Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/ipc/util.c |
| 3 | * Copyright (C) 1992 Krishna Balasubramanian |
| 4 | * |
| 5 | * Sep 1997 - Call suser() last after "normal" permission checks so we |
| 6 | * get BSD style process accounting right. |
| 7 | * Occurs in several places in the IPC code. |
| 8 | * Chris Evans, <chris@ferret.lmh.ox.ac.uk> |
| 9 | * Nov 1999 - ipc helper functions, unified SMP locking |
Christian Kujau | 624dffc | 2006-01-15 02:43:54 +0100 | [diff] [blame] | 10 | * Manfred Spraul <manfred@colorfullife.com> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | * Oct 2002 - One lock per IPC id. RCU ipc_free for lock-free grow_ary(). |
| 12 | * Mingming Cao <cmm@us.ibm.com> |
Steve Grubb | 073115d | 2006-04-02 17:07:33 -0400 | [diff] [blame] | 13 | * Mar 2006 - support for audit of ipc object properties |
| 14 | * Dustin Kirkland <dustin.kirkland@us.ibm.com> |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 15 | * Jun 2006 - namespaces ssupport |
| 16 | * OpenVZ, SWsoft Inc. |
| 17 | * Pavel Emelianov <xemul@openvz.org> |
Davidlohr Bueso | 05603c4 | 2013-09-11 14:26:26 -0700 | [diff] [blame] | 18 | * |
| 19 | * General sysv ipc locking scheme: |
Davidlohr Bueso | 18ccee2 | 2013-10-16 13:46:45 -0700 | [diff] [blame] | 20 | * rcu_read_lock() |
| 21 | * obtain the ipc object (kern_ipc_perm) by looking up the id in an idr |
| 22 | * tree. |
| 23 | * - perform initial checks (capabilities, auditing and permission, |
| 24 | * etc). |
| 25 | * - perform read-only operations, such as STAT, INFO commands. |
| 26 | * acquire the ipc lock (kern_ipc_perm.lock) through |
| 27 | * ipc_lock_object() |
| 28 | * - perform data updates, such as SET, RMID commands and |
| 29 | * mechanism-specific operations (semop/semtimedop, |
| 30 | * msgsnd/msgrcv, shmat/shmdt). |
| 31 | * drop the ipc lock, through ipc_unlock_object(). |
| 32 | * rcu_read_unlock() |
| 33 | * |
| 34 | * The ids->rwsem must be taken when: |
| 35 | * - creating, removing and iterating the existing entries in ipc |
| 36 | * identifier sets. |
| 37 | * - iterating through files under /proc/sysvipc/ |
| 38 | * |
| 39 | * Note that sems have a special fast path that avoids kern_ipc_perm.lock - |
| 40 | * see sem_lock(). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | */ |
| 42 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | #include <linux/mm.h> |
| 44 | #include <linux/shm.h> |
| 45 | #include <linux/init.h> |
| 46 | #include <linux/msg.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | #include <linux/vmalloc.h> |
| 48 | #include <linux/slab.h> |
Andrew Morton | 8f68fa2 | 2013-04-29 15:08:05 -0700 | [diff] [blame] | 49 | #include <linux/notifier.h> |
Randy.Dunlap | c59ede7 | 2006-01-11 12:17:46 -0800 | [diff] [blame] | 50 | #include <linux/capability.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | #include <linux/highuid.h> |
| 52 | #include <linux/security.h> |
| 53 | #include <linux/rcupdate.h> |
| 54 | #include <linux/workqueue.h> |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 55 | #include <linux/seq_file.h> |
| 56 | #include <linux/proc_fs.h> |
Steve Grubb | 073115d | 2006-04-02 17:07:33 -0400 | [diff] [blame] | 57 | #include <linux/audit.h> |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 58 | #include <linux/nsproxy.h> |
Nadia Derbey | 3e148c7 | 2007-10-18 23:40:54 -0700 | [diff] [blame] | 59 | #include <linux/rwsem.h> |
Nadia Derbey | b6b337a | 2008-04-29 01:00:42 -0700 | [diff] [blame] | 60 | #include <linux/memory.h> |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 61 | #include <linux/ipc_namespace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | |
| 63 | #include <asm/unistd.h> |
| 64 | |
| 65 | #include "util.h" |
| 66 | |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 67 | struct ipc_proc_iface { |
| 68 | const char *path; |
| 69 | const char *header; |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 70 | int ids; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 71 | int (*show)(struct seq_file *, void *); |
| 72 | }; |
| 73 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 75 | * ipc_init - initialise ipc subsystem |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 77 | * The various sysv ipc resources (semaphores, messages and shared |
| 78 | * memory) are initialised. |
| 79 | * |
| 80 | * A callback routine is registered into the memory hotplug notifier |
| 81 | * chain: since msgmni scales to lowmem this callback routine will be |
| 82 | * called upon successful memory add / remove to recompute msmgni. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | static int __init ipc_init(void) |
| 85 | { |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 86 | int err_sem, err_msg; |
| 87 | |
| 88 | err_sem = sem_init(); |
| 89 | WARN(err_sem, "ipc: sysv sem_init failed: %d\n", err_sem); |
| 90 | err_msg = msg_init(); |
| 91 | WARN(err_msg, "ipc: sysv msg_init failed: %d\n", err_msg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 92 | shm_init(); |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 93 | |
| 94 | return err_msg ? err_msg : err_sem; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 95 | } |
Davidlohr Bueso | 6d08a25 | 2014-04-07 15:39:18 -0700 | [diff] [blame] | 96 | device_initcall(ipc_init); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 98 | static const struct rhashtable_params ipc_kht_params = { |
| 99 | .head_offset = offsetof(struct kern_ipc_perm, khtnode), |
| 100 | .key_offset = offsetof(struct kern_ipc_perm, key), |
| 101 | .key_len = FIELD_SIZEOF(struct kern_ipc_perm, key), |
| 102 | .locks_mul = 1, |
| 103 | .automatic_shrinking = true, |
| 104 | }; |
| 105 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 107 | * ipc_init_ids - initialise ipc identifiers |
| 108 | * @ids: ipc identifier set |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 110 | * Set up the sequence range to use for the ipc identifier range (limited |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 111 | * below IPCMNI) then initialise the keys hashtable and ids idr. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | */ |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 113 | int ipc_init_ids(struct ipc_ids *ids) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | { |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 115 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | ids->in_use = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | ids->seq = 0; |
