| 1 | |
| 2 | |
| 3 | *
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| 4 | * Copyright (C) 2011 Novell Inc.
|
| 5 |
|
| 6 |
|
| 7 | #include <linux/fs.h>
|
| 8 | #include <linux/slab.h>
|
| 9 | #include <linux/namei.h>
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| 10 | #include <linux/file.h>
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| 11 | #include <linux/filelock.h>
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| 12 | #include <linux/xattr.h>
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| 13 | #include <linux/rbtree.h>
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| 14 | #include <linux/security.h>
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| 15 | #include <linux/cred.h>
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| 16 | #include <linux/ratelimit.h>
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| 17 | #include <linux/overflow.h>
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| 18 | #include "overlayfs.h"
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| 19 |
|
| 20 | struct ovl_cache_entry {
|
| 21 | unsigned int len;
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| 22 | unsigned int type;
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| 23 | u64 real_ino;
|
| 24 | u64 ino;
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| 25 | struct list_head l_node;
|
| 26 | struct rb_node node;
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| 27 | struct ovl_cache_entry *next_maybe_whiteout;
|
| 28 | bool is_upper;
|
| 29 | bool is_whiteout;
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| 30 | bool check_xwhiteout;
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| 31 | const char *c_name;
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| 32 | int c_len;
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| 33 | char name[];
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| 34 | };
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| 35 |
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| 36 | struct ovl_dir_cache {
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| 37 | long refcount;
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| 38 | u64 version;
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| 39 | struct list_head entries;
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| 40 | struct rb_root root;
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| 41 | };
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| 42 |
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| 43 | struct ovl_readdir_data {
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| 44 | struct dir_context ctx;
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| 45 | struct dentry *dentry;
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| 46 | bool is_lowest;
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| 47 | struct rb_root *root;
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| 48 | struct list_head *list;
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| 49 | struct list_head middle;
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| 50 | struct ovl_cache_entry *first_maybe_whiteout;
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| 51 | struct unicode_map *map;
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| 52 | int count;
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| 53 | int err;
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| 54 | bool is_upper;
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| 55 | bool d_type_supported;
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| 56 | bool in_xwhiteouts_dir;
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| 57 | };
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| 58 |
|
| 59 | struct ovl_dir_file {
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| 60 | bool is_real;
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| 61 | bool is_upper;
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| 62 | struct ovl_dir_cache *cache;
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| 63 | struct list_head *cursor;
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| 64 | struct file *realfile;
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| 65 | struct file *upperfile;
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| 66 | };
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| 67 |
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| 68 | static struct ovl_cache_entry *ovl_cache_entry_from_node(struct rb_node *n)
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| 69 | {
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| 70 | return rb_entry(n, struct ovl_cache_entry, node);
|
| 71 | }
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| 72 |
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| 73 | static int ovl_casefold(struct ovl_readdir_data *rdd, const char *str, int len,
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| 74 | char **dst)
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| 75 | {
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| 76 | const struct qstr qstr = { .name = str, .len = len };
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| 77 | char *cf_name;
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| 78 | int cf_len;
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| 79 |
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| 80 | if (!IS_ENABLED(CONFIG_UNICODE) || !rdd->map ||
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| 81 | name_is_dot_dotdot(str, len))
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| 82 | return 0;
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| 83 |
|
| 84 | cf_name = kmalloc(NAME_MAX, GFP_KERNEL);
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| 85 | if (!cf_name) {
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| 86 | rdd->err = -ENOMEM;
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| 87 | return -ENOMEM;
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| 88 | }
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| 89 |
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| 90 | cf_len = utf8_casefold(rdd->map, &qstr, cf_name, NAME_MAX);
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| 91 | if (cf_len > 0)
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| 92 | *dst = cf_name;
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| 93 | else
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| 94 | kfree(cf_name);
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| 95 |
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| 96 | return cf_len;
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| 97 | }
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| 98 |
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| 99 | static bool ovl_cache_entry_find_link(const char *name, int len,
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| 100 | struct rb_node ***link,
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| 101 | struct rb_node **parent)
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| 102 | {
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| 103 | bool found = false;
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| 104 | struct rb_node **newp = *link;
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| 105 |
|
| 106 | while (!found && *newp) {
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| 107 | int cmp;
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| 108 | struct ovl_cache_entry *tmp;
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| 109 |
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| 110 | *parent = *newp;
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| 111 | tmp = ovl_cache_entry_from_node(*newp);
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| 112 | cmp = strncmp(name, tmp->c_name, len);
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| 113 | if (cmp > 0)
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| 114 | newp = &tmp->node.rb_right;
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| 115 | else if (cmp < 0 || len < tmp->c_len)
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| 116 | newp = &tmp->node.rb_left;
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| 117 | else
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| 118 | found = true;
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| 119 | }
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| 120 | *link = newp;
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| 121 |
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| 122 | return found;
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| 123 | }
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| 124 |
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| 125 | static struct ovl_cache_entry *ovl_cache_entry_find(struct rb_root *root,
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| 126 | const char *name, int len)
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| 127 | {
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| 128 | struct rb_node *node = root->rb_node;
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| 129 | int cmp;
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| 130 |
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| 131 | while (node) {
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| 132 | struct ovl_cache_entry *p = ovl_cache_entry_from_node(node);
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| 133 |
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| 134 | cmp = strncmp(name, p->c_name, len);
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| 135 | if (cmp > 0)
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| 136 | node = p->node.rb_right;
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| 137 | else if (cmp < 0 || len < p->c_len)
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| 138 | node = p->node.rb_left;
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| 139 | else
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| 140 | return p;
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| 141 | }
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| 142 |
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| 143 | return NULL;
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| 144 | }
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| 145 |
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| 146 | static bool ovl_calc_d_ino(struct ovl_readdir_data *rdd,
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| 147 | struct ovl_cache_entry *p)
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| 148 | {
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| 149 |
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| 150 | if (!rdd->dentry)
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| 151 | return false;
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| 152 |
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| 153 |
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| 154 | if (ovl_xino_bits(OVL_FS(rdd->dentry->d_sb)))
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| 155 | return true;
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| 156 |
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| 157 |
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| 158 | if (name_is_dotdot(p->name, p->len))
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| 159 | return true;
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| 160 |
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| 161 |
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| 162 | if (!rdd->is_upper)
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| 163 | return false;
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| 164 |
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| 165 | |
| 166 | * Recalc d_ino for '.' and for all entries if dir is impure (contains
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| 167 | * copied up entries)
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| 168 |
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| 169 | if (name_is_dot(p->name, p->len) ||
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| 170 | ovl_test_flag(OVL_IMPURE, d_inode(rdd->dentry)))
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| 171 | return true;
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| 172 |
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| 173 | return false;
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| 174 | }
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| 175 |
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| 176 | static struct ovl_cache_entry *ovl_cache_entry_new(struct ovl_readdir_data *rdd,
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| 177 | const char *name, int len,
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| 178 | const char *c_name, int c_len,
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| 179 | u64 ino, unsigned int d_type)
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| 180 | {
