Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
afa588b2 EB |
2 | #include <linux/stat.h> |
3 | #include <linux/sysctl.h> | |
c59d87c4 | 4 | #include "../fs/xfs/xfs_sysctl.h" |
afa588b2 EB |
5 | #include <linux/sunrpc/debug.h> |
6 | #include <linux/string.h> | |
afa588b2 EB |
7 | #include <linux/syscalls.h> |
8 | #include <linux/namei.h> | |
9 | #include <linux/mount.h> | |
10 | #include <linux/fs.h> | |
11 | #include <linux/nsproxy.h> | |
12 | #include <linux/pid_namespace.h> | |
13 | #include <linux/file.h> | |
14 | #include <linux/ctype.h> | |
63395b65 | 15 | #include <linux/netdevice.h> |
69e4469a | 16 | #include <linux/kernel.h> |
ede9c277 | 17 | #include <linux/uuid.h> |
5a0e3ad6 | 18 | #include <linux/slab.h> |
c5ddd202 | 19 | #include <linux/compat.h> |
afa588b2 | 20 | |
26a7034b EB |
21 | static ssize_t binary_sysctl(const int *name, int nlen, |
22 | void __user *oldval, size_t oldlen, void __user *newval, size_t newlen) | |
afa588b2 | 23 | { |
2830b683 | 24 | return -ENOSYS; |
afa588b2 EB |
25 | } |
26 | ||
2830b683 | 27 | static void deprecated_sysctl_warning(const int *name, int nlen) |
afa588b2 | 28 | { |
afa588b2 EB |
29 | int i; |
30 | ||
61cf6931 AK |
31 | /* |
32 | * CTL_KERN/KERN_VERSION is used by older glibc and cannot | |
33 | * ever go away. | |
34 | */ | |
9380fa60 | 35 | if (nlen >= 2 && name[0] == CTL_KERN && name[1] == KERN_VERSION) |
61cf6931 AK |
36 | return; |
37 | ||
2fb10732 | 38 | if (printk_ratelimit()) { |
afa588b2 EB |
39 | printk(KERN_INFO |
40 | "warning: process `%s' used the deprecated sysctl " | |
41 | "system call with ", current->comm); | |
2830b683 | 42 | for (i = 0; i < nlen; i++) |
7560ef39 TH |
43 | printk(KERN_CONT "%d.", name[i]); |
44 | printk(KERN_CONT "\n"); | |
afa588b2 | 45 | } |
2830b683 EB |
46 | return; |
47 | } | |
48 | ||
4440095c AK |
49 | #define WARN_ONCE_HASH_BITS 8 |
50 | #define WARN_ONCE_HASH_SIZE (1<<WARN_ONCE_HASH_BITS) | |
51 | ||
52 | static DECLARE_BITMAP(warn_once_bitmap, WARN_ONCE_HASH_SIZE); | |
53 | ||
54 | #define FNV32_OFFSET 2166136261U | |
55 | #define FNV32_PRIME 0x01000193 | |
56 | ||
57 | /* | |
58 | * Print each legacy sysctl (approximately) only once. | |
59 | * To avoid making the tables non-const use a external | |
60 | * hash-table instead. | |
61 | * Worst case hash collision: 6, but very rarely. | |
62 | * NOTE! We don't use the SMP-safe bit tests. We simply | |
63 | * don't care enough. | |
64 | */ | |
65 | static void warn_on_bintable(const int *name, int nlen) | |
66 | { | |
67 | int i; | |
68 | u32 hash = FNV32_OFFSET; | |
69 | ||
70 | for (i = 0; i < nlen; i++) | |
71 | hash = (hash ^ name[i]) * FNV32_PRIME; | |
72 | hash %= WARN_ONCE_HASH_SIZE; | |
73 | if (__test_and_set_bit(hash, warn_once_bitmap)) | |
74 | return; | |
75 | deprecated_sysctl_warning(name, nlen); | |
76 | } | |
77 | ||
26a7034b EB |
78 | static ssize_t do_sysctl(int __user *args_name, int nlen, |
79 | void __user *oldval, size_t oldlen, void __user *newval, size_t newlen) | |