Stanislav Kinsbursky | 03f5956 | 2013-01-04 15:34:50 -0800 | [diff] [blame] | 118 | ids->next_id = -1; |
Davidlohr Bueso | daf948c | 2014-01-27 17:07:09 -0800 | [diff] [blame] | 119 | init_rwsem(&ids->rwsem); |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 120 | err = rhashtable_init(&ids->key_ht, &ipc_kht_params); |
| 121 | if (err) |
| 122 | return err; |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 123 | idr_init(&ids->ipcs_idr); |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 124 | ids->tables_initialized = true; |
| 125 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | } |
| 127 | |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 128 | #ifdef CONFIG_PROC_FS |
Arjan van de Ven | 9a32144 | 2007-02-12 00:55:35 -0800 | [diff] [blame] | 129 | static const struct file_operations sysvipc_proc_fops; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 130 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 131 | * ipc_init_proc_interface - create a proc interface for sysipc types using a seq_file interface. |
| 132 | * @path: Path in procfs |
| 133 | * @header: Banner to be printed at the beginning of the file. |
| 134 | * @ids: ipc id table to iterate. |
| 135 | * @show: show routine. |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 136 | */ |
| 137 | void __init ipc_init_proc_interface(const char *path, const char *header, |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 138 | int ids, int (*show)(struct seq_file *, void *)) |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 139 | { |
| 140 | struct proc_dir_entry *pde; |
| 141 | struct ipc_proc_iface *iface; |
| 142 | |
| 143 | iface = kmalloc(sizeof(*iface), GFP_KERNEL); |
| 144 | if (!iface) |
| 145 | return; |
| 146 | iface->path = path; |
| 147 | iface->header = header; |
| 148 | iface->ids = ids; |
| 149 | iface->show = show; |
| 150 | |
Denis V. Lunev | 6a6375d | 2008-04-29 01:02:12 -0700 | [diff] [blame] | 151 | pde = proc_create_data(path, |
| 152 | S_IRUGO, /* world readable */ |
| 153 | NULL, /* parent dir */ |
| 154 | &sysvipc_proc_fops, |
| 155 | iface); |
Davidlohr Bueso | 3ab08fe | 2014-01-27 17:07:06 -0800 | [diff] [blame] | 156 | if (!pde) |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 157 | kfree(iface); |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 158 | } |
| 159 | #endif |
| 160 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 161 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 162 | * ipc_findkey - find a key in an ipc identifier set |
| 163 | * @ids: ipc identifier set |
| 164 | * @key: key to find |
Paul McQuade | 46c0a8c | 2014-06-06 14:37:37 -0700 | [diff] [blame] | 165 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 166 | * Returns the locked pointer to the ipc structure if found or NULL |
| 167 | * otherwise. If key is found ipc points to the owning ipc structure |
| 168 | * |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 169 | * Called with writer ipc_ids.rwsem held. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 170 | */ |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 171 | static struct kern_ipc_perm *ipc_findkey(struct ipc_ids *ids, key_t key) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | { |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 173 | struct kern_ipc_perm *ipcp = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 175 | if (likely(ids->tables_initialized)) |
| 176 | ipcp = rhashtable_lookup_fast(&ids->key_ht, &key, |
| 177 | ipc_kht_params); |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 178 | |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 179 | if (ipcp) { |
Davidlohr Bueso | 32a2750 | 2013-09-11 14:26:29 -0700 | [diff] [blame] | 180 | rcu_read_lock(); |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 181 | ipc_lock_object(ipcp); |
| 182 | return ipcp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | } |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 184 | |
| 185 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 186 | } |
| 187 | |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 188 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 189 | * ipc_get_maxid - get the last assigned id |
| 190 | * @ids: ipc identifier set |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 191 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 192 | * Called with ipc_ids.rwsem held. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | */ |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 194 | int ipc_get_maxid(struct ipc_ids *ids) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 195 | { |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 196 | struct kern_ipc_perm *ipc; |
| 197 | int max_id = -1; |
| 198 | int total, id; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 200 | if (ids->in_use == 0) |
| 201 | return -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 202 | |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 203 | if (ids->in_use == IPCMNI) |
| 204 | return IPCMNI - 1; |
| 205 | |
| 206 | /* Look for the last assigned id */ |
| 207 | total = 0; |
| 208 | for (id = 0; id < IPCMNI && total < ids->in_use; id++) { |
| 209 | ipc = idr_find(&ids->ipcs_idr, id); |
| 210 | if (ipc != NULL) { |
| 211 | max_id = id; |
| 212 | total++; |
| 213 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | } |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 215 | return max_id; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 216 | } |
| 217 | |
| 218 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 219 | * ipc_addid - add an ipc identifier |
| 220 | * @ids: ipc identifier set |
| 221 | * @new: new ipc permission set |
| 222 | * @size: limit for the number of used ids |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 224 | * Add an entry 'new' to the ipc ids idr. The permissions object is |
| 225 | * initialised and the first free entry is set up and the id assigned |
| 226 | * is returned. The 'new' entry is returned in a locked state on success. |
| 227 | * On failure the entry is not locked and a negative err-code is returned. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 229 | * Called with writer ipc_ids.rwsem held. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | */ |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 231 | int ipc_addid(struct ipc_ids *ids, struct kern_ipc_perm *new, int size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 232 | { |
