Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 1 | /* |
| 2 | * fs/sdcardfs/inode.c |
| 3 | * |
| 4 | * Copyright (c) 2013 Samsung Electronics Co. Ltd |
| 5 | * Authors: Daeho Jeong, Woojoong Lee, Seunghwan Hyun, |
| 6 | * Sunghwan Yun, Sungjong Seo |
| 7 | * |
| 8 | * This program has been developed as a stackable file system based on |
| 9 | * the WrapFS which written by |
| 10 | * |
| 11 | * Copyright (c) 1998-2011 Erez Zadok |
| 12 | * Copyright (c) 2009 Shrikar Archak |
| 13 | * Copyright (c) 2003-2011 Stony Brook University |
| 14 | * Copyright (c) 2003-2011 The Research Foundation of SUNY |
| 15 | * |
| 16 | * This file is dual licensed. It may be redistributed and/or modified |
| 17 | * under the terms of the Apache 2.0 License OR version 2 of the GNU |
| 18 | * General Public License. |
| 19 | */ |
| 20 | |
| 21 | #include "sdcardfs.h" |
Daniel Rosenberg | 2b31462 | 2016-04-13 16:38:34 -0700 | [diff] [blame] | 22 | #include <linux/fs_struct.h> |
Daniel Rosenberg | b434e57 | 2017-03-02 18:07:21 -0800 | [diff] [blame] | 23 | #include <linux/ratelimit.h> |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 24 | |
| 25 | /* Do not directly use this function. Use OVERRIDE_CRED() instead. */ |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 26 | const struct cred *override_fsids(struct sdcardfs_sb_info *sbi, struct sdcardfs_inode_info *info) |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 27 | { |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 28 | struct cred *cred; |
| 29 | const struct cred *old_cred; |
| 30 | uid_t uid; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 31 | |
| 32 | cred = prepare_creds(); |
| 33 | if (!cred) |
| 34 | return NULL; |
| 35 | |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 36 | if (info->under_obb) |
| 37 | uid = AID_MEDIA_OBB; |
| 38 | else |
| 39 | uid = multiuser_get_uid(info->userid, sbi->options.fs_low_uid); |
| 40 | cred->fsuid = make_kuid(&init_user_ns, uid); |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 41 | cred->fsgid = make_kgid(&init_user_ns, sbi->options.fs_low_gid); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 42 | |
| 43 | old_cred = override_creds(cred); |
| 44 | |
| 45 | return old_cred; |
| 46 | } |
| 47 | |
| 48 | /* Do not directly use this function, use REVERT_CRED() instead. */ |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 49 | void revert_fsids(const struct cred *old_cred) |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 50 | { |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 51 | const struct cred *cur_cred; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 52 | |
| 53 | cur_cred = current->cred; |
| 54 | revert_creds(old_cred); |
| 55 | put_cred(cur_cred); |
| 56 | } |
| 57 | |
| 58 | static int sdcardfs_create(struct inode *dir, struct dentry *dentry, |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 59 | umode_t mode, bool want_excl) |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 60 | { |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 61 | int err; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 62 | struct dentry *lower_dentry; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 63 | struct vfsmount *lower_dentry_mnt; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 64 | struct dentry *lower_parent_dentry = NULL; |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 65 | struct path lower_path; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 66 | const struct cred *saved_cred = NULL; |
Daniel Rosenberg | 2b31462 | 2016-04-13 16:38:34 -0700 | [diff] [blame] | 67 | struct fs_struct *saved_fs; |
| 68 | struct fs_struct *copied_fs; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 69 | |
Daniel Rosenberg | 5004c5f | 2017-01-31 20:07:51 -0800 | [diff] [blame] | 70 | if (!check_caller_access_to_name(dir, &dentry->d_name)) { |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 71 | err = -EACCES; |
| 72 | goto out_eacces; |
| 73 | } |
| 74 | |
| 75 | /* save current_cred and override it */ |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 76 | OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb), saved_cred, SDCARDFS_I(dir)); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 77 | |
| 78 | sdcardfs_get_lower_path(dentry, &lower_path); |