2830b683 EB |
80 | { |
81 | int name[CTL_MAXNAME]; | |
2830b683 EB |
82 | int i; |
83 | ||
26a7034b EB |
84 | /* Check args->nlen. */ |
85 | if (nlen < 0 || nlen > CTL_MAXNAME) | |
2830b683 | 86 | return -ENOTDIR; |
2830b683 EB |
87 | /* Read in the sysctl name for simplicity */ |
88 | for (i = 0; i < nlen; i++) | |
89 | if (get_user(name[i], args_name + i)) | |
90 | return -EFAULT; | |
91 | ||
4440095c | 92 | warn_on_bintable(name, nlen); |
2830b683 | 93 | |
26a7034b | 94 | return binary_sysctl(name, nlen, oldval, oldlen, newval, newlen); |
2830b683 EB |
95 | } |
96 | ||
2830b683 EB |
97 | SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args) |
98 | { | |
99 | struct __sysctl_args tmp; | |
26a7034b EB |
100 | size_t oldlen = 0; |
101 | ssize_t result; | |
2830b683 EB |
102 | |
103 | if (copy_from_user(&tmp, args, sizeof(tmp))) | |
104 | return -EFAULT; | |
105 | ||
26a7034b EB |
106 | if (tmp.oldval && !tmp.oldlenp) |
107 | return -EFAULT; | |
108 | ||
109 | if (tmp.oldlenp && get_user(oldlen, tmp.oldlenp)) | |
110 | return -EFAULT; | |
111 | ||
112 | result = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, oldlen, | |
113 | tmp.newval, tmp.newlen); | |
114 | ||
115 | if (result >= 0) { | |
116 | oldlen = result; | |
117 | result = 0; | |
118 | } | |
2830b683 | 119 | |
26a7034b EB |
120 | if (tmp.oldlenp && put_user(oldlen, tmp.oldlenp)) |
121 | return -EFAULT; | |
122 | ||
123 | return result; | |
afa588b2 | 124 | } |
da3f6f9b | 125 | |
26a7034b | 126 | |
da3f6f9b | 127 | #ifdef CONFIG_COMPAT |
da3f6f9b EB |
128 | |
129 | struct compat_sysctl_args { | |
130 | compat_uptr_t name; | |
131 | int nlen; | |
132 | compat_uptr_t oldval; | |
133 | compat_uptr_t oldlenp; | |
134 | compat_uptr_t newval; | |
135 | compat_size_t newlen; | |
136 | compat_ulong_t __unused[4]; | |
137 | }; | |
138 | ||
c5ddd202 | 139 | COMPAT_SYSCALL_DEFINE1(sysctl, struct compat_sysctl_args __user *, args) |
da3f6f9b EB |
140 | { |
141 | struct compat_sysctl_args tmp; | |
142 | compat_size_t __user *compat_oldlenp; | |
da3f6f9b EB |
143 | size_t oldlen = 0; |
144 | ssize_t result; | |
145 | ||
146 | if (copy_from_user(&tmp, args, sizeof(tmp))) | |
147 | return -EFAULT; | |
148 | ||
26a7034b EB |
149 | if (tmp.oldval && !tmp.oldlenp) |
150 | return -EFAULT; | |
da3f6f9b | 151 | |
26a7034b EB |
152 | compat_oldlenp = compat_ptr(tmp.oldlenp); |
153 | if (compat_oldlenp && get_user(oldlen, compat_oldlenp)) | |
154 | return -EFAULT; | |
da3f6f9b | 155 | |
da3f6f9b | 156 | result = do_sysctl(compat_ptr(tmp.name), tmp.nlen, |
26a7034b | 157 | compat_ptr(tmp.oldval), oldlen, |
da3f6f9b | 158 | compat_ptr(tmp.newval), tmp.newlen); |
da3f6f9b | 159 | |
26a7034b EB |
160 | if (result >= 0) { |
161 | oldlen = result; | |
162 | result = 0; | |
da3f6f9b EB |
163 | } |
164 | ||
26a7034b EB |
165 | if (compat_oldlenp && put_user(oldlen, compat_oldlenp)) |
166 | return -EFAULT; | |
167 | ||
da3f6f9b EB |
168 | return result; |
169 | } | |
170 | ||
171 | #endif /* CONFIG_COMPAT */ |