Eric W. Biederman | 1efdb69 | 2012-02-07 16:54:11 -0800 | [diff] [blame] | 233 | kuid_t euid; |
| 234 | kgid_t egid; |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 235 | int id, err; |
Stanislav Kinsbursky | 03f5956 | 2013-01-04 15:34:50 -0800 | [diff] [blame] | 236 | int next_id = ids->next_id; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 238 | if (size > IPCMNI) |
| 239 | size = IPCMNI; |
| 240 | |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 241 | if (!ids->tables_initialized || ids->in_use >= size) |
Pierre Peiffer | 283bb7f | 2007-10-18 23:40:57 -0700 | [diff] [blame] | 242 | return -ENOSPC; |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 243 | |
Tejun Heo | 54924ea | 2013-02-27 17:04:53 -0800 | [diff] [blame] | 244 | idr_preload(GFP_KERNEL); |
| 245 | |
Elena Reshetova | 9405c03 | 2017-09-08 16:17:45 -0700 | [diff] [blame] | 246 | refcount_set(&new->refcount, 1); |
Nadia Derbey | e00b4ff7e | 2008-11-19 15:36:08 -0800 | [diff] [blame] | 247 | spin_lock_init(&new->lock); |
Rafael Aquini | 72a8ff2 | 2014-01-27 17:07:02 -0800 | [diff] [blame] | 248 | new->deleted = false; |
Nadia Derbey | e00b4ff7e | 2008-11-19 15:36:08 -0800 | [diff] [blame] | 249 | rcu_read_lock(); |
| 250 | spin_lock(&new->lock); |
| 251 | |
Linus Torvalds | b9a5322 | 2015-09-30 12:48:40 -0400 | [diff] [blame] | 252 | current_euid_egid(&euid, &egid); |
| 253 | new->cuid = new->uid = euid; |
| 254 | new->gid = new->cgid = egid; |
| 255 | |
Tejun Heo | 54924ea | 2013-02-27 17:04:53 -0800 | [diff] [blame] | 256 | id = idr_alloc(&ids->ipcs_idr, new, |
| 257 | (next_id < 0) ? 0 : ipcid_to_idx(next_id), 0, |
| 258 | GFP_NOWAIT); |
| 259 | idr_preload_end(); |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 260 | |
| 261 | if (id >= 0 && new->key != IPC_PRIVATE) { |
| 262 | err = rhashtable_insert_fast(&ids->key_ht, &new->khtnode, |
| 263 | ipc_kht_params); |
| 264 | if (err < 0) { |
| 265 | idr_remove(&ids->ipcs_idr, id); |
| 266 | id = err; |
| 267 | } |
| 268 | } |
Tejun Heo | 54924ea | 2013-02-27 17:04:53 -0800 | [diff] [blame] | 269 | if (id < 0) { |
Nadia Derbey | e00b4ff7e | 2008-11-19 15:36:08 -0800 | [diff] [blame] | 270 | spin_unlock(&new->lock); |
| 271 | rcu_read_unlock(); |
Tejun Heo | 54924ea | 2013-02-27 17:04:53 -0800 | [diff] [blame] | 272 | return id; |
Nadia Derbey | e00b4ff7e | 2008-11-19 15:36:08 -0800 | [diff] [blame] | 273 | } |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 274 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | ids->in_use++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 276 | |
Stanislav Kinsbursky | 03f5956 | 2013-01-04 15:34:50 -0800 | [diff] [blame] | 277 | if (next_id < 0) { |
| 278 | new->seq = ids->seq++; |
Davidlohr Bueso | daf948c | 2014-01-27 17:07:09 -0800 | [diff] [blame] | 279 | if (ids->seq > IPCID_SEQ_MAX) |
Stanislav Kinsbursky | 03f5956 | 2013-01-04 15:34:50 -0800 | [diff] [blame] | 280 | ids->seq = 0; |
| 281 | } else { |
| 282 | new->seq = ipcid_to_seqx(next_id); |
| 283 | ids->next_id = -1; |
| 284 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 285 | |
Pierre Peiffer | 48dea40 | 2008-04-29 01:00:35 -0700 | [diff] [blame] | 286 | new->id = ipc_buildid(id, new->seq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 287 | return id; |
| 288 | } |
| 289 | |
| 290 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 291 | * ipcget_new - create a new ipc object |
| 292 | * @ns: ipc namespace |
Masanari Iida | da3dae5 | 2014-09-09 01:27:23 +0900 | [diff] [blame] | 293 | * @ids: ipc identifier set |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 294 | * @ops: the actual creation routine to call |
| 295 | * @params: its parameters |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 296 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 297 | * This routine is called by sys_msgget, sys_semget() and sys_shmget() |
| 298 | * when the key is IPC_PRIVATE. |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 299 | */ |
Pavel Emelyanov | b2d75cd | 2008-02-08 04:18:54 -0800 | [diff] [blame] | 300 | static int ipcget_new(struct ipc_namespace *ns, struct ipc_ids *ids, |
Mathias Krause | eb66ec4 | 2014-06-06 14:37:36 -0700 | [diff] [blame] | 301 | const struct ipc_ops *ops, struct ipc_params *params) |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 302 | { |
| 303 | int err; |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 304 | |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 305 | down_write(&ids->rwsem); |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 306 | err = ops->getnew(ns, params); |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 307 | up_write(&ids->rwsem); |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 308 | return err; |
| 309 | } |
| 310 | |
| 311 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 312 | * ipc_check_perms - check security and permissions for an ipc object |
| 313 | * @ns: ipc namespace |
| 314 | * @ipcp: ipc permission set |
| 315 | * @ops: the actual security routine to call |
| 316 | * @params: its parameters |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 317 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 318 | * This routine is called by sys_msgget(), sys_semget() and sys_shmget() |
| 319 | * when the key is not IPC_PRIVATE and that key already exists in the |
| 320 | * ds IDR. |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 321 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 322 | * On success, the ipc id is returned. |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 323 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 324 | * It is called with ipc_ids.rwsem and ipcp->lock held. |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 325 | */ |
Serge E. Hallyn | b0e7759 | 2011-03-23 16:43:24 -0700 | [diff] [blame] | 326 | static int ipc_check_perms(struct ipc_namespace *ns, |
| 327 | struct kern_ipc_perm *ipcp, |
Mathias Krause | eb66ec4 | 2014-06-06 14:37:36 -0700 | [diff] [blame] | 328 | const struct ipc_ops *ops, |
Serge E. Hallyn | b0e7759 | 2011-03-23 16:43:24 -0700 | [diff] [blame] | 329 | struct ipc_params *params) |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 330 | { |