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| 181 | struct ovl_cache_entry *p;
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| 182 |
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| 183 | p = kmalloc_flex(*p, name, len + 1);
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| 184 | if (!p)
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| 185 | return NULL;
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| 186 |
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| 187 | memcpy(p->name, name, len);
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| 188 | p->name[len] = '\0';
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| 189 | p->len = len;
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| 190 | p->type = d_type;
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| 191 | p->real_ino = ino;
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| 192 | p->ino = ino;
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| 193 |
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| 194 | if (ovl_calc_d_ino(rdd, p))
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| 195 | p->ino = 0;
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| 196 | p->is_upper = rdd->is_upper;
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| 197 | p->is_whiteout = false;
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| 198 |
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| 199 | p->check_xwhiteout = rdd->in_xwhiteouts_dir && d_type == DT_REG;
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| 200 |
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| 201 | if (c_name && c_name != name) {
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| 202 | p->c_name = c_name;
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| 203 | p->c_len = c_len;
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| 204 | } else {
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| 205 | p->c_name = p->name;
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| 206 | p->c_len = len;
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| 207 | }
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| 208 |
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| 209 | if (d_type == DT_CHR) {
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| 210 | p->next_maybe_whiteout = rdd->first_maybe_whiteout;
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| 211 | rdd->first_maybe_whiteout = p;
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| 212 | }
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| 213 | return p;
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| 214 | }
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| 215 |
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| 216 |
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| 217 | static int ovl_cache_entry_add_rb(struct ovl_readdir_data *rdd,
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| 218 | const char *name, int len,
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| 219 | const char *c_name, int c_len,
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| 220 | u64 ino,
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| 221 | unsigned int d_type)
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| 222 | {
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| 223 | struct rb_node **newp = &rdd->root->rb_node;
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| 224 | struct rb_node *parent = NULL;
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| 225 | struct ovl_cache_entry *p;
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| 226 |
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| 227 | if (ovl_cache_entry_find_link(c_name, c_len, &newp, &parent))
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| 228 | return 0;
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| 229 |
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| 230 | p = ovl_cache_entry_new(rdd, name, len, c_name, c_len, ino, d_type);
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| 231 | if (p == NULL) {
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| 232 | rdd->err = -ENOMEM;
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| 233 | return -ENOMEM;
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| 234 | }
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| 235 |
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| 236 | list_add_tail(&p->l_node, rdd->list);
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| 237 | rb_link_node(&p->node, parent, newp);
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| 238 | rb_insert_color(&p->node, rdd->root);
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| 239 |
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| 240 | return 1;
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| 241 | }
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| 242 |
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| 243 |
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| 244 | static int ovl_fill_lowest(struct ovl_readdir_data *rdd,
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| 245 | const char *name, int namelen,
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| 246 | const char *c_name, int c_len,
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| 247 | loff_t offset, u64 ino, unsigned int d_type)
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| 248 | {
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| 249 | struct ovl_cache_entry *p;
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| 250 |
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| 251 | p = ovl_cache_entry_find(rdd->root, c_name, c_len);
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| 252 | if (p) {
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| 253 | list_move_tail(&p->l_node, &rdd->middle);
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| 254 | return 0;
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| 255 | } else {
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| 256 | p = ovl_cache_entry_new(rdd, name, namelen, c_name, c_len,
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| 257 | ino, d_type);
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| 258 | if (p == NULL)
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| 259 | rdd->err = -ENOMEM;
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| 260 | else
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| 261 | list_add_tail(&p->l_node, &rdd->middle);
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| 262 | }
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| 263 |
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| 264 | return rdd->err ?: 1;
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| 265 | }
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| 266 |
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| 267 | static void ovl_cache_entry_free(struct ovl_cache_entry *p)
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| 268 | {
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| 269 | if (p->c_name != p->name)
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| 270 | kfree(p->c_name);
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| 271 | kfree(p);
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| 272 | }
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| 273 |
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| 274 | void ovl_cache_free(struct list_head *list)
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| 275 | {
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| 276 | struct ovl_cache_entry *p;
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| 277 | struct ovl_cache_entry *n;
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| 278 |
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| 279 | list_for_each_entry_safe(p, n, list, l_node)
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| 280 | ovl_cache_entry_free(p);
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| 281 |
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| 282 | INIT_LIST_HEAD(list);
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| 283 | }
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| 284 |
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| 285 | void ovl_dir_cache_free(struct inode *inode)
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| 286 | {
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| 287 | struct ovl_dir_cache *cache = ovl_dir_cache(inode);
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| 288 |
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| 289 | if (cache) {
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| 290 | ovl_cache_free(&cache->entries);
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| 291 | kfree(cache);
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| 292 | }
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| 293 | }
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| 294 |
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| 295 | static void ovl_cache_put(struct ovl_dir_file *od, struct inode *inode)
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| 296 | {
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| 297 | struct ovl_dir_cache *cache = od->cache;
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| 298 |
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| 299 | WARN_ON(cache->refcount <= 0);
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| 300 | cache->refcount--;
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| 301 | if (!cache->refcount) {
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| 302 | if (ovl_dir_cache(inode) == cache)
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| 303 | ovl_set_dir_cache(inode, NULL);
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| 304 |
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| 305 | ovl_cache_free(&cache->entries);
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| 306 | kfree(cache);
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| 307 | }
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| 308 | }
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| 309 |
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| 310 | static bool ovl_fill_merge(struct dir_context *ctx, const char *name,
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| 311 | int namelen, loff_t offset, u64 ino,
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| 312 | unsigned int d_type)
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| 313 | {
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| 314 | struct ovl_readdir_data *rdd =
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| 315 | container_of(ctx, struct ovl_readdir_data, ctx);
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| 316 | struct ovl_fs *ofs = OVL_FS(rdd->dentry->d_sb);
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| 317 | const char *c_name = NULL;
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| 318 | char *cf_name = NULL;
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| 319 | int c_len = 0, ret;
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| 320 |
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| 321 | if (ofs->casefold)
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| 322 | c_len = ovl_casefold(rdd, name, namelen, &cf_name);
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| 323 |
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| 324 | if (rdd->err)
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| 325 | return false;
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| 326 |
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| 327 | if (c_len <= 0) {
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| 328 | c_name = name;
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| 329 | c_len = namelen;
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| 330 | } else {
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| 331 | c_name = cf_name;
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| 332 | }
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| 333 |
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| 334 | rdd->count++;
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| 335 | if (!rdd->is_lowest)
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| 336 | ret = ovl_cache_entry_add_rb(rdd, name, namelen, c_name, c_len, ino, d_type);
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| 337 | else
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| 338 | ret = ovl_fill_lowest(rdd, name, namelen, c_name, c_len, offset, ino, d_type);
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| 339 |
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| 340 | |
| 341 | * If ret == 1, that means that c_name is being used as part of struct
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| 342 | * ovl_cache_entry and will be freed at ovl_cache_free(). Otherwise,
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| 343 | * c_name was found in the rb-tree so we can free it here.
