1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2011 Bryan Schumaker <bjschuma@netapp.com>
4 *
5 * Uses debugfs to create fault injection points for client testing
6 */
7
8 #include <linux/types.h>
9 #include <linux/fs.h>
10 #include <linux/debugfs.h>
11 #include <linux/module.h>
12 #include <linux/nsproxy.h>
13 #include <linux/sunrpc/addr.h>
14 #include <linux/uaccess.h>
15 #include <linux/kernel.h>
16
17 #include "state.h"
18 #include "netns.h"
19
20 struct nfsd_fault_inject_op {
21 char *file;
22 u64 (*get)(void);
23 u64 (*set_val)(u64);
24 u64 (*set_clnt)(struct sockaddr_storage *, size_t);
25 };
26
27 static struct dentry *debug_dir;
28
fault_inject_read(struct file * file,char __user * buf,size_t len,loff_t * ppos)29 static ssize_t fault_inject_read(struct file *file, char __user *buf,
30 size_t len, loff_t *ppos)
31 {
32 static u64 val;
33 char read_buf[25];
34 size_t size;
35 loff_t pos = *ppos;
36 struct nfsd_fault_inject_op *op = file_inode(file)->i_private;
37
38 if (!pos)
39 val = op->get();
40 size = scnprintf(read_buf, sizeof(read_buf), "%llu\n", val);
41
42 return simple_read_from_buffer(buf, len, ppos, read_buf, size);
43 }
44
fault_inject_write(struct file * file,const char __user * buf,size_t len,loff_t * ppos)45 static ssize_t fault_inject_write(struct file *file, const char __user *buf,
46 size_t len, loff_t *ppos)
47 {
48 char write_buf[INET6_ADDRSTRLEN];
49 size_t size = min(sizeof(write_buf) - 1, len);
50 struct net *net = current->nsproxy->net_ns;
51 struct sockaddr_storage sa;
52 struct nfsd_fault_inject_op *op = file_inode(file)->i_private;
53 u64 val;
54 char *nl;
55
56 if (copy_from_user(write_buf, buf, size))
57 return -EFAULT;
58 write_buf[size] = '\0';
59
60 /* Deal with any embedded newlines in the string */
61 nl = strchr(write_buf, '\n');
62 if (nl) {
63 size = nl - write_buf;
64 *nl = '\0';
65 }
66
67 size = rpc_pton(net, write_buf, size, (struct sockaddr *)&sa, sizeof(sa));
68 if (size > 0) {
69 val = op->set_clnt(&sa, size);
70 if (val)
71 pr_info("NFSD [%s]: Client %s had %llu state object(s)\n",
72 op->file, write_buf, val);
73 } else {
74 val = simple_strtoll(write_buf, NULL, 0);
75 if (val == 0)
76 pr_info("NFSD Fault Injection: %s (all)", op->file);
77 else
78 pr_info("NFSD Fault Injection: %s (n = %llu)",
79 op->file, val);
80 val = op->set_val(val);
81 pr_info("NFSD: %s: found %llu", op->file, val);
82 }
83 return len; /* on success, claim we got the whole input */
84 }
85
86 static const struct file_operations fops_nfsd = {
87 .owner = THIS_MODULE,
88 .read = fault_inject_read,
89 .write = fault_inject_write,
90 };
91
nfsd_fault_inject_cleanup(void)92 void nfsd_fault_inject_cleanup(void)
93 {
94 debugfs_remove_recursive(debug_dir);
95 }
96
97 static struct nfsd_fault_inject_op inject_ops[] = {
98 {
99 .file = "forget_clients",
100 .get = nfsd_inject_print_clients,
101 .set_val = nfsd_inject_forget_clients,
102 .set_clnt = nfsd_inject_forget_client,
103 },
104 {
105 .file = "forget_locks",
106 .get = nfsd_inject_print_locks,
107 .set_val = nfsd_inject_forget_locks,
108 .set_clnt = nfsd_inject_forget_client_locks,
109 },
110 {
111 .file = "forget_openowners",
112 .get = nfsd_inject_print_openowners,
113 .set_val = nfsd_inject_forget_openowners,
114 .set_clnt = nfsd_inject_forget_client_openowners,
115 },
116 {
117 .file = "forget_delegations",
118 .get = nfsd_inject_print_delegations,
119 .set_val = nfsd_inject_forget_delegations,
120 .set_clnt = nfsd_inject_forget_client_delegations,
121 },
122 {
123 .file = "recall_delegations",
124 .get = nfsd_inject_print_delegations,
125 .set_val = nfsd_inject_recall_delegations,
126 .set_clnt = nfsd_inject_recall_client_delegations,
127 },
128 };
129
nfsd_fault_inject_init(void)130 void nfsd_fault_inject_init(void)
131 {
132 unsigned int i;
133 struct nfsd_fault_inject_op *op;
134 umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
135
136 debug_dir = debugfs_create_dir("nfsd", NULL);
137
138 for (i = 0; i < ARRAY_SIZE(inject_ops); i++) {
139 op = &inject_ops[i];
140 debugfs_create_file(op->file, mode, debug_dir, op, &fops_nfsd);
141 }
142 }
143