| 331 | int err; |
| 332 | |
Serge E. Hallyn | b0e7759 | 2011-03-23 16:43:24 -0700 | [diff] [blame] | 333 | if (ipcperms(ns, ipcp, params->flg)) |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 334 | err = -EACCES; |
| 335 | else { |
| 336 | err = ops->associate(ipcp, params->flg); |
| 337 | if (!err) |
| 338 | err = ipcp->id; |
| 339 | } |
| 340 | |
| 341 | return err; |
| 342 | } |
| 343 | |
| 344 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 345 | * ipcget_public - get an ipc object or create a new one |
| 346 | * @ns: ipc namespace |
Masanari Iida | da3dae5 | 2014-09-09 01:27:23 +0900 | [diff] [blame] | 347 | * @ids: ipc identifier set |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 348 | * @ops: the actual creation routine to call |
| 349 | * @params: its parameters |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 350 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 351 | * This routine is called by sys_msgget, sys_semget() and sys_shmget() |
| 352 | * when the key is not IPC_PRIVATE. |
| 353 | * It adds a new entry if the key is not found and does some permission |
| 354 | * / security checkings if the key is found. |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 355 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 356 | * On success, the ipc id is returned. |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 357 | */ |
Pavel Emelyanov | b2d75cd | 2008-02-08 04:18:54 -0800 | [diff] [blame] | 358 | static int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids, |
Mathias Krause | eb66ec4 | 2014-06-06 14:37:36 -0700 | [diff] [blame] | 359 | const struct ipc_ops *ops, struct ipc_params *params) |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 360 | { |
| 361 | struct kern_ipc_perm *ipcp; |
| 362 | int flg = params->flg; |
| 363 | int err; |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 364 | |
Nadia Derbey | 3e148c7 | 2007-10-18 23:40:54 -0700 | [diff] [blame] | 365 | /* |
| 366 | * Take the lock as a writer since we are potentially going to add |
| 367 | * a new entry + read locks are not "upgradable" |
| 368 | */ |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 369 | down_write(&ids->rwsem); |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 370 | ipcp = ipc_findkey(ids, params->key); |
| 371 | if (ipcp == NULL) { |
| 372 | /* key not used */ |
| 373 | if (!(flg & IPC_CREAT)) |
| 374 | err = -ENOENT; |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 375 | else |
| 376 | err = ops->getnew(ns, params); |
| 377 | } else { |
| 378 | /* ipc object has been locked by ipc_findkey() */ |
| 379 | |
| 380 | if (flg & IPC_CREAT && flg & IPC_EXCL) |
| 381 | err = -EEXIST; |
| 382 | else { |
| 383 | err = 0; |
| 384 | if (ops->more_checks) |
| 385 | err = ops->more_checks(ipcp, params); |
| 386 | if (!err) |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 387 | /* |
| 388 | * ipc_check_perms returns the IPC id on |
| 389 | * success |
| 390 | */ |
Serge E. Hallyn | b0e7759 | 2011-03-23 16:43:24 -0700 | [diff] [blame] | 391 | err = ipc_check_perms(ns, ipcp, ops, params); |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 392 | } |
| 393 | ipc_unlock(ipcp); |
| 394 | } |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 395 | up_write(&ids->rwsem); |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 396 | |
| 397 | return err; |
| 398 | } |
| 399 | |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 400 | /** |
| 401 | * ipc_kht_remove - remove an ipc from the key hashtable |
| 402 | * @ids: ipc identifier set |
| 403 | * @ipcp: ipc perm structure containing the key to remove |
| 404 | * |
| 405 | * ipc_ids.rwsem (as a writer) and the spinlock for this ID are held |
| 406 | * before this function is called, and remain locked on the exit. |
| 407 | */ |
| 408 | static void ipc_kht_remove(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) |
| 409 | { |
| 410 | if (ipcp->key != IPC_PRIVATE) |
| 411 | rhashtable_remove_fast(&ids->key_ht, &ipcp->khtnode, |
| 412 | ipc_kht_params); |
| 413 | } |
Nadia Derbey | 7748dbf | 2007-10-18 23:40:49 -0700 | [diff] [blame] | 414 | |
| 415 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 416 | * ipc_rmid - remove an ipc identifier |
| 417 | * @ids: ipc identifier set |
| 418 | * @ipcp: ipc perm structure containing the identifier to remove |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 419 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 420 | * ipc_ids.rwsem (as a writer) and the spinlock for this ID are held |
| 421 | * before this function is called, and remain locked on the exit. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 422 | */ |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 423 | void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 424 | { |
Nadia Derbey | ce621f5 | 2007-10-18 23:40:52 -0700 | [diff] [blame] | 425 | int lid = ipcid_to_idx(ipcp->id); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 426 | |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 427 | idr_remove(&ids->ipcs_idr, lid); |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 428 | ipc_kht_remove(ids, ipcp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 429 | ids->in_use--; |
Rafael Aquini | 72a8ff2 | 2014-01-27 17:07:02 -0800 | [diff] [blame] | 430 | ipcp->deleted = true; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | } |
| 432 | |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 433 | /** |
| 434 | * ipc_set_key_private - switch the key of an existing ipc to IPC_PRIVATE |
| 435 | * @ids: ipc identifier set |
| 436 | * @ipcp: ipc perm structure containing the key to modify |
| 437 | * |
| 438 | * ipc_ids.rwsem (as a writer) and the spinlock for this ID are held |
| 439 | * before this function is called, and remain locked on the exit. |
| 440 | */ |
| 441 | void ipc_set_key_private(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) |
| 442 | { |
| 443 | ipc_kht_remove(ids, ipcp); |
| 444 | ipcp->key = IPC_PRIVATE; |
| 445 | } |
| 446 | |
Manfred Spraul | dba4cdd | 2017-07-12 14:34:41 -0700 | [diff] [blame] | 447 | int ipc_rcu_getref(struct kern_ipc_perm *ptr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | { |
Elena Reshetova | 9405c03 | 2017-09-08 16:17:45 -0700 | [diff] [blame] | 449 | return refcount_inc_not_zero(&ptr->refcount); |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 450 | } |
