/* Copyright (C) 2007-2016 B.A.T.M.A.N. contributors: * * Marek Lindner, Simon Wunderlich * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see . */ #ifndef _NET_BATMAN_ADV_SEND_H_ #define _NET_BATMAN_ADV_SEND_H_ #include "main.h" #include #include #include #include "packet.h" struct sk_buff; void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet, bool dropped); struct batadv_forw_packet * batadv_forw_packet_alloc(struct batadv_hard_iface *if_incoming, struct batadv_hard_iface *if_outgoing, atomic_t *queue_left, struct batadv_priv *bat_priv); bool batadv_forw_packet_steal(struct batadv_forw_packet *packet, spinlock_t *l); void batadv_forw_packet_ogmv1_queue(struct batadv_priv *bat_priv, struct batadv_forw_packet *forw_packet, unsigned long send_time); int batadv_send_skb_to_orig(struct sk_buff *skb, struct batadv_orig_node *orig_node, struct batadv_hard_iface *recv_if); int batadv_send_skb_packet(struct sk_buff *skb, struct batadv_hard_iface *hard_iface, const u8 *dst_addr); int batadv_send_broadcast_skb(struct sk_buff *skb, struct batadv_hard_iface *hard_iface); int batadv_send_unicast_skb(struct sk_buff *skb, struct batadv_neigh_node *neigh_node); int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv, const struct sk_buff *skb, unsigned long delay, bool own_packet); void batadv_purge_outstanding_packets(struct batadv_priv *bat_priv, const struct batadv_hard_iface *hard_iface); bool batadv_send_skb_prepare_unicast_4addr(struct batadv_priv *bat_priv, struct sk_buff *skb, struct batadv_orig_node *orig_node, int packet_subtype); int batadv_send_skb_unicast(struct batadv_priv *bat_priv, struct sk_buff *skb, int packet_type, int packet_subtype, struct batadv_orig_node *orig_node, unsigned short vid); int batadv_send_skb_via_tt_generic(struct batadv_priv *bat_priv, struct sk_buff *skb, int packet_type, int packet_subtype, u8 *dst_hint, unsigned short vid); int batadv_send_skb_via_gw(struct batadv_priv *bat_priv, struct sk_buff *skb, unsigned short vid); /** * batadv_send_skb_via_tt - send an skb via TT lookup * @bat_priv: the bat priv with all the soft interface information * @skb: the payload to send * @dst_hint: can be used to override the destination contained in the skb * @vid: the vid to be used to search the translation table * * Look up the recipient node for the destination address in the ethernet * header via the translation table. Wrap the given skb into a batman-adv * unicast header. Then send this frame to the according destination node. * * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise. */ static inline int batadv_send_skb_via_tt(struct batadv_priv *bat_priv, struct sk_buff *skb, u8 *dst_hint, unsigned short vid) { return batadv_send_skb_via_tt_generic(bat_priv, skb, BATADV_UNICAST, 0, dst_hint, vid); } /** * batadv_send_skb_via_tt_4addr - send an skb via TT lookup * @bat_priv: the bat priv with all the soft interface information * @skb: the payload to send * @packet_subtype: the unicast 4addr packet subtype to use * @dst_hint: can be used to override the destination contained in the skb * @vid: the vid to be used to search the translation table * * Look up the recipient node for the destination address in the ethernet * header via the translation table. Wrap the given skb into a batman-adv * unicast-4addr header. Then send this frame to the according destination * node. * * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise. */ static inline int batadv_send_skb_via_tt_4addr(struct batadv_priv *bat_priv, struct sk_buff *skb, int packet_subtype, u8 *dst_hint, unsigned short vid) { return batadv_send_skb_via_tt_generic(bat_priv, skb, BATADV_UNICAST_4ADDR, packet_subtype, dst_hint, vid); } #endif /* _NET_BATMAN_ADV_SEND_H_ */ h>Douglas Miller <dougmill@linux.vnet.ibm.com>2017-01-28 06:42:20 -0600 committerTejun Heo <tj@kernel.org>2017-01-28 07:49:42 -0500 commit966d2b04e070bc040319aaebfec09e0144dc3341 (patch) tree4b96156e3d1dd4dfd6039b7c219c9dc4616da52d /net/openvswitch/vport-geneve.c parent1b1bc42c1692e9b62756323c675a44cb1a1f9dbd (diff)
percpu-refcount: fix reference leak during percpu-atomic transition
percpu_ref_tryget() and percpu_ref_tryget_live() should return "true" IFF they acquire a reference. But the return value from atomic_long_inc_not_zero() is a long and may have high bits set, e.g. PERCPU_COUNT_BIAS, and the return value of the tryget routines is bool so the reference may actually be acquired but the routines return "false" which results in a reference leak since the caller assumes it does not need to do a corresponding percpu_ref_put(). This was seen when performing CPU hotplug during I/O, as hangs in blk_mq_freeze_queue_wait where percpu_ref_kill (blk_mq_freeze_queue_start) raced with percpu_ref_tryget (blk_mq_timeout_work). Sample stack trace: __switch_to+0x2c0/0x450 __schedule+0x2f8/0x970 schedule+0x48/0xc0 blk_mq_freeze_queue_wait+0x94/0x120 blk_mq_queue_reinit_work+0xb8/0x180 blk_mq_queue_reinit_prepare+0x84/0xa0 cpuhp_invoke_callback+0x17c/0x600 cpuhp_up_callbacks+0x58/0x150 _cpu_up+0xf0/0x1c0 do_cpu_up+0x120/0x150 cpu_subsys_online+0x64/0xe0 device_online+0xb4/0x120 online_store+0xb4/0xc0 dev_attr_store+0x68/0xa0 sysfs_kf_write+0x80/0xb0 kernfs_fop_write+0x17c/0x250 __vfs_write+0x6c/0x1e0 vfs_write+0xd0/0x270 SyS_write+0x6c/0x110 system_call+0x38/0xe0 Examination of the queue showed a single reference (no PERCPU_COUNT_BIAS, and __PERCPU_REF_DEAD, __PERCPU_REF_ATOMIC set) and no requests. However, conditions at the time of the race are count of PERCPU_COUNT_BIAS + 0 and __PERCPU_REF_DEAD and __PERCPU_REF_ATOMIC set. The fix is to make the tryget routines use an actual boolean internally instead of the atomic long result truncated to a int. Fixes: e625305b3907 percpu-refcount: make percpu_ref based on longs instead of ints Link: https://bugzilla.kernel.org/show_bug.cgi?id=190751 Signed-off-by: Douglas Miller <dougmill@linux.vnet.ibm.com> Reviewed-by: Jens Axboe <axboe@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: e625305b3907 ("percpu-refcount: make percpu_ref based on longs instead of ints") Cc: stable@vger.kernel.org # v3.18+
Diffstat (limited to 'net/openvswitch/vport-geneve.c')