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| 344 |
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| 345 | if (ret != 1 && c_name != name)
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| 346 | kfree(c_name);
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| 347 |
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| 348 | return ret >= 0;
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| 349 | }
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| 350 |
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| 351 | static int ovl_check_whiteouts(const struct path *path, struct ovl_readdir_data *rdd)
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| 352 | {
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| 353 | struct dentry *dentry, *dir = path->dentry;
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| 354 |
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| 355 | while (rdd->first_maybe_whiteout) {
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| 356 | struct ovl_cache_entry *p =
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| 357 | rdd->first_maybe_whiteout;
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| 358 | rdd->first_maybe_whiteout = p->next_maybe_whiteout;
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| 359 | dentry = lookup_one_positive_killable(mnt_idmap(path->mnt),
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| 360 | &QSTR_LEN(p->name, p->len),
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| 361 | dir);
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| 362 | if (!IS_ERR(dentry)) {
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| 363 | p->is_whiteout = ovl_is_whiteout(dentry);
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| 364 | dput(dentry);
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| 365 | } else if (PTR_ERR(dentry) == -EINTR) {
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| 366 | return -EINTR;
|
| 367 | }
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| 368 | }
|
| 369 |
|
| 370 | return 0;
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| 371 | }
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| 372 |
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| 373 | static inline int ovl_dir_read(const struct path *realpath,
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| 374 | struct ovl_readdir_data *rdd)
|
| 375 | {
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| 376 | struct file *realfile;
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| 377 | int err;
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| 378 |
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| 379 | realfile = ovl_path_open(realpath, O_RDONLY | O_LARGEFILE);
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| 380 | if (IS_ERR(realfile))
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| 381 | return PTR_ERR(realfile);
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| 382 |
|
| 383 | rdd->first_maybe_whiteout = NULL;
|
| 384 | rdd->ctx.pos = 0;
|
| 385 | do {
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| 386 | rdd->count = 0;
|
| 387 | rdd->err = 0;
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| 388 | err = iterate_dir(realfile, &rdd->ctx);
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| 389 | if (err >= 0)
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| 390 | err = rdd->err;
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| 391 | } while (!err && rdd->count);
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| 392 |
|
| 393 | if (!err && rdd->first_maybe_whiteout && rdd->dentry)
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| 394 | err = ovl_check_whiteouts(realpath, rdd);
|
| 395 |
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| 396 | fput(realfile);
|
| 397 |
|
| 398 | return err;
|
| 399 | }
|
| 400 |
|
| 401 | static void ovl_dir_reset(struct file *file)
|
| 402 | {
|
| 403 | struct ovl_dir_file *od = file->private_data;
|
| 404 | struct ovl_dir_cache *cache = od->cache;
|
| 405 | struct inode *inode = file_inode(file);
|
| 406 | bool is_real;
|
| 407 |
|
| 408 | if (cache && ovl_inode_version_get(inode) != cache->version) {
|
| 409 | ovl_cache_put(od, inode);
|
| 410 | od->cache = NULL;
|
| 411 | od->cursor = NULL;
|
| 412 | }
|
| 413 | is_real = ovl_dir_is_real(inode);
|
| 414 | if (od->is_real != is_real) {
|
| 415 |
|
| 416 | if (WARN_ON(is_real))
|
| 417 | return;
|
| 418 | od->is_real = false;
|
| 419 | }
|
| 420 | }
|
| 421 |
|
| 422 | static int ovl_dir_read_merged(struct dentry *dentry, struct list_head *list,
|
| 423 | struct rb_root *root)
|
| 424 | {
|
| 425 | int err;
|
| 426 | struct path realpath;
|
| 427 | struct ovl_readdir_data rdd = {
|
| 428 | .ctx.actor = ovl_fill_merge,
|
| 429 | .ctx.count = INT_MAX,
|
| 430 | .dentry = dentry,
|
| 431 | .list = list,
|
| 432 | .root = root,
|
| 433 | .is_lowest = false,
|
| 434 | .map = NULL,
|
| 435 | };
|
| 436 | int idx, next;
|
| 437 | const struct ovl_layer *layer;
|
| 438 | struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
|
| 439 |
|
| 440 | for (idx = 0; idx != -1; idx = next) {
|
| 441 | next = ovl_path_next(idx, dentry, &realpath, &layer);
|
| 442 |
|
| 443 | if (ofs->casefold)
|
| 444 | rdd.map = sb_encoding(realpath.dentry->d_sb);
|
| 445 |
|
| 446 | rdd.is_upper = ovl_dentry_upper(dentry) == realpath.dentry;
|
| 447 | rdd.in_xwhiteouts_dir = layer->has_xwhiteouts &&
|
| 448 | ovl_dentry_has_xwhiteouts(dentry);
|
| 449 |
|
| 450 | if (next != -1) {
|
| 451 | err = ovl_dir_read(&realpath, &rdd);
|
| 452 | if (err)
|
| 453 | break;
|
| 454 | } else {
|
| 455 | |
| 456 | * Insert lowest layer entries before upper ones, this
|
| 457 | * allows offsets to be reasonably constant
|
| 458 |
|
| 459 | list_add(&rdd.middle, rdd.list);
|
| 460 | rdd.is_lowest = true;
|
| 461 | err = ovl_dir_read(&realpath, &rdd);
|
| 462 | list_del(&rdd.middle);
|
| 463 | }
|
| 464 | }
|
| 465 | return err;
|
| 466 | }
|
| 467 |
|
| 468 | static void ovl_seek_cursor(struct ovl_dir_file *od, loff_t pos)
|
| 469 | {
|
| 470 | struct list_head *p;
|
| 471 | loff_t off = 0;
|
| 472 |
|
| 473 | list_for_each(p, &od->cache->entries) {
|
| 474 | if (off >= pos)
|
| 475 | break;
|
| 476 | off++;
|
| 477 | }
|
| 478 |
|
| 479 | od->cursor = p;
|
| 480 | }
|
| 481 |
|
| 482 | static struct ovl_dir_cache *ovl_cache_get(struct dentry *dentry)
|
| 483 | {
|
| 484 | int res;
|
| 485 | struct ovl_dir_cache *cache;
|
| 486 | struct inode *inode = d_inode(dentry);
|
| 487 |
|
| 488 | cache = ovl_dir_cache(inode);
|
| 489 | if (cache && ovl_inode_version_get(inode) == cache->version) {
|
| 490 | WARN_ON(!cache->refcount);
|
| 491 | cache->refcount++;
|
| 492 | return cache;
|
| 493 | }
|
| 494 | ovl_set_dir_cache(d_inode(dentry), NULL);
|
| 495 |
|
| 496 | cache = kzalloc_obj(struct ovl_dir_cache);
|
| 497 | if (!cache)
|
| 498 | return ERR_PTR(-ENOMEM);
|
| 499 |
|
| 500 | cache->refcount = 1;
|
| 501 | INIT_LIST_HEAD(&cache->entries);
|
| 502 | cache->root = RB_ROOT;
|
| 503 |
|
| 504 | res = ovl_dir_read_merged(dentry, &cache->entries, &cache->root);
|
| 505 | if (res) {
|
| 506 | ovl_cache_free(&cache->entries);
|
| 507 | kfree(cache);
|
| 508 | return ERR_PTR(res);
|
| 509 | }
|
| 510 |
|
| 511 | cache->version = ovl_inode_version_get(inode);
|
| 512 | ovl_set_dir_cache(inode, cache);
|
| 513 |
|
| 514 | return cache;
|
| 515 | }
|
| 516 |
|
| 517 |
|
| 518 | static u64 ovl_remap_lower_ino(u64 ino, int xinobits, int fsid,
|
| 519 | const char *name, int namelen, bool warn)
|
| 520 | {
|
| 521 | unsigned int xinoshift = 64 - xinobits;
|
| 522 |
|
| 523 | if (unlikely(ino >> xinoshift)) {
|
| 524 | if (warn) {
|
| 525 | pr_warn_ratelimited("d_ino too big (%.*s, ino=%llu, xinobits=%d)\n",
|
| 526 | namelen, name, ino, xinobits);
|
| 527 | }
|
| 528 | return ino;
|
| 529 | }
|
| 530 |
|
| 531 | |
| 532 | * The lowest xinobit is reserved for mapping the non-peresistent inode
|
| 533 | * numbers range, but this range is only exposed via st_ino, not here.