| 79 | lower_dentry = lower_path.dentry; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 80 | lower_dentry_mnt = lower_path.mnt; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 81 | lower_parent_dentry = lock_parent(lower_dentry); |
| 82 | |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 83 | /* set last 16bytes of mode field to 0664 */ |
| 84 | mode = (mode & S_IFMT) | 00664; |
Daniel Rosenberg | 2b31462 | 2016-04-13 16:38:34 -0700 | [diff] [blame] | 85 | |
| 86 | /* temporarily change umask for lower fs write */ |
| 87 | saved_fs = current->fs; |
| 88 | copied_fs = copy_fs_struct(current->fs); |
| 89 | if (!copied_fs) { |
| 90 | err = -ENOMEM; |
| 91 | goto out_unlock; |
| 92 | } |
| 93 | current->fs = copied_fs; |
| 94 | current->fs->umask = 0; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 95 | err = vfs_create2(lower_dentry_mnt, d_inode(lower_parent_dentry), lower_dentry, mode, want_excl); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 96 | if (err) |
| 97 | goto out; |
| 98 | |
Daniel Rosenberg | 497ac90 | 2016-02-03 21:08:21 -0800 | [diff] [blame] | 99 | err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path, SDCARDFS_I(dir)->userid); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 100 | if (err) |
| 101 | goto out; |
| 102 | fsstack_copy_attr_times(dir, sdcardfs_lower_inode(dir)); |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 103 | fsstack_copy_inode_size(dir, d_inode(lower_parent_dentry)); |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 104 | fixup_lower_ownership(dentry, dentry->d_name.name); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 105 | |
| 106 | out: |
Daniel Rosenberg | 2b31462 | 2016-04-13 16:38:34 -0700 | [diff] [blame] | 107 | current->fs = saved_fs; |
| 108 | free_fs_struct(copied_fs); |
| 109 | out_unlock: |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 110 | unlock_dir(lower_parent_dentry); |
| 111 | sdcardfs_put_lower_path(dentry, &lower_path); |
| 112 | REVERT_CRED(saved_cred); |
| 113 | out_eacces: |
| 114 | return err; |
| 115 | } |
| 116 | |
| 117 | #if 0 |
| 118 | static int sdcardfs_link(struct dentry *old_dentry, struct inode *dir, |
| 119 | struct dentry *new_dentry) |
| 120 | { |
| 121 | struct dentry *lower_old_dentry; |
| 122 | struct dentry *lower_new_dentry; |
| 123 | struct dentry *lower_dir_dentry; |
| 124 | u64 file_size_save; |
| 125 | int err; |
| 126 | struct path lower_old_path, lower_new_path; |
| 127 | |
| 128 | OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb)); |
| 129 | |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 130 | file_size_save = i_size_read(d_inode(old_dentry)); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 131 | sdcardfs_get_lower_path(old_dentry, &lower_old_path); |
| 132 | sdcardfs_get_lower_path(new_dentry, &lower_new_path); |
| 133 | lower_old_dentry = lower_old_path.dentry; |
| 134 | lower_new_dentry = lower_new_path.dentry; |
| 135 | lower_dir_dentry = lock_parent(lower_new_dentry); |
| 136 | |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 137 | err = vfs_link(lower_old_dentry, d_inode(lower_dir_dentry), |
| 138 | lower_new_dentry, NULL); |
| 139 | if (err || !d_inode(lower_new_dentry)) |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 140 | goto out; |
| 141 | |
| 142 | err = sdcardfs_interpose(new_dentry, dir->i_sb, &lower_new_path); |
| 143 | if (err) |
| 144 | goto out; |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 145 | fsstack_copy_attr_times(dir, d_inode(lower_new_dentry)); |
| 146 | fsstack_copy_inode_size(dir, d_inode(lower_new_dentry)); |
| 147 | set_nlink(d_inode(old_dentry), |
| 148 | sdcardfs_lower_inode(d_inode(old_dentry))->i_nlink); |
| 149 | i_size_write(d_inode(new_dentry), file_size_save); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 150 | out: |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 151 | unlock_dir(lower_dir_dentry); |
| 152 | sdcardfs_put_lower_path(old_dentry, &lower_old_path); |
| 153 | sdcardfs_put_lower_path(new_dentry, &lower_new_path); |
| 154 | REVERT_CRED(); |
| 155 | return err; |
| 156 | } |
| 157 | #endif |
| 158 | |
| 159 | static int sdcardfs_unlink(struct inode *dir, struct dentry *dentry) |
| 160 | { |
| 161 | int err; |