| 451 | |
Manfred Spraul | dba4cdd | 2017-07-12 14:34:41 -0700 | [diff] [blame] | 452 | void ipc_rcu_putref(struct kern_ipc_perm *ptr, |
| 453 | void (*func)(struct rcu_head *head)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | { |
Elena Reshetova | 9405c03 | 2017-09-08 16:17:45 -0700 | [diff] [blame] | 455 | if (!refcount_dec_and_test(&ptr->refcount)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 456 | return; |
| 457 | |
Manfred Spraul | dba4cdd | 2017-07-12 14:34:41 -0700 | [diff] [blame] | 458 | call_rcu(&ptr->rcu, func); |
Davidlohr Bueso | 53dad6d | 2013-09-23 17:04:45 -0700 | [diff] [blame] | 459 | } |
| 460 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 461 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 462 | * ipcperms - check ipc permissions |
| 463 | * @ns: ipc namespace |
| 464 | * @ipcp: ipc permission set |
| 465 | * @flag: desired permission set |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 467 | * Check user, group, other permissions for access |
| 468 | * to ipc resources. return 0 if allowed |
Serge E. Hallyn | b0e7759 | 2011-03-23 16:43:24 -0700 | [diff] [blame] | 469 | * |
mchehab@s-opensource.com | 0e056eb | 2017-03-30 17:11:36 -0300 | [diff] [blame] | 470 | * @flag will most probably be 0 or ``S_...UGO`` from <linux/stat.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 471 | */ |
Serge E. Hallyn | b0e7759 | 2011-03-23 16:43:24 -0700 | [diff] [blame] | 472 | int ipcperms(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp, short flag) |
| 473 | { |
Eric W. Biederman | 1efdb69 | 2012-02-07 16:54:11 -0800 | [diff] [blame] | 474 | kuid_t euid = current_euid(); |
Al Viro | a33e675 | 2008-12-10 03:40:06 -0500 | [diff] [blame] | 475 | int requested_mode, granted_mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 476 | |
Al Viro | a33e675 | 2008-12-10 03:40:06 -0500 | [diff] [blame] | 477 | audit_ipc_obj(ipcp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 478 | requested_mode = (flag >> 6) | (flag >> 3) | flag; |
| 479 | granted_mode = ipcp->mode; |
Eric W. Biederman | 1efdb69 | 2012-02-07 16:54:11 -0800 | [diff] [blame] | 480 | if (uid_eq(euid, ipcp->cuid) || |
| 481 | uid_eq(euid, ipcp->uid)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 482 | granted_mode >>= 6; |
| 483 | else if (in_group_p(ipcp->cgid) || in_group_p(ipcp->gid)) |
| 484 | granted_mode >>= 3; |
| 485 | /* is there some bit set in requested_mode but not in granted_mode? */ |
Paul McQuade | 46c0a8c | 2014-06-06 14:37:37 -0700 | [diff] [blame] | 486 | if ((requested_mode & ~granted_mode & 0007) && |
Serge E. Hallyn | b0e7759 | 2011-03-23 16:43:24 -0700 | [diff] [blame] | 487 | !ns_capable(ns->user_ns, CAP_IPC_OWNER)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 488 | return -1; |
| 489 | |
| 490 | return security_ipc_permission(ipcp, flag); |
| 491 | } |
| 492 | |
| 493 | /* |
| 494 | * Functions to convert between the kern_ipc_perm structure and the |
| 495 | * old/new ipc_perm structures |
| 496 | */ |
| 497 | |
| 498 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 499 | * kernel_to_ipc64_perm - convert kernel ipc permissions to user |
| 500 | * @in: kernel permissions |
| 501 | * @out: new style ipc permissions |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 502 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 503 | * Turn the kernel object @in into a set of permissions descriptions |
| 504 | * for returning to userspace (@out). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 505 | */ |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 506 | void kernel_to_ipc64_perm(struct kern_ipc_perm *in, struct ipc64_perm *out) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 507 | { |
| 508 | out->key = in->key; |
Eric W. Biederman | 1efdb69 | 2012-02-07 16:54:11 -0800 | [diff] [blame] | 509 | out->uid = from_kuid_munged(current_user_ns(), in->uid); |
| 510 | out->gid = from_kgid_munged(current_user_ns(), in->gid); |
| 511 | out->cuid = from_kuid_munged(current_user_ns(), in->cuid); |
| 512 | out->cgid = from_kgid_munged(current_user_ns(), in->cgid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 513 | out->mode = in->mode; |
| 514 | out->seq = in->seq; |
| 515 | } |
| 516 | |
| 517 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 518 | * ipc64_perm_to_ipc_perm - convert new ipc permissions to old |
| 519 | * @in: new style ipc permissions |
| 520 | * @out: old style ipc permissions |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 521 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 522 | * Turn the new style permissions object @in into a compatibility |
| 523 | * object and store it into the @out pointer. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 524 | */ |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 525 | void ipc64_perm_to_ipc_perm(struct ipc64_perm *in, struct ipc_perm *out) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 526 | { |
| 527 | out->key = in->key; |
| 528 | SET_UID(out->uid, in->uid); |
| 529 | SET_GID(out->gid, in->gid); |
| 530 | SET_UID(out->cuid, in->cuid); |
| 531 | SET_GID(out->cgid, in->cgid); |
| 532 | out->mode = in->mode; |
| 533 | out->seq = in->seq; |
| 534 | } |
| 535 | |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 536 | /** |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 537 | * ipc_obtain_object_idr |
Davidlohr Bueso | 4d2bff5 | 2013-04-30 19:15:19 -0700 | [diff] [blame] | 538 | * @ids: ipc identifier set |
| 539 | * @id: ipc id to look for |
| 540 | * |
| 541 | * Look for an id in the ipc ids idr and return associated ipc object. |
| 542 | * |
| 543 | * Call inside the RCU critical section. |
| 544 | * The ipc object is *not* locked on exit. |
| 545 | */ |
Davidlohr Bueso | 55b7ae5 | 2015-06-30 14:58:42 -0700 | [diff] [blame] | 546 | struct kern_ipc_perm *ipc_obtain_object_idr(struct ipc_ids *ids, int id) |
Davidlohr Bueso | 4d2bff5 | 2013-04-30 19:15:19 -0700 | [diff] [blame] | 547 | { |
| 548 | struct kern_ipc_perm *out; |
| 549 | int lid = ipcid_to_idx(id); |
| 550 | |
Guillaume Knispel | 0cfb6ae | 2017-09-08 16:17:55 -0700 | [diff] [blame] | 551 | if (unlikely(!ids->tables_initialized)) |
| 552 | return ERR_PTR(-EINVAL); |
| 553 | |
Davidlohr Bueso | 4d2bff5 | 2013-04-30 19:15:19 -0700 | [diff] [blame] | 554 | out = idr_find(&ids->ipcs_idr, lid); |