|
| 534 |
|
| 535 | return ino | ((u64)fsid) << (xinoshift + 1);
|
| 536 | }
|
| 537 |
|
| 538 | |
| 539 | * Set d_ino for upper entries if needed. Non-upper entries should always report
|
| 540 | * the uppermost real inode ino and should not call this function.
|
| 541 | *
|
| 542 | * When not all layer are on same fs, report real ino also for upper.
|
| 543 | *
|
| 544 | * When all layers are on the same fs, and upper has a reference to
|
| 545 | * copy up origin, call vfs_getattr() on the overlay entry to make
|
| 546 | * sure that d_ino will be consistent with st_ino from stat(2).
|
| 547 | *
|
| 548 | * Also checks the overlay.whiteout xattr by doing a full lookup which will return
|
| 549 | * negative in this case.
|
| 550 |
|
| 551 | static int ovl_cache_update(const struct path *path, struct ovl_cache_entry *p, bool update_ino)
|
| 552 |
|
| 553 | {
|
| 554 | struct dentry *dir = path->dentry;
|
| 555 | struct ovl_fs *ofs = OVL_FS(dir->d_sb);
|
| 556 | struct dentry *this = NULL;
|
| 557 | enum ovl_path_type type;
|
| 558 | u64 ino = p->real_ino;
|
| 559 | int xinobits = ovl_xino_bits(ofs);
|
| 560 | int err = 0;
|
| 561 |
|
| 562 | if (!ovl_same_dev(ofs) && !p->check_xwhiteout)
|
| 563 | goto out;
|
| 564 |
|
| 565 | if (name_is_dot_dotdot(p->name, p->len)) {
|
| 566 | if (p->len == 1) {
|
| 567 | this = dget(dir);
|
| 568 | goto get;
|
| 569 | }
|
| 570 | if (p->len == 2) {
|
| 571 |
|
| 572 | this = dget(dir->d_parent);
|
| 573 | goto get;
|
| 574 | }
|
| 575 | }
|
| 576 |
|
| 577 | this = lookup_one(mnt_idmap(path->mnt), &QSTR_LEN(p->name, p->len), dir);
|
| 578 | if (IS_ERR_OR_NULL(this) || !this->d_inode) {
|
| 579 |
|
| 580 | p->is_whiteout = true;
|
| 581 | if (IS_ERR(this)) {
|
| 582 | err = PTR_ERR(this);
|
| 583 | this = NULL;
|
| 584 | goto fail;
|
| 585 | }
|
| 586 | goto out;
|
| 587 | }
|
| 588 |
|
| 589 | get:
|
| 590 | if (!ovl_same_dev(ofs) || !update_ino)
|
| 591 | goto out;
|
| 592 |
|
| 593 | type = ovl_path_type(this);
|
| 594 | if (OVL_TYPE_ORIGIN(type)) {
|
| 595 | struct kstat stat;
|
| 596 | struct path statpath = *path;
|
| 597 |
|
| 598 | statpath.dentry = this;
|
| 599 | err = vfs_getattr(&statpath, &stat, STATX_INO, 0);
|
| 600 | if (err)
|
| 601 | goto fail;
|
| 602 |
|
| 603 | |
| 604 | * Directory inode is always on overlay st_dev.
|
| 605 | * Non-dir with ovl_same_dev() could be on pseudo st_dev in case
|
| 606 | * of xino bits overflow.
|
| 607 |
|
| 608 | WARN_ON_ONCE(S_ISDIR(stat.mode) &&
|
| 609 | dir->d_sb->s_dev != stat.dev);
|
| 610 | ino = stat.ino;
|
| 611 | } else if (xinobits && !OVL_TYPE_UPPER(type)) {
|
| 612 | ino = ovl_remap_lower_ino(ino, xinobits,
|
| 613 | ovl_layer_lower(this)->fsid,
|
| 614 | p->name, p->len,
|
| 615 | ovl_xino_warn(ofs));
|
| 616 | }
|
| 617 |
|
| 618 | out:
|
| 619 | p->ino = ino;
|
| 620 | dput(this);
|
| 621 | return err;
|
| 622 |
|
| 623 | fail:
|
| 624 | pr_warn_ratelimited("failed to look up (%s) for ino (%i)\n",
|
| 625 | p->name, err);
|
| 626 | goto out;
|
| 627 | }
|
| 628 |
|
| 629 | static bool ovl_fill_plain(struct dir_context *ctx, const char *name,
|
| 630 | int namelen, loff_t offset, u64 ino,
|
| 631 | unsigned int d_type)
|
| 632 | {
|
| 633 | struct ovl_cache_entry *p;
|
| 634 | struct ovl_readdir_data *rdd =
|
| 635 | container_of(ctx, struct ovl_readdir_data, ctx);
|
| 636 |
|
| 637 | rdd->count++;
|
| 638 | p = ovl_cache_entry_new(rdd, name, namelen, NULL, 0, ino, d_type);
|
| 639 | if (p == NULL) {
|
| 640 | rdd->err = -ENOMEM;
|
| 641 | return false;
|
| 642 | }
|
| 643 | list_add_tail(&p->l_node, rdd->list);
|
| 644 |
|
| 645 | return true;
|
| 646 | }
|
| 647 |
|
| 648 | static int ovl_dir_read_impure(const struct path *path, struct list_head *list,
|
| 649 | struct rb_root *root)
|
| 650 | {
|
| 651 | int err;
|
| 652 | struct path realpath;
|
| 653 | struct ovl_cache_entry *p, *n;
|
| 654 | struct ovl_readdir_data rdd = {
|
| 655 | .ctx.actor = ovl_fill_plain,
|
| 656 | .ctx.count = INT_MAX,
|
| 657 | .list = list,
|
| 658 | .root = root,
|
| 659 | };
|
| 660 |
|
| 661 | INIT_LIST_HEAD(list);
|
| 662 | *root = RB_ROOT;
|
| 663 | ovl_path_upper(path->dentry, &realpath);
|
| 664 |
|
| 665 | err = ovl_dir_read(&realpath, &rdd);
|
| 666 | if (err)
|
| 667 | return err;
|
| 668 |
|
| 669 | list_for_each_entry_safe(p, n, list, l_node) {
|
| 670 | if (!name_is_dot_dotdot(p->name, p->len)) {
|
| 671 | err = ovl_cache_update(path, p, true);
|
| 672 | if (err)
|
| 673 | return err;
|
| 674 | }
|
| 675 | if (p->ino == p->real_ino) {
|
| 676 | list_del(&p->l_node);
|
| 677 | ovl_cache_entry_free(p);
|
| 678 | } else {
|
| 679 | struct rb_node **newp = &root->rb_node;
|
| 680 | struct rb_node *parent = NULL;
|
| 681 |
|
| 682 | if (WARN_ON(ovl_cache_entry_find_link(p->name, p->len,
|
| 683 | &newp, &parent)))
|
| 684 | return -EIO;
|
| 685 |
|
| 686 | rb_link_node(&p->node, parent, newp);
|
| 687 | rb_insert_color(&p->node, root);
|
| 688 | }
|
| 689 | }
|
| 690 | return 0;
|
| 691 | }
|
| 692 |
|
| 693 | static struct ovl_dir_cache *ovl_cache_get_impure(const struct path *path)
|
| 694 | {
|
| 695 | int res;
|
| 696 | struct dentry *dentry = path->dentry;
|
| 697 | struct inode *inode = d_inode(dentry);
|
| 698 | struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
|
| 699 | struct ovl_dir_cache *cache;
|
| 700 |
|
| 701 | cache = ovl_dir_cache(inode);
|
| 702 | if (cache && ovl_inode_version_get(inode) == cache->version)
|
| 703 | return cache;
|
| 704 |
|
| 705 |
|
| 706 | ovl_dir_cache_free(inode);
|
| 707 | ovl_set_dir_cache(inode, NULL);
|
| 708 |
|
| 709 | cache = kzalloc_obj(struct ovl_dir_cache);
|
| 710 | if (!cache)
|
| 711 | return ERR_PTR(-ENOMEM);
|
| 712 |
|
| 713 | res = ovl_dir_read_impure(path, &cache->entries, &cache->root);
|
| 714 | if (res) {
|
| 715 | ovl_cache_free(&cache->entries);
|
| 716 | kfree(cache);
|
| 717 | return ERR_PTR(res);
|
| 718 | }
|
| 719 | if (list_empty(&cache->entries)) {
|
| 720 | |
| 721 | * A good opportunity to get rid of an unneeded "impure" flag.
