Merge tag 'fuse-update-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi...
[platform/kernel/linux-rpi.git] / ipc / mq_sysctl.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Copyright (C) 2007 IBM Corporation
4  *
5  *  Author: Cedric Le Goater <clg@fr.ibm.com>
6  */
7
8 #include <linux/nsproxy.h>
9 #include <linux/ipc_namespace.h>
10 #include <linux/sysctl.h>
11
12 #include <linux/stat.h>
13 #include <linux/capability.h>
14 #include <linux/slab.h>
15
16 static int msg_max_limit_min = MIN_MSGMAX;
17 static int msg_max_limit_max = HARD_MSGMAX;
18
19 static int msg_maxsize_limit_min = MIN_MSGSIZEMAX;
20 static int msg_maxsize_limit_max = HARD_MSGSIZEMAX;
21
22 static struct ctl_table mq_sysctls[] = {
23         {
24                 .procname       = "queues_max",
25                 .data           = &init_ipc_ns.mq_queues_max,
26                 .maxlen         = sizeof(int),
27                 .mode           = 0644,
28                 .proc_handler   = proc_dointvec,
29         },
30         {
31                 .procname       = "msg_max",
32                 .data           = &init_ipc_ns.mq_msg_max,
33                 .maxlen         = sizeof(int),
34                 .mode           = 0644,
35                 .proc_handler   = proc_dointvec_minmax,
36                 .extra1         = &msg_max_limit_min,
37                 .extra2         = &msg_max_limit_max,
38         },
39         {
40                 .procname       = "msgsize_max",
41                 .data           = &init_ipc_ns.mq_msgsize_max,
42                 .maxlen         = sizeof(int),
43                 .mode           = 0644,
44                 .proc_handler   = proc_dointvec_minmax,
45                 .extra1         = &msg_maxsize_limit_min,
46                 .extra2         = &msg_maxsize_limit_max,
47         },
48         {
49                 .procname       = "msg_default",
50                 .data           = &init_ipc_ns.mq_msg_default,
51                 .maxlen         = sizeof(int),
52                 .mode           = 0644,
53                 .proc_handler   = proc_dointvec_minmax,
54                 .extra1         = &msg_max_limit_min,
55                 .extra2         = &msg_max_limit_max,
56         },
57         {
58                 .procname       = "msgsize_default",
59                 .data           = &init_ipc_ns.mq_msgsize_default,
60                 .maxlen         = sizeof(int),
61                 .mode           = 0644,
62                 .proc_handler   = proc_dointvec_minmax,
63                 .extra1         = &msg_maxsize_limit_min,
64                 .extra2         = &msg_maxsize_limit_max,
65         },
66         {}
67 };
68
69 static struct ctl_table_set *set_lookup(struct ctl_table_root *root)
70 {
71         return &current->nsproxy->ipc_ns->mq_set;
72 }
73
74 static int set_is_seen(struct ctl_table_set *set)
75 {
76         return &current->nsproxy->ipc_ns->mq_set == set;
77 }
78
79 static struct ctl_table_root set_root = {
80         .lookup = set_lookup,
81 };
82
83 bool setup_mq_sysctls(struct ipc_namespace *ns)
84 {
85         struct ctl_table *tbl;
86
87         setup_sysctl_set(&ns->mq_set, &set_root, set_is_seen);
88
89         tbl = kmemdup(mq_sysctls, sizeof(mq_sysctls), GFP_KERNEL);
90         if (tbl) {
91                 int i;
92
93                 for (i = 0; i < ARRAY_SIZE(mq_sysctls); i++) {
94                         if (tbl[i].data == &init_ipc_ns.mq_queues_max)
95                                 tbl[i].data = &ns->mq_queues_max;
96
97                         else if (tbl[i].data == &init_ipc_ns.mq_msg_max)
98                                 tbl[i].data = &ns->mq_msg_max;
99
100                         else if (tbl[i].data == &init_ipc_ns.mq_msgsize_max)
101                                 tbl[i].data = &ns->mq_msgsize_max;
102
103                         else if (tbl[i].data == &init_ipc_ns.mq_msg_default)
104                                 tbl[i].data = &ns->mq_msg_default;
105
106                         else if (tbl[i].data == &init_ipc_ns.mq_msgsize_default)
107                                 tbl[i].data = &ns->mq_msgsize_default;
108                         else
109                                 tbl[i].data = NULL;
110                 }
111
112                 ns->mq_sysctls = __register_sysctl_table(&ns->mq_set,
113                                                          "fs/mqueue", tbl,
114                                                          ARRAY_SIZE(mq_sysctls));
115         }
116         if (!ns->mq_sysctls) {
117                 kfree(tbl);
118                 retire_sysctl_set(&ns->mq_set);
119                 return false;
120         }
121
122         return true;
123 }
124
125 void retire_mq_sysctls(struct ipc_namespace *ns)
126 {
127         struct ctl_table *tbl;
128
129         tbl = ns->mq_sysctls->ctl_table_arg;
130         unregister_sysctl_table(ns->mq_sysctls);
131         retire_sysctl_set(&ns->mq_set);
132         kfree(tbl);
133 }