| 162 | struct dentry *lower_dentry; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 163 | struct vfsmount *lower_mnt; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 164 | struct inode *lower_dir_inode = sdcardfs_lower_inode(dir); |
| 165 | struct dentry *lower_dir_dentry; |
| 166 | struct path lower_path; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 167 | const struct cred *saved_cred = NULL; |
| 168 | |
Daniel Rosenberg | 5004c5f | 2017-01-31 20:07:51 -0800 | [diff] [blame] | 169 | if (!check_caller_access_to_name(dir, &dentry->d_name)) { |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 170 | err = -EACCES; |
| 171 | goto out_eacces; |
| 172 | } |
| 173 | |
| 174 | /* save current_cred and override it */ |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 175 | OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb), saved_cred, SDCARDFS_I(dir)); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 176 | |
| 177 | sdcardfs_get_lower_path(dentry, &lower_path); |
| 178 | lower_dentry = lower_path.dentry; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 179 | lower_mnt = lower_path.mnt; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 180 | dget(lower_dentry); |
| 181 | lower_dir_dentry = lock_parent(lower_dentry); |
| 182 | |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 183 | err = vfs_unlink2(lower_mnt, lower_dir_inode, lower_dentry, NULL); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 184 | |
| 185 | /* |
| 186 | * Note: unlinking on top of NFS can cause silly-renamed files. |
| 187 | * Trying to delete such files results in EBUSY from NFS |
| 188 | * below. Silly-renamed files will get deleted by NFS later on, so |
| 189 | * we just need to detect them here and treat such EBUSY errors as |
| 190 | * if the upper file was successfully deleted. |
| 191 | */ |
| 192 | if (err == -EBUSY && lower_dentry->d_flags & DCACHE_NFSFS_RENAMED) |
| 193 | err = 0; |
| 194 | if (err) |
| 195 | goto out; |
| 196 | fsstack_copy_attr_times(dir, lower_dir_inode); |
| 197 | fsstack_copy_inode_size(dir, lower_dir_inode); |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 198 | set_nlink(d_inode(dentry), |
| 199 | sdcardfs_lower_inode(d_inode(dentry))->i_nlink); |
| 200 | d_inode(dentry)->i_ctime = dir->i_ctime; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 201 | d_drop(dentry); /* this is needed, else LTP fails (VFS won't do it) */ |
| 202 | out: |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 203 | unlock_dir(lower_dir_dentry); |
| 204 | dput(lower_dentry); |
| 205 | sdcardfs_put_lower_path(dentry, &lower_path); |
| 206 | REVERT_CRED(saved_cred); |
| 207 | out_eacces: |
| 208 | return err; |
| 209 | } |
| 210 | |
| 211 | #if 0 |
| 212 | static int sdcardfs_symlink(struct inode *dir, struct dentry *dentry, |
| 213 | const char *symname) |
| 214 | { |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 215 | int err; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 216 | struct dentry *lower_dentry; |
| 217 | struct dentry *lower_parent_dentry = NULL; |
| 218 | struct path lower_path; |
| 219 | |
| 220 | OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb)); |
| 221 | |
| 222 | sdcardfs_get_lower_path(dentry, &lower_path); |
| 223 | lower_dentry = lower_path.dentry; |
| 224 | lower_parent_dentry = lock_parent(lower_dentry); |
| 225 | |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 226 | err = vfs_symlink(d_inode(lower_parent_dentry), lower_dentry, symname); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 227 | if (err) |
| 228 | goto out; |
| 229 | err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path); |
| 230 | if (err) |
| 231 | goto out; |
| 232 | fsstack_copy_attr_times(dir, sdcardfs_lower_inode(dir)); |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 233 | fsstack_copy_inode_size(dir, d_inode(lower_parent_dentry)); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 234 | |
| 235 | out: |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 236 | unlock_dir(lower_parent_dentry); |
| 237 | sdcardfs_put_lower_path(dentry, &lower_path); |
| 238 | REVERT_CRED(); |
| 239 | return err; |
| 240 | } |
| 241 | #endif |
| 242 | |
| 243 | static int touch(char *abs_path, mode_t mode) { |
| 244 | struct file *filp = filp_open(abs_path, O_RDWR|O_CREAT|O_EXCL|O_NOFOLLOW, mode); |