|
| 722 | * Removing the "impure" xattr is best effort.
|
| 723 |
|
| 724 | if (!ovl_want_write(dentry)) {
|
| 725 | ovl_removexattr(ofs, ovl_dentry_upper(dentry),
|
| 726 | OVL_XATTR_IMPURE);
|
| 727 | ovl_drop_write(dentry);
|
| 728 | }
|
| 729 | ovl_clear_flag(OVL_IMPURE, inode);
|
| 730 | kfree(cache);
|
| 731 | return NULL;
|
| 732 | }
|
| 733 |
|
| 734 | cache->version = ovl_inode_version_get(inode);
|
| 735 | ovl_set_dir_cache(inode, cache);
|
| 736 |
|
| 737 | return cache;
|
| 738 | }
|
| 739 |
|
| 740 | struct ovl_readdir_translate {
|
| 741 | struct dir_context *orig_ctx;
|
| 742 | struct ovl_dir_cache *cache;
|
| 743 | struct dir_context ctx;
|
| 744 | u64 parent_ino;
|
| 745 | int fsid;
|
| 746 | int xinobits;
|
| 747 | bool xinowarn;
|
| 748 | };
|
| 749 |
|
| 750 | static bool ovl_fill_real(struct dir_context *ctx, const char *name,
|
| 751 | int namelen, loff_t offset, u64 ino,
|
| 752 | unsigned int d_type)
|
| 753 | {
|
| 754 | struct ovl_readdir_translate *rdt =
|
| 755 | container_of(ctx, struct ovl_readdir_translate, ctx);
|
| 756 | struct dir_context *orig_ctx = rdt->orig_ctx;
|
| 757 | bool res;
|
| 758 |
|
| 759 | if (rdt->parent_ino && name_is_dotdot(name, namelen)) {
|
| 760 | ino = rdt->parent_ino;
|
| 761 | } else if (rdt->cache) {
|
| 762 | struct ovl_cache_entry *p;
|
| 763 |
|
| 764 | p = ovl_cache_entry_find(&rdt->cache->root, name, namelen);
|
| 765 | if (p)
|
| 766 | ino = p->ino;
|
| 767 | } else if (rdt->xinobits) {
|
| 768 | ino = ovl_remap_lower_ino(ino, rdt->xinobits, rdt->fsid,
|
| 769 | name, namelen, rdt->xinowarn);
|
| 770 | }
|
| 771 |
|
| 772 | res = orig_ctx->actor(orig_ctx, name, namelen, offset, ino, d_type);
|
| 773 | ctx->count = orig_ctx->count;
|
| 774 |
|
| 775 | return res;
|
| 776 | }
|
| 777 |
|
| 778 | static bool ovl_is_impure_dir(struct file *file)
|
| 779 | {
|
| 780 | struct ovl_dir_file *od = file->private_data;
|
| 781 | struct inode *dir = file_inode(file);
|
| 782 |
|
| 783 | |
| 784 | * Only upper dir can be impure, but if we are in the middle of
|
| 785 | * iterating a lower real dir, dir could be copied up and marked
|
| 786 | * impure. We only want the impure cache if we started iterating
|
| 787 | * a real upper dir to begin with.
|
| 788 |
|
| 789 | return od->is_upper && ovl_test_flag(OVL_IMPURE, dir);
|
| 790 |
|
| 791 | }
|
| 792 |
|
| 793 | static int ovl_iterate_real(struct file *file, struct dir_context *ctx)
|
| 794 | {
|
| 795 | int err;
|
| 796 | struct ovl_dir_file *od = file->private_data;
|
| 797 | struct dentry *dir = file->f_path.dentry;
|
| 798 | struct ovl_fs *ofs = OVL_FS(dir->d_sb);
|
| 799 | const struct ovl_layer *lower_layer = ovl_layer_lower(dir);
|
| 800 | struct ovl_readdir_translate rdt = {
|
| 801 | .ctx.actor = ovl_fill_real,
|
| 802 | .ctx.count = ctx->count,
|
| 803 | .orig_ctx = ctx,
|
| 804 | .xinobits = ovl_xino_bits(ofs),
|
| 805 | .xinowarn = ovl_xino_warn(ofs),
|
| 806 | };
|
| 807 |
|
| 808 | if (rdt.xinobits && lower_layer)
|
| 809 | rdt.fsid = lower_layer->fsid;
|
| 810 |
|
| 811 | if (OVL_TYPE_MERGE(ovl_path_type(dir->d_parent))) {
|
| 812 | struct kstat stat;
|
| 813 | struct path statpath = file->f_path;
|
| 814 |
|
| 815 | statpath.dentry = dir->d_parent;
|
| 816 | err = vfs_getattr(&statpath, &stat, STATX_INO, 0);
|
| 817 | if (err)
|
| 818 | return err;
|
| 819 |
|
| 820 | WARN_ON_ONCE(dir->d_sb->s_dev != stat.dev);
|
| 821 | rdt.parent_ino = stat.ino;
|
| 822 | }
|
| 823 |
|
| 824 | if (ovl_is_impure_dir(file)) {
|
| 825 | rdt.cache = ovl_cache_get_impure(&file->f_path);
|
| 826 | if (IS_ERR(rdt.cache))
|
| 827 | return PTR_ERR(rdt.cache);
|
| 828 | }
|
| 829 |
|
| 830 | err = iterate_dir(od->realfile, &rdt.ctx);
|
| 831 | ctx->pos = rdt.ctx.pos;
|
| 832 |
|
| 833 | return err;
|
| 834 | }
|
| 835 |
|
| 836 | static int ovl_iterate_merged(struct file *file, struct dir_context *ctx)
