/* * NetLabel Domain Hash Table * * This file manages the domain hash table that NetLabel uses to determine * which network labeling protocol to use for a given domain. The NetLabel * system manages static and dynamic label mappings for network protocols such * as CIPSO and RIPSO. * * Author: Paul Moore * */ /* * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * 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 _NETLABEL_DOMAINHASH_H #define _NETLABEL_DOMAINHASH_H #include #include #include #include "netlabel_addrlist.h" /* Domain hash table size */ /* XXX - currently this number is an uneducated guess */ #define NETLBL_DOMHSH_BITSIZE 7 /* Domain mapping definition structures */ struct netlbl_domaddr_map { struct list_head list4; struct list_head list6; }; struct netlbl_dommap_def { u32 type; union { struct netlbl_domaddr_map *addrsel; struct cipso_v4_doi *cipso; struct calipso_doi *calipso; }; }; #define netlbl_domhsh_addr4_entry(iter) \ container_of(iter, struct netlbl_domaddr4_map, list) struct netlbl_domaddr4_map { struct netlbl_dommap_def def; struct netlbl_af4list list; }; #define netlbl_domhsh_addr6_entry(iter) \ container_of(iter, struct netlbl_domaddr6_map, list) struct netlbl_domaddr6_map { struct netlbl_dommap_def def; struct netlbl_af6list list; }; struct netlbl_dom_map { char *domain; u16 family; struct netlbl_dommap_def def; u32 valid; struct list_head list; struct rcu_head rcu; }; /* init function */ int netlbl_domhsh_init(u32 size); /* Manipulate the domain hash table */ int netlbl_domhsh_add(struct netlbl_dom_map *entry, struct netlbl_audit *audit_info); int netlbl_domhsh_add_default(struct netlbl_dom_map *entry, struct netlbl_audit *audit_info); int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry, struct netlbl_audit *audit_info); int netlbl_domhsh_remove_af4(const char *domain, const struct in_addr *addr, const struct in_addr *mask, struct netlbl_audit *audit_info); int netlbl_domhsh_remove_af6(const char *domain, const struct in6_addr *addr, const struct in6_addr *mask, struct netlbl_audit *audit_info); int netlbl_domhsh_remove(const char *domain, u16 family, struct netlbl_audit *audit_info); int netlbl_domhsh_remove_default(u16 family, struct netlbl_audit *audit_info); struct netlbl_dom_map *netlbl_domhsh_getentry(const char *domain, u16 family); struct netlbl_dommap_def *netlbl_domhsh_getentry_af4(const char *domain, __be32 addr); #if IS_ENABLED(CONFIG_IPV6) struct netlbl_dommap_def *netlbl_domhsh_getentry_af6(const char *domain, const struct in6_addr *addr); int netlbl_domhsh_remove_af6(const char *domain, const struct in6_addr *addr, const struct in6_addr *mask, struct netlbl_audit *audit_info); #endif /* IPv6 */ int netlbl_domhsh_walk(u32 *skip_bkt, u32 *skip_chain, int (*callback) (struct netlbl_dom_map *entry, void *arg), void *cb_arg); #endif ion value='7'>7space:mode:
authorDouglas 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 /tools/perf/tests/sdt.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 'tools/perf/tests/sdt.c')