| 245 | if (IS_ERR(filp)) { |
| 246 | if (PTR_ERR(filp) == -EEXIST) { |
| 247 | return 0; |
| 248 | } |
| 249 | else { |
| 250 | printk(KERN_ERR "sdcardfs: failed to open(%s): %ld\n", |
| 251 | abs_path, PTR_ERR(filp)); |
| 252 | return PTR_ERR(filp); |
| 253 | } |
| 254 | } |
| 255 | filp_close(filp, current->files); |
| 256 | return 0; |
| 257 | } |
| 258 | |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 259 | static int sdcardfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 260 | { |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 261 | int err; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 262 | int make_nomedia_in_obb = 0; |
| 263 | struct dentry *lower_dentry; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 264 | struct vfsmount *lower_mnt; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 265 | struct dentry *lower_parent_dentry = NULL; |
| 266 | struct path lower_path; |
| 267 | struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb); |
| 268 | const struct cred *saved_cred = NULL; |
| 269 | struct sdcardfs_inode_info *pi = SDCARDFS_I(dir); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 270 | int touch_err = 0; |
Daniel Rosenberg | 2b31462 | 2016-04-13 16:38:34 -0700 | [diff] [blame] | 271 | struct fs_struct *saved_fs; |
| 272 | struct fs_struct *copied_fs; |
Daniel Rosenberg | 5004c5f | 2017-01-31 20:07:51 -0800 | [diff] [blame] | 273 | struct qstr q_obb = QSTR_LITERAL("obb"); |
| 274 | struct qstr q_data = QSTR_LITERAL("data"); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 275 | |
Daniel Rosenberg | 5004c5f | 2017-01-31 20:07:51 -0800 | [diff] [blame] | 276 | if (!check_caller_access_to_name(dir, &dentry->d_name)) { |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 277 | err = -EACCES; |
| 278 | goto out_eacces; |
| 279 | } |
| 280 | |
| 281 | /* save current_cred and override it */ |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 282 | OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb), saved_cred, SDCARDFS_I(dir)); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 283 | |
| 284 | /* check disk space */ |
| 285 | if (!check_min_free_space(dentry, 0, 1)) { |
| 286 | printk(KERN_INFO "sdcardfs: No minimum free space.\n"); |
| 287 | err = -ENOSPC; |
| 288 | goto out_revert; |
| 289 | } |
| 290 | |
| 291 | /* the lower_dentry is negative here */ |
| 292 | sdcardfs_get_lower_path(dentry, &lower_path); |
| 293 | lower_dentry = lower_path.dentry; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 294 | lower_mnt = lower_path.mnt; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 295 | lower_parent_dentry = lock_parent(lower_dentry); |
| 296 | |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 297 | /* set last 16bytes of mode field to 0775 */ |
| 298 | mode = (mode & S_IFMT) | 00775; |
Daniel Rosenberg | 2b31462 | 2016-04-13 16:38:34 -0700 | [diff] [blame] | 299 | |
| 300 | /* temporarily change umask for lower fs write */ |
| 301 | saved_fs = current->fs; |
| 302 | copied_fs = copy_fs_struct(current->fs); |
| 303 | if (!copied_fs) { |
| 304 | err = -ENOMEM; |
Daniel Rosenberg | 9480415 | 2016-09-26 14:48:22 -0700 | [diff] [blame] | 305 | unlock_dir(lower_parent_dentry); |
Daniel Rosenberg | 2b31462 | 2016-04-13 16:38:34 -0700 | [diff] [blame] | 306 | goto out_unlock; |
| 307 | } |
| 308 | current->fs = copied_fs; |
| 309 | current->fs->umask = 0; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 310 | err = vfs_mkdir2(lower_mnt, d_inode(lower_parent_dentry), lower_dentry, mode); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 311 | |
Daniel Rosenberg | 9480415 | 2016-09-26 14:48:22 -0700 | [diff] [blame] | 312 | if (err) { |
| 313 | unlock_dir(lower_parent_dentry); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 314 | goto out; |
Daniel Rosenberg | 9480415 | 2016-09-26 14:48:22 -0700 | [diff] [blame] | 315 | } |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 316 | |
| 317 | /* if it is a local obb dentry, setup it with the base obbpath */ |
| 318 | if(need_graft_path(dentry)) { |
| 319 | |
| 320 | err = setup_obb_dentry(dentry, &lower_path); |
| 321 | if(err) { |
| 322 | /* if the sbi->obbpath is not available, the lower_path won't be |
| 323 | * changed by setup_obb_dentry() but the lower path is saved to |