| 555 | if (!out) |
| 556 | return ERR_PTR(-EINVAL); |
| 557 | |
| 558 | return out; |
| 559 | } |
| 560 | |
| 561 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 562 | * ipc_lock - lock an ipc structure without rwsem held |
| 563 | * @ids: ipc identifier set |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 564 | * @id: ipc id to look for |
| 565 | * |
| 566 | * Look for an id in the ipc ids idr and lock the associated ipc object. |
| 567 | * |
Davidlohr Bueso | 4d2bff5 | 2013-04-30 19:15:19 -0700 | [diff] [blame] | 568 | * The ipc object is locked on successful exit. |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 569 | */ |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 570 | struct kern_ipc_perm *ipc_lock(struct ipc_ids *ids, int id) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 571 | { |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 572 | struct kern_ipc_perm *out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 573 | |
| 574 | rcu_read_lock(); |
Davidlohr Bueso | 55b7ae5 | 2015-06-30 14:58:42 -0700 | [diff] [blame] | 575 | out = ipc_obtain_object_idr(ids, id); |
Davidlohr Bueso | 4d2bff5 | 2013-04-30 19:15:19 -0700 | [diff] [blame] | 576 | if (IS_ERR(out)) |
Davidlohr Bueso | f8b5918 | 2015-06-30 14:58:45 -0700 | [diff] [blame] | 577 | goto err; |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 578 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 579 | spin_lock(&out->lock); |
Davidlohr Bueso | 4d2bff5 | 2013-04-30 19:15:19 -0700 | [diff] [blame] | 580 | |
Davidlohr Bueso | f8b5918 | 2015-06-30 14:58:45 -0700 | [diff] [blame] | 581 | /* |
| 582 | * ipc_rmid() may have already freed the ID while ipc_lock() |
| 583 | * was spinning: here verify that the structure is still valid. |
| 584 | * Upon races with RMID, return -EIDRM, thus indicating that |
| 585 | * the ID points to a removed identifier. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 586 | */ |
Rafael Aquini | 72a8ff2 | 2014-01-27 17:07:02 -0800 | [diff] [blame] | 587 | if (ipc_valid_object(out)) |
Davidlohr Bueso | 4d2bff5 | 2013-04-30 19:15:19 -0700 | [diff] [blame] | 588 | return out; |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 589 | |
Davidlohr Bueso | 4d2bff5 | 2013-04-30 19:15:19 -0700 | [diff] [blame] | 590 | spin_unlock(&out->lock); |
Davidlohr Bueso | f8b5918 | 2015-06-30 14:58:45 -0700 | [diff] [blame] | 591 | out = ERR_PTR(-EIDRM); |
| 592 | err: |
Davidlohr Bueso | 4d2bff5 | 2013-04-30 19:15:19 -0700 | [diff] [blame] | 593 | rcu_read_unlock(); |
| 594 | return out; |
| 595 | } |
| 596 | |
| 597 | /** |
| 598 | * ipc_obtain_object_check |
| 599 | * @ids: ipc identifier set |
| 600 | * @id: ipc id to look for |
| 601 | * |
Davidlohr Bueso | 55b7ae5 | 2015-06-30 14:58:42 -0700 | [diff] [blame] | 602 | * Similar to ipc_obtain_object_idr() but also checks |
Davidlohr Bueso | 4d2bff5 | 2013-04-30 19:15:19 -0700 | [diff] [blame] | 603 | * the ipc object reference counter. |
| 604 | * |
| 605 | * Call inside the RCU critical section. |
| 606 | * The ipc object is *not* locked on exit. |
| 607 | */ |
| 608 | struct kern_ipc_perm *ipc_obtain_object_check(struct ipc_ids *ids, int id) |
| 609 | { |
Davidlohr Bueso | 55b7ae5 | 2015-06-30 14:58:42 -0700 | [diff] [blame] | 610 | struct kern_ipc_perm *out = ipc_obtain_object_idr(ids, id); |
Davidlohr Bueso | 4d2bff5 | 2013-04-30 19:15:19 -0700 | [diff] [blame] | 611 | |
| 612 | if (IS_ERR(out)) |
| 613 | goto out; |
| 614 | |
| 615 | if (ipc_checkid(out, id)) |
Davidlohr Bueso | 6157dbb | 2015-06-30 14:58:48 -0700 | [diff] [blame] | 616 | return ERR_PTR(-EINVAL); |
Davidlohr Bueso | 4d2bff5 | 2013-04-30 19:15:19 -0700 | [diff] [blame] | 617 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 618 | return out; |
| 619 | } |
| 620 | |
Pavel Emelyanov | b2d75cd | 2008-02-08 04:18:54 -0800 | [diff] [blame] | 621 | /** |
| 622 | * ipcget - Common sys_*get() code |
Masanari Iida | da3dae5 | 2014-09-09 01:27:23 +0900 | [diff] [blame] | 623 | * @ns: namespace |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 624 | * @ids: ipc identifier set |
| 625 | * @ops: operations to be called on ipc object creation, permission checks |
| 626 | * and further checks |
| 627 | * @params: the parameters needed by the previous operations. |
Pavel Emelyanov | b2d75cd | 2008-02-08 04:18:54 -0800 | [diff] [blame] | 628 | * |
| 629 | * Common routine called by sys_msgget(), sys_semget() and sys_shmget(). |
| 630 | */ |
| 631 | int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids, |
Mathias Krause | eb66ec4 | 2014-06-06 14:37:36 -0700 | [diff] [blame] | 632 | const struct ipc_ops *ops, struct ipc_params *params) |
Pavel Emelyanov | b2d75cd | 2008-02-08 04:18:54 -0800 | [diff] [blame] | 633 | { |
| 634 | if (params->key == IPC_PRIVATE) |
| 635 | return ipcget_new(ns, ids, ops, params); |
| 636 | else |
| 637 | return ipcget_public(ns, ids, ops, params); |
| 638 | } |
| 639 | |
Pierre Peiffer | 8f4a380 | 2008-04-29 01:00:51 -0700 | [diff] [blame] | 640 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 641 | * ipc_update_perm - update the permissions of an ipc object |
Pierre Peiffer | 8f4a380 | 2008-04-29 01:00:51 -0700 | [diff] [blame] | 642 | * @in: the permission given as input. |
| 643 | * @out: the permission of the ipc to set. |
| 644 | */ |
Eric W. Biederman | 1efdb69 | 2012-02-07 16:54:11 -0800 | [diff] [blame] | 645 | int ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out) |
Pierre Peiffer | 8f4a380 | 2008-04-29 01:00:51 -0700 | [diff] [blame] | 646 | { |
Eric W. Biederman | 1efdb69 | 2012-02-07 16:54:11 -0800 | [diff] [blame] | 647 | kuid_t uid = make_kuid(current_user_ns(), in->uid); |
| 648 | kgid_t gid = make_kgid(current_user_ns(), in->gid); |
| 649 | if (!uid_valid(uid) || !gid_valid(gid)) |
| 650 | return -EINVAL; |
| 651 | |
| 652 | out->uid = uid; |
| 653 | out->gid = gid; |
Pierre Peiffer | 8f4a380 | 2008-04-29 01:00:51 -0700 | [diff] [blame] | 654 | out->mode = (out->mode & ~S_IRWXUGO) |
| 655 | | (in->mode & S_IRWXUGO); |
Eric W. Biederman | 1efdb69 | 2012-02-07 16:54:11 -0800 | [diff] [blame] | 656 | |
| 657 | return 0; |
Pierre Peiffer | 8f4a380 | 2008-04-29 01:00:51 -0700 | [diff] [blame] | 658 | } |
| 659 | |
Pierre Peiffer | a5f75e7 | 2008-04-29 01:00:54 -0700 | [diff] [blame] | 660 | /** |