|
| 837 | {
|
| 838 | struct ovl_dir_file *od = file->private_data;
|
| 839 | struct dentry *dentry = file->f_path.dentry;
|
| 840 | struct ovl_cache_entry *p;
|
| 841 | int err;
|
| 842 |
|
| 843 | if (!od->cache) {
|
| 844 | struct ovl_dir_cache *cache;
|
| 845 |
|
| 846 | cache = ovl_cache_get(dentry);
|
| 847 | if (IS_ERR(cache))
|
| 848 | return PTR_ERR(cache);
|
| 849 |
|
| 850 | od->cache = cache;
|
| 851 | ovl_seek_cursor(od, ctx->pos);
|
| 852 | }
|
| 853 |
|
| 854 | while (od->cursor != &od->cache->entries) {
|
| 855 | p = list_entry(od->cursor, struct ovl_cache_entry, l_node);
|
| 856 | if (!p->is_whiteout) {
|
| 857 | if (!p->ino || p->check_xwhiteout) {
|
| 858 | err = ovl_cache_update(&file->f_path, p, !p->ino);
|
| 859 | if (err)
|
| 860 | return err;
|
| 861 | }
|
| 862 | }
|
| 863 |
|
| 864 | if (!p->is_whiteout) {
|
| 865 | if (!dir_emit(ctx, p->name, p->len, p->ino, p->type))
|
| 866 | break;
|
| 867 | }
|
| 868 | od->cursor = p->l_node.next;
|
| 869 | ctx->pos++;
|
| 870 | }
|
| 871 | return 0;
|
| 872 | }
|
| 873 |
|
| 874 | static bool ovl_need_adjust_d_ino(struct file *file)
|
| 875 | {
|
| 876 | struct dentry *dentry = file->f_path.dentry;
|
| 877 | struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
|
| 878 |
|
| 879 |
|
| 880 | if (ovl_xino_bits(ofs))
|
| 881 | return true;
|
| 882 |
|
| 883 |
|
| 884 | if (!ovl_same_fs(ofs))
|
| 885 | return false;
|
| 886 |
|
| 887 |
|
| 888 | if (ovl_is_impure_dir(file) ||
|
| 889 | OVL_TYPE_MERGE(ovl_path_type(dentry->d_parent)))
|
| 890 | return true;
|
| 891 |
|
| 892 |
|
| 893 | return false;
|
| 894 | }
|
| 895 |
|
| 896 |
|
| 897 | static int ovl_iterate(struct file *file, struct dir_context *ctx)
|
| 898 | {
|
| 899 | struct ovl_dir_file *od = file->private_data;
|
| 900 |
|
| 901 | if (!ctx->pos)
|
| 902 | ovl_dir_reset(file);
|
| 903 |
|
| 904 | with_ovl_creds(file_dentry(file)->d_sb) {
|
| 905 | if (!od->is_real)
|
| 906 | return ovl_iterate_merged(file, ctx);
|
| 907 |
|
| 908 | if (ovl_need_adjust_d_ino(file))
|
| 909 | return ovl_iterate_real(file, ctx);
|
| 910 |
|
| 911 | return iterate_dir(od->realfile, ctx);
|
| 912 | }
|
| 913 | }
|
| 914 |
|
| 915 | static loff_t ovl_dir_llseek(struct file *file, loff_t offset, int origin)
|
| 916 | {
|
| 917 | loff_t res;
|
| 918 | struct ovl_dir_file *od = file->private_data;
|
| 919 |
|
| 920 | inode_lock(file_inode(file));
|
| 921 | if (!file->f_pos)
|
| 922 | ovl_dir_reset(file);
|
| 923 |
|
| 924 | if (od->is_real) {
|
| 925 | res = vfs_llseek(od->realfile, offset, origin);
|
| 926 | file->f_pos = od->realfile->f_pos;
|
| 927 | } else {
|
| 928 | res = -EINVAL;
|
| 929 |
|
| 930 | switch (origin) {
|
| 931 | case SEEK_CUR:
|
| 932 | offset += file->f_pos;
|
| 933 | break;
|
| 934 | case SEEK_SET:
|
| 935 | break;
|
| 936 | default:
|
| 937 | goto out_unlock;
|
| 938 | }
|
| 939 | if (offset < 0)
|
| 940 | goto out_unlock;
|
| 941 |
|
| 942 | if (offset != file->f_pos) {
|
| 943 | file->f_pos = offset;
|
| 944 | if (od->cache)
|
| 945 | ovl_seek_cursor(od, offset);
|
| 946 | }
|
| 947 | res = offset;
|
| 948 | }
|
| 949 | out_unlock:
|
| 950 | inode_unlock(file_inode(file));
|
| 951 |
|
| 952 | return res;
|
| 953 | }
|
| 954 |
|
| 955 | static struct file *ovl_dir_open_realfile(const struct file *file,
|
| 956 | const struct path *realpath)
|
| 957 | {
|
| 958 | with_ovl_creds(file_inode(file)->i_sb)
|
| 959 | return ovl_path_open(realpath, O_RDONLY | (file->f_flags & O_LARGEFILE));
|
| 960 | }
|
| 961 |
|
| 962 | |
| 963 | * Like ovl_real_fdget(), returns upperfile if dir was copied up since open.
|
| 964 | * Unlike ovl_real_fdget(), this caches upperfile in file->private_data.
|
| 965 | *
|
| 966 | * TODO: use same abstract type for file->private_data of dir and file so
|
| 967 | * upperfile could also be cached for files as well.
