socket.c:848 new_sync_write fs/read_write.c:499 [inline] __vfs_write+0x483/0x740 fs/read_write.c:512 vfs_write+0x187/0x530 fs/read_write.c:560 SYSC_write fs/read_write.c:607 [inline] SyS_write+0xfb/0x230 fs/read_write.c:599 entry_SYSCALL_64_fastpath+0x1f/0xc2 when calling syscall(__NR_write, sock2, 0x208aaf27ul, 0x0ul) on a KCM seqpacket socket. It appears that kcm_sendmsg() does not handle len==0 case correctly, which causes an empty skb is allocated and queued. Fix this by skipping the skb allocation for len==0 case. Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>