Davidlohr Bueso | 3b1c4ad | 2013-09-11 14:26:17 -0700 | [diff] [blame] | 661 | * ipcctl_pre_down_nolock - retrieve an ipc and check permissions for some IPC_XXX cmd |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 662 | * @ns: ipc namespace |
Pierre Peiffer | a5f75e7 | 2008-04-29 01:00:54 -0700 | [diff] [blame] | 663 | * @ids: the table of ids where to look for the ipc |
| 664 | * @id: the id of the ipc to retrieve |
| 665 | * @cmd: the cmd to check |
| 666 | * @perm: the permission to set |
| 667 | * @extra_perm: one extra permission parameter used by msq |
| 668 | * |
| 669 | * This function does some common audit and permissions check for some IPC_XXX |
| 670 | * cmd and is called from semctl_down, shmctl_down and msgctl_down. |
mchehab@s-opensource.com | 0e056eb | 2017-03-30 17:11:36 -0300 | [diff] [blame] | 671 | * It must be called without any lock held and: |
| 672 | * |
| 673 | * - retrieves the ipc with the given id in the given table. |
| 674 | * - performs some audit and permission check, depending on the given cmd |
| 675 | * - returns a pointer to the ipc object or otherwise, the corresponding |
| 676 | * error. |
Davidlohr Bueso | 7b4cc5d | 2013-07-08 16:01:12 -0700 | [diff] [blame] | 677 | * |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 678 | * Call holding the both the rwsem and the rcu read lock. |
Pierre Peiffer | a5f75e7 | 2008-04-29 01:00:54 -0700 | [diff] [blame] | 679 | */ |
Davidlohr Bueso | 444d0f6 | 2013-04-30 19:15:24 -0700 | [diff] [blame] | 680 | struct kern_ipc_perm *ipcctl_pre_down_nolock(struct ipc_namespace *ns, |
Davidlohr Bueso | 3b1c4ad | 2013-09-11 14:26:17 -0700 | [diff] [blame] | 681 | struct ipc_ids *ids, int id, int cmd, |
| 682 | struct ipc64_perm *perm, int extra_perm) |
Davidlohr Bueso | 444d0f6 | 2013-04-30 19:15:24 -0700 | [diff] [blame] | 683 | { |
Eric W. Biederman | 1efdb69 | 2012-02-07 16:54:11 -0800 | [diff] [blame] | 684 | kuid_t euid; |
Davidlohr Bueso | 444d0f6 | 2013-04-30 19:15:24 -0700 | [diff] [blame] | 685 | int err = -EPERM; |
| 686 | struct kern_ipc_perm *ipcp; |
Pierre Peiffer | a5f75e7 | 2008-04-29 01:00:54 -0700 | [diff] [blame] | 687 | |
Davidlohr Bueso | 444d0f6 | 2013-04-30 19:15:24 -0700 | [diff] [blame] | 688 | ipcp = ipc_obtain_object_check(ids, id); |
Pierre Peiffer | a5f75e7 | 2008-04-29 01:00:54 -0700 | [diff] [blame] | 689 | if (IS_ERR(ipcp)) { |
| 690 | err = PTR_ERR(ipcp); |
Davidlohr Bueso | 7b4cc5d | 2013-07-08 16:01:12 -0700 | [diff] [blame] | 691 | goto err; |
Pierre Peiffer | a5f75e7 | 2008-04-29 01:00:54 -0700 | [diff] [blame] | 692 | } |
| 693 | |
Al Viro | a33e675 | 2008-12-10 03:40:06 -0500 | [diff] [blame] | 694 | audit_ipc_obj(ipcp); |
Al Viro | e816f37 | 2008-12-10 03:47:15 -0500 | [diff] [blame] | 695 | if (cmd == IPC_SET) |
| 696 | audit_ipc_set_perm(extra_perm, perm->uid, |
Davidlohr Bueso | 444d0f6 | 2013-04-30 19:15:24 -0700 | [diff] [blame] | 697 | perm->gid, perm->mode); |
David Howells | 414c070 | 2008-11-14 10:39:06 +1100 | [diff] [blame] | 698 | |
| 699 | euid = current_euid(); |
Eric W. Biederman | 1efdb69 | 2012-02-07 16:54:11 -0800 | [diff] [blame] | 700 | if (uid_eq(euid, ipcp->cuid) || uid_eq(euid, ipcp->uid) || |
Serge E. Hallyn | b0e7759 | 2011-03-23 16:43:24 -0700 | [diff] [blame] | 701 | ns_capable(ns->user_ns, CAP_SYS_ADMIN)) |
Davidlohr Bueso | 7b4cc5d | 2013-07-08 16:01:12 -0700 | [diff] [blame] | 702 | return ipcp; /* successful lookup */ |
| 703 | err: |
Pierre Peiffer | a5f75e7 | 2008-04-29 01:00:54 -0700 | [diff] [blame] | 704 | return ERR_PTR(err); |
| 705 | } |
| 706 | |
Will Deacon | c1d7e01 | 2012-07-30 14:42:46 -0700 | [diff] [blame] | 707 | #ifdef CONFIG_ARCH_WANT_IPC_PARSE_VERSION |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 708 | |
| 709 | |
| 710 | /** |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 711 | * ipc_parse_version - ipc call version |
| 712 | * @cmd: pointer to command |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | * |
Davidlohr Bueso | 8001c85 | 2014-01-27 17:07:05 -0800 | [diff] [blame] | 714 | * Return IPC_64 for new style IPC and IPC_OLD for old style IPC. |
| 715 | * The @cmd value is turned from an encoding command and version into |
| 716 | * just the command code. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 717 | */ |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 718 | int ipc_parse_version(int *cmd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 719 | { |
| 720 | if (*cmd & IPC_64) { |
| 721 | *cmd ^= IPC_64; |
| 722 | return IPC_64; |
| 723 | } else { |
| 724 | return IPC_OLD; |
| 725 | } |
| 726 | } |
| 727 | |
Will Deacon | c1d7e01 | 2012-07-30 14:42:46 -0700 | [diff] [blame] | 728 | #endif /* CONFIG_ARCH_WANT_IPC_PARSE_VERSION */ |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 729 | |
| 730 | #ifdef CONFIG_PROC_FS |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 731 | struct ipc_proc_iter { |
| 732 | struct ipc_namespace *ns; |
| 733 | struct ipc_proc_iface *iface; |
| 734 | }; |
| 735 | |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 736 | /* |
| 737 | * This routine locks the ipc structure found at least at position pos. |
| 738 | */ |
Adrian Bunk | b524b9a | 2008-02-06 01:36:28 -0800 | [diff] [blame] | 739 | static struct kern_ipc_perm *sysvipc_find_ipc(struct ipc_ids *ids, loff_t pos, |
| 740 | loff_t *new_pos) |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 741 | { |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 742 | struct kern_ipc_perm *ipc; |
| 743 | int total, id; |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 744 | |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 745 | total = 0; |
| 746 | for (id = 0; id < pos && total < ids->in_use; id++) { |
| 747 | ipc = idr_find(&ids->ipcs_idr, id); |
| 748 | if (ipc != NULL) |
| 749 | total++; |
| 750 | } |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 751 | |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 752 | if (total >= ids->in_use) |
| 753 | return NULL; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 754 | |
Manfred Spraul | 239521f | 2014-01-27 17:07:04 -0800 | [diff] [blame] | 755 | for (; pos < IPCMNI; pos++) { |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 756 | ipc = idr_find(&ids->ipcs_idr, pos); |
| 757 | if (ipc != NULL) { |
| 758 | *new_pos = pos + 1; |
Davidlohr Bueso | 32a2750 | 2013-09-11 14:26:29 -0700 | [diff] [blame] | 759 | rcu_read_lock(); |