|
| 968 |
|
| 969 | struct file *ovl_dir_real_file(const struct file *file, bool want_upper)
|
| 970 | {
|
| 971 |
|
| 972 | struct ovl_dir_file *od = file->private_data;
|
| 973 | struct dentry *dentry = file->f_path.dentry;
|
| 974 | struct file *old, *realfile = od->realfile;
|
| 975 |
|
| 976 | if (!OVL_TYPE_UPPER(ovl_path_type(dentry)))
|
| 977 | return want_upper ? NULL : realfile;
|
| 978 |
|
| 979 | |
| 980 | * Need to check if we started out being a lower dir, but got copied up
|
| 981 |
|
| 982 | if (!od->is_upper) {
|
| 983 | realfile = READ_ONCE(od->upperfile);
|
| 984 | if (!realfile) {
|
| 985 | struct path upperpath;
|
| 986 |
|
| 987 | ovl_path_upper(dentry, &upperpath);
|
| 988 | realfile = ovl_dir_open_realfile(file, &upperpath);
|
| 989 | if (IS_ERR(realfile))
|
| 990 | return realfile;
|
| 991 |
|
| 992 | old = cmpxchg_release(&od->upperfile, NULL, realfile);
|
| 993 | if (old) {
|
| 994 | fput(realfile);
|
| 995 | realfile = old;
|
| 996 | }
|
| 997 | }
|
| 998 | }
|
| 999 |
|
| 1000 | return realfile;
|
| 1001 | }
|
| 1002 |
|
| 1003 | static int ovl_dir_fsync(struct file *file, loff_t start, loff_t end,
|
| 1004 | int datasync)
|
| 1005 | {
|
| 1006 | struct file *realfile;
|
| 1007 | int err;
|
| 1008 |
|
| 1009 | err = ovl_sync_status(OVL_FS(file_inode(file)->i_sb));
|
| 1010 | if (err <= 0)
|
| 1011 | return err;
|
| 1012 |
|
| 1013 | realfile = ovl_dir_real_file(file, true);
|
| 1014 | err = PTR_ERR_OR_ZERO(realfile);
|
| 1015 |
|
| 1016 |
|
| 1017 | if (!realfile || err)
|
| 1018 | return err;
|
| 1019 |
|
| 1020 | return vfs_fsync_range(realfile, start, end, datasync);
|
| 1021 | }
|
| 1022 |
|
| 1023 | static int ovl_dir_release(struct inode *inode, struct file *file)
|
| 1024 | {
|
| 1025 | struct ovl_dir_file *od = file->private_data;
|
| 1026 |
|
| 1027 | if (od->cache) {
|
| 1028 | inode_lock(inode);
|
| 1029 | ovl_cache_put(od, inode);
|
| 1030 | inode_unlock(inode);
|
| 1031 | }
|
| 1032 | fput(od->realfile);
|
| 1033 | if (od->upperfile)
|
| 1034 | fput(od->upperfile);
|
| 1035 | kfree(od);
|
| 1036 |
|
| 1037 | return 0;
|
| 1038 | }
|
| 1039 |
|
| 1040 | static int ovl_dir_open(struct inode *inode, struct file *file)
|
| 1041 | {
|
| 1042 | struct path realpath;
|
| 1043 | struct file *realfile;
|
| 1044 | struct ovl_dir_file *od;
|
| 1045 | enum ovl_path_type type;
|
| 1046 |
|
| 1047 | od = kzalloc_obj(struct ovl_dir_file);
|
| 1048 | if (!od)
|
| 1049 | return -ENOMEM;
|
| 1050 |
|
| 1051 | type = ovl_path_real(file->f_path.dentry, &realpath);
|
| 1052 | realfile = ovl_dir_open_realfile(file, &realpath);
|
| 1053 | if (IS_ERR(realfile)) {
|
| 1054 | kfree(od);
|
| 1055 | return PTR_ERR(realfile);
|
| 1056 | }
|
| 1057 | od->realfile = realfile;
|
| 1058 | od->is_real = ovl_dir_is_real(inode);
|
| 1059 | od->is_upper = OVL_TYPE_UPPER(type);
|
| 1060 | file->private_data = od;
|
| 1061 |
|
| 1062 | return 0;
|
| 1063 | }
|
| 1064 |
|
| 1065 | WRAP_DIR_ITER(ovl_iterate) |
| 1066 | const struct file_operations ovl_dir_operations = {
|
| 1067 | .read = generic_read_dir,
|
| 1068 | .open = ovl_dir_open,
|
| 1069 | .iterate_shared = shared_ovl_iterate,
|
| 1070 | .llseek = ovl_dir_llseek,
|
| 1071 | .fsync = ovl_dir_fsync,
|
| 1072 | .release = ovl_dir_release,
|
| 1073 | .setlease = generic_setlease,
|
| 1074 | };
|
| 1075 |
|
| 1076 | int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list)
|
| 1077 | {
|
| 1078 | int err;
|
| 1079 | struct ovl_cache_entry *p, *n;
|
| 1080 | struct rb_root root = RB_ROOT;
|
| 1081 |
|
| 1082 | with_ovl_creds(dentry->d_sb)
|
| 1083 | err = ovl_dir_read_merged(dentry, list, &root);
|
| 1084 | if (err)
|
| 1085 | return err;
|
| 1086 |
|
| 1087 | err = 0;
|
| 1088 |
|
| 1089 | list_for_each_entry_safe(p, n, list, l_node) {
|
| 1090 | |
| 1091 | * Select whiteouts in upperdir, they should
|
| 1092 | * be cleared when deleting this directory.
|
| 1093 |
|
| 1094 | if (p->is_whiteout) {
|
| 1095 | if (p->is_upper)
|
| 1096 | continue;
|
| 1097 | goto del_entry;
|
| 1098 | }
|
| 1099 |
|
| 1100 | if (name_is_dot_dotdot(p->name, p->len))
|
| 1101 | goto del_entry;
|
| 1102 | err = -ENOTEMPTY;
|
| 1103 | break;
|
| 1104 |
|
| 1105 | del_entry:
|
| 1106 | list_del(&p->l_node);
|
| 1107 | ovl_cache_entry_free(p);
|
| 1108 | }
|
| 1109 |
|
| 1110 | return err;
|
| 1111 | }
|
| 1112 |
|
| 1113 | void ovl_cleanup_whiteouts(struct ovl_fs *ofs, struct dentry *upper,
|
| 1114 | struct list_head *list)
|
| 1115 | {
|
| 1116 | struct ovl_cache_entry *p;
|
| 1117 |
|
| 1118 | list_for_each_entry(p, list, l_node) {
|
| 1119 | struct dentry *dentry;
|
| 1120 |
|
| 1121 | if (WARN_ON(!p->is_whiteout || !p->is_upper))
|
| 1122 | continue;
|
| 1123 |
|
| 1124 | dentry = ovl_lookup_upper_unlocked(ofs, p->name, upper, p->len);
|
| 1125 | if (IS_ERR(dentry)) {
|
| 1126 | pr_err("lookup '%s/%.*s' failed (%i)\n",
|
| 1127 | upper->d_name.name, p->len, p->name,
|
| 1128 | (int) PTR_ERR(dentry));
|
| 1129 | continue;
|
| 1130 | }
|
| 1131 | if (dentry->d_inode)
|
| 1132 | ovl_cleanup(ofs, upper, dentry);
|
| 1133 | dput(dentry);
|
| 1134 | }
|
| 1135 | }
|
| 1136 |
|
| 1137 | static bool ovl_check_d_type(struct dir_context *ctx, const char *name,
|
| 1138 | int namelen, loff_t offset, u64 ino,
|
| 1139 | unsigned int d_type)
|
| 1140 | {
|
| 1141 | struct ovl_readdir_data *rdd =
|
| 1142 | container_of(ctx, struct ovl_readdir_data, ctx);
|
| 1143 |
|
| 1144 |
|
| 1145 | if (name_is_dot_dotdot(name, namelen))
|
| 1146 | return true;
|
| 1147 |
|
| 1148 | if (d_type != DT_UNKNOWN)
|
| 1149 | rdd->d_type_supported = true;
|
| 1150 |
|
| 1151 | return true;
|
| 1152 | }
|
| 1153 |
|
| 1154 | |
| 1155 | * Returns 1 if d_type is supported, 0 not supported/unknown. Negative values
|
| 1156 | * if error is encountered.