| 760 | ipc_lock_object(ipc); |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 761 | return ipc; |
| 762 | } |
| 763 | } |
| 764 | |
| 765 | /* Out of range - return NULL to terminate iteration */ |
| 766 | return NULL; |
| 767 | } |
| 768 | |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 769 | static void *sysvipc_proc_next(struct seq_file *s, void *it, loff_t *pos) |
| 770 | { |
| 771 | struct ipc_proc_iter *iter = s->private; |
| 772 | struct ipc_proc_iface *iface = iter->iface; |
| 773 | struct kern_ipc_perm *ipc = it; |
| 774 | |
| 775 | /* If we had an ipc id locked before, unlock it */ |
| 776 | if (ipc && ipc != SEQ_START_TOKEN) |
| 777 | ipc_unlock(ipc); |
| 778 | |
Pierre Peiffer | ed2ddbf | 2008-02-08 04:18:57 -0800 | [diff] [blame] | 779 | return sysvipc_find_ipc(&iter->ns->ids[iface->ids], *pos, pos); |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 780 | } |
| 781 | |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 782 | /* |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 783 | * File positions: pos 0 -> header, pos n -> ipc id = n - 1. |
| 784 | * SeqFile iterator: iterator value locked ipc pointer or SEQ_TOKEN_START. |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 785 | */ |
| 786 | static void *sysvipc_proc_start(struct seq_file *s, loff_t *pos) |
| 787 | { |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 788 | struct ipc_proc_iter *iter = s->private; |
| 789 | struct ipc_proc_iface *iface = iter->iface; |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 790 | struct ipc_ids *ids; |
| 791 | |
Pierre Peiffer | ed2ddbf | 2008-02-08 04:18:57 -0800 | [diff] [blame] | 792 | ids = &iter->ns->ids[iface->ids]; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 793 | |
| 794 | /* |
| 795 | * Take the lock - this will be released by the corresponding |
| 796 | * call to stop(). |
| 797 | */ |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 798 | down_read(&ids->rwsem); |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 799 | |
| 800 | /* pos < 0 is invalid */ |
| 801 | if (*pos < 0) |
| 802 | return NULL; |
| 803 | |
| 804 | /* pos == 0 means header */ |
| 805 | if (*pos == 0) |
| 806 | return SEQ_START_TOKEN; |
| 807 | |
| 808 | /* Find the (pos-1)th ipc */ |
Nadia Derbey | 7ca7e56 | 2007-10-18 23:40:48 -0700 | [diff] [blame] | 809 | return sysvipc_find_ipc(ids, *pos - 1, pos); |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 810 | } |
| 811 | |
| 812 | static void sysvipc_proc_stop(struct seq_file *s, void *it) |
| 813 | { |
| 814 | struct kern_ipc_perm *ipc = it; |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 815 | struct ipc_proc_iter *iter = s->private; |
| 816 | struct ipc_proc_iface *iface = iter->iface; |
Kirill Korotaev | 73ea413 | 2006-10-02 02:18:20 -0700 | [diff] [blame] | 817 | struct ipc_ids *ids; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 818 | |
Nadia Derbey | f4566f0 | 2007-10-18 23:40:53 -0700 | [diff] [blame] | 819 | /* If we had a locked structure, release it */ |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 820 | if (ipc && ipc != SEQ_START_TOKEN) |
| 821 | ipc_unlock(ipc); |
| 822 | |
Pierre Peiffer | ed2ddbf | 2008-02-08 04:18:57 -0800 | [diff] [blame] | 823 | ids = &iter->ns->ids[iface->ids]; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 824 | /* Release the lock we took in start() */ |
Davidlohr Bueso | d9a605e | 2013-09-11 14:26:24 -0700 | [diff] [blame] | 825 | up_read(&ids->rwsem); |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 826 | } |
| 827 | |
| 828 | static int sysvipc_proc_show(struct seq_file *s, void *it) |
| 829 | { |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 830 | struct ipc_proc_iter *iter = s->private; |
| 831 | struct ipc_proc_iface *iface = iter->iface; |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 832 | |
Joe Perches | 7f032d6 | 2015-04-15 16:17:54 -0700 | [diff] [blame] | 833 | if (it == SEQ_START_TOKEN) { |
| 834 | seq_puts(s, iface->header); |
| 835 | return 0; |
| 836 | } |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 837 | |
| 838 | return iface->show(s, it); |
| 839 | } |
| 840 | |
James Morris | 88e9d34 | 2009-09-22 16:43:43 -0700 | [diff] [blame] | 841 | static const struct seq_operations sysvipc_proc_seqops = { |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 842 | .start = sysvipc_proc_start, |
| 843 | .stop = sysvipc_proc_stop, |
| 844 | .next = sysvipc_proc_next, |
| 845 | .show = sysvipc_proc_show, |
| 846 | }; |
| 847 | |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 848 | static int sysvipc_proc_open(struct inode *inode, struct file *file) |
| 849 | { |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 850 | struct ipc_proc_iter *iter; |
| 851 | |
Rob Jones | d66a052 | 2014-10-13 15:54:14 -0700 | [diff] [blame] | 852 | iter = __seq_open_private(file, &sysvipc_proc_seqops, sizeof(*iter)); |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 853 | if (!iter) |
Rob Jones | d66a052 | 2014-10-13 15:54:14 -0700 | [diff] [blame] | 854 | return -ENOMEM; |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 855 | |
Al Viro | d9dda78 | 2013-03-31 18:16:14 -0400 | [diff] [blame] | 856 | iter->iface = PDE_DATA(inode); |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 857 | iter->ns = get_ipc_ns(current->nsproxy->ipc_ns); |
Rob Jones | d66a052 | 2014-10-13 15:54:14 -0700 | [diff] [blame] | 858 | |
| 859 | return 0; |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 860 | } |
| 861 | |
| 862 | static int sysvipc_proc_release(struct inode *inode, struct file *file) |
| 863 | { |
| 864 | struct seq_file *seq = file->private_data; |
| 865 | struct ipc_proc_iter *iter = seq->private; |
| 866 | put_ipc_ns(iter->ns); |
| 867 | return seq_release_private(inode, file); |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 868 | } |
| 869 | |
Arjan van de Ven | 9a32144 | 2007-02-12 00:55:35 -0800 | [diff] [blame] | 870 | static const struct file_operations sysvipc_proc_fops = { |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 871 | .open = sysvipc_proc_open, |
| 872 | .read = seq_read, |
| 873 | .llseek = seq_lseek, |
Eric W. Biederman | bc1fc6d | 2007-02-12 00:52:10 -0800 | [diff] [blame] | 874 | .release = sysvipc_proc_release, |
Mike Waychison | ae78177 | 2005-09-06 15:17:09 -0700 | [diff] [blame] | 875 | }; |
| 876 | #endif /* CONFIG_PROC_FS */ |