|
| 1157 |
|
| 1158 | int ovl_check_d_type_supported(const struct path *realpath)
|
| 1159 | {
|
| 1160 | int err;
|
| 1161 | struct ovl_readdir_data rdd = {
|
| 1162 | .ctx.actor = ovl_check_d_type,
|
| 1163 | .ctx.count = INT_MAX,
|
| 1164 | .d_type_supported = false,
|
| 1165 | };
|
| 1166 |
|
| 1167 | err = ovl_dir_read(realpath, &rdd);
|
| 1168 | if (err)
|
| 1169 | return err;
|
| 1170 |
|
| 1171 | return rdd.d_type_supported;
|
| 1172 | }
|
| 1173 |
|
| 1174 | #define OVL_INCOMPATDIR_NAME "incompat"
|
| 1175 |
|
| 1176 | static int ovl_workdir_cleanup_recurse(struct ovl_fs *ofs, const struct path *path,
|
| 1177 | int level)
|
| 1178 | {
|
| 1179 | int err;
|
| 1180 | LIST_HEAD(list);
|
| 1181 | struct ovl_cache_entry *p;
|
| 1182 | struct ovl_readdir_data rdd = {
|
| 1183 | .ctx.actor = ovl_fill_plain,
|
| 1184 | .ctx.count = INT_MAX,
|
| 1185 | .list = &list,
|
| 1186 | };
|
| 1187 | bool incompat = false;
|
| 1188 |
|
| 1189 | |
| 1190 | * The "work/incompat" directory is treated specially - if it is not
|
| 1191 | * empty, instead of printing a generic error and mounting read-only,
|
| 1192 | * we will error about incompat features and fail the mount.
|
| 1193 | *
|
| 1194 | * When called from ovl_indexdir_cleanup(), path->dentry->d_name.name
|
| 1195 | * starts with '#'.
|
| 1196 |
|
| 1197 | if (level == 2 &&
|
| 1198 | !strcmp(path->dentry->d_name.name, OVL_INCOMPATDIR_NAME))
|
| 1199 | incompat = true;
|
| 1200 |
|
| 1201 | err = ovl_dir_read(path, &rdd);
|
| 1202 | if (err)
|
| 1203 | goto out;
|
| 1204 |
|
| 1205 | list_for_each_entry(p, &list, l_node) {
|
| 1206 | struct dentry *dentry;
|
| 1207 |
|
| 1208 | if (name_is_dot_dotdot(p->name, p->len)) {
|
| 1209 | continue;
|
| 1210 | } else if (incompat) {
|
| 1211 | pr_err("overlay with incompat feature '%s' cannot be mounted\n",
|
| 1212 | p->name);
|
| 1213 | err = -EINVAL;
|
| 1214 | break;
|
| 1215 | }
|
| 1216 | dentry = ovl_lookup_upper_unlocked(ofs, p->name, path->dentry, p->len);
|
| 1217 | if (IS_ERR(dentry))
|
| 1218 | continue;
|
| 1219 | if (dentry->d_inode)
|
| 1220 | err = ovl_workdir_cleanup(ofs, path->dentry, path->mnt,
|
| 1221 | dentry, level);
|
| 1222 | dput(dentry);
|
| 1223 | if (err)
|
| 1224 | break;
|
| 1225 | }
|
| 1226 | out:
|
| 1227 | ovl_cache_free(&list);
|
| 1228 | return err;
|
| 1229 | }
|
| 1230 |
|
| 1231 | int ovl_workdir_cleanup(struct ovl_fs *ofs, struct dentry *parent,
|
| 1232 | struct vfsmount *mnt, struct dentry *dentry, int level)
|
| 1233 | {
|
| 1234 | int err;
|
| 1235 |
|
| 1236 | if (!d_is_dir(dentry) || level > 1)
|
| 1237 | return ovl_cleanup(ofs, parent, dentry);
|
| 1238 |
|
| 1239 | dentry = start_removing_dentry(parent, dentry);
|
| 1240 | if (IS_ERR(dentry))
|
| 1241 | return PTR_ERR(dentry);
|
| 1242 | err = ovl_do_rmdir(ofs, parent->d_inode, dentry);
|
| 1243 | end_removing(dentry);
|
| 1244 | if (err) {
|
| 1245 | struct path path = { .mnt = mnt, .dentry = dentry };
|
| 1246 |
|
| 1247 | err = ovl_workdir_cleanup_recurse(ofs, &path, level + 1);
|
| 1248 | if (!err)
|
| 1249 | err = ovl_cleanup(ofs, parent, dentry);
|
| 1250 | }
|
| 1251 |
|
| 1252 | return err;
|
| 1253 | }
|
| 1254 |
|
| 1255 | int ovl_indexdir_cleanup(struct ovl_fs *ofs)
|
| 1256 | {
|
| 1257 | int err;
|
| 1258 | struct dentry *indexdir = ofs->workdir;
|
| 1259 | struct dentry *index = NULL;
|
| 1260 | struct path path = { .mnt = ovl_upper_mnt(ofs), .dentry = indexdir };
|
| 1261 | LIST_HEAD(list);
|
| 1262 | struct ovl_cache_entry *p;
|
| 1263 | struct ovl_readdir_data rdd = {
|
| 1264 | .ctx.actor = ovl_fill_plain,
|
| 1265 | .ctx.count = INT_MAX,
|
| 1266 | .list = &list,
|
| 1267 | };
|
| 1268 |
|
| 1269 | err = ovl_dir_read(&path, &rdd);
|
| 1270 | if (err)
|
| 1271 | goto out;
|
| 1272 |
|
| 1273 | list_for_each_entry(p, &list, l_node) {
|
| 1274 | if (name_is_dot_dotdot(p->name, p->len))
|
| 1275 | continue;
|
| 1276 | index = ovl_lookup_upper_unlocked(ofs, p->name, indexdir, p->len);
|
| 1277 | if (IS_ERR(index)) {
|
| 1278 | err = PTR_ERR(index);
|
| 1279 | index = NULL;
|
| 1280 | break;
|
| 1281 | }
|
| 1282 |
|
| 1283 | if (index->d_name.name[0] == '#') {
|
| 1284 | err = ovl_workdir_cleanup(ofs, indexdir, path.mnt, index, 1);
|
| 1285 | if (err)
|
| 1286 | break;
|
| 1287 | goto next;
|
| 1288 | }
|
| 1289 | err = ovl_verify_index(ofs, index);
|
| 1290 | if (!err) {
|
| 1291 | goto next;
|
| 1292 | } else if (err == -ESTALE) {
|
| 1293 |
|
| 1294 | err = ovl_cleanup(ofs, indexdir, index);
|
| 1295 | } else if (err != -ENOENT) {
|
| 1296 | |
| 1297 | * Abort mount to avoid corrupting the index if
|
| 1298 | * an incompatible index entry was found or on out
|
| 1299 | * of memory.
|
| 1300 |
|
| 1301 | break;
|
| 1302 | } else if (ofs->config.nfs_export) {
|
| 1303 | |
| 1304 | * Whiteout orphan index to block future open by
|
| 1305 | * handle after overlay nlink dropped to zero.
|
| 1306 |
|
| 1307 | err = ovl_cleanup_and_whiteout(ofs, indexdir, index);
|
| 1308 | } else {
|
| 1309 |
|
| 1310 | err = ovl_cleanup(ofs, indexdir, index);
|
| 1311 | }
|
| 1312 |
|
| 1313 | if (err)
|
| 1314 | break;
|
| 1315 |
|
| 1316 | next:
|
| 1317 | dput(index);
|
| 1318 | index = NULL;
|
| 1319 | }
|
| 1320 | dput(index);
|
| 1321 | out:
|
| 1322 | ovl_cache_free(&list);
|
| 1323 | if (err)
|
| 1324 | pr_err("failed index dir cleanup (%i)\n", err);
|
| 1325 | return err;
|
| 1326 | }
|