Daniel Rosenberg | 497ac90 | 2016-02-03 21:08:21 -0800 | [diff] [blame] | 324 | * its orig_path. this dentry will be revalidated later. |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 325 | * but now, the lower_path should be NULL */ |
| 326 | sdcardfs_put_reset_lower_path(dentry); |
| 327 | |
| 328 | /* the newly created lower path which saved to its orig_path or |
| 329 | * the lower_path is the base obbpath. |
Daniel Rosenberg | 497ac90 | 2016-02-03 21:08:21 -0800 | [diff] [blame] | 330 | * therefore, an additional path_get is required */ |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 331 | path_get(&lower_path); |
| 332 | } else |
| 333 | make_nomedia_in_obb = 1; |
| 334 | } |
| 335 | |
Daniel Rosenberg | 497ac90 | 2016-02-03 21:08:21 -0800 | [diff] [blame] | 336 | err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path, pi->userid); |
Daniel Rosenberg | 9480415 | 2016-09-26 14:48:22 -0700 | [diff] [blame] | 337 | if (err) { |
| 338 | unlock_dir(lower_parent_dentry); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 339 | goto out; |
Daniel Rosenberg | 9480415 | 2016-09-26 14:48:22 -0700 | [diff] [blame] | 340 | } |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 341 | |
| 342 | fsstack_copy_attr_times(dir, sdcardfs_lower_inode(dir)); |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 343 | fsstack_copy_inode_size(dir, d_inode(lower_parent_dentry)); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 344 | /* update number of links on parent directory */ |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 345 | set_nlink(dir, sdcardfs_lower_inode(dir)->i_nlink); |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 346 | fixup_lower_ownership(dentry, dentry->d_name.name); |
Daniel Rosenberg | 9480415 | 2016-09-26 14:48:22 -0700 | [diff] [blame] | 347 | unlock_dir(lower_parent_dentry); |
Daniel Rosenberg | 5004c5f | 2017-01-31 20:07:51 -0800 | [diff] [blame] | 348 | if ((!sbi->options.multiuser) && (qstr_case_eq(&dentry->d_name, &q_obb)) |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 349 | && (pi->perm == PERM_ANDROID) && (pi->userid == 0)) |
| 350 | make_nomedia_in_obb = 1; |
| 351 | |
| 352 | /* When creating /Android/data and /Android/obb, mark them as .nomedia */ |
| 353 | if (make_nomedia_in_obb || |
Daniel Rosenberg | 5004c5f | 2017-01-31 20:07:51 -0800 | [diff] [blame] | 354 | ((pi->perm == PERM_ANDROID) && (qstr_case_eq(&dentry->d_name, &q_data)))) { |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 355 | REVERT_CRED(saved_cred); |
| 356 | OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb), saved_cred, SDCARDFS_I(d_inode(dentry))); |
Daniel Rosenberg | 2b31462 | 2016-04-13 16:38:34 -0700 | [diff] [blame] | 357 | set_fs_pwd(current->fs, &lower_path); |
| 358 | touch_err = touch(".nomedia", 0664); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 359 | if (touch_err) { |
Daniel Rosenberg | 2b31462 | 2016-04-13 16:38:34 -0700 | [diff] [blame] | 360 | printk(KERN_ERR "sdcardfs: failed to create .nomedia in %s: %d\n", |
| 361 | lower_path.dentry->d_name.name, touch_err); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 362 | goto out; |
| 363 | } |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 364 | } |
| 365 | out: |
Daniel Rosenberg | 2b31462 | 2016-04-13 16:38:34 -0700 | [diff] [blame] | 366 | current->fs = saved_fs; |
| 367 | free_fs_struct(copied_fs); |
| 368 | out_unlock: |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 369 | sdcardfs_put_lower_path(dentry, &lower_path); |
| 370 | out_revert: |
| 371 | REVERT_CRED(saved_cred); |
| 372 | out_eacces: |
| 373 | return err; |
| 374 | } |
| 375 | |
| 376 | static int sdcardfs_rmdir(struct inode *dir, struct dentry *dentry) |
| 377 | { |
| 378 | struct dentry *lower_dentry; |
| 379 | struct dentry *lower_dir_dentry; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 380 | struct vfsmount *lower_mnt; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 381 | int err; |
| 382 | struct path lower_path; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 383 | const struct cred *saved_cred = NULL; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 384 | |
Daniel Rosenberg | 5004c5f | 2017-01-31 20:07:51 -0800 | [diff] [blame] | 385 | if (!check_caller_access_to_name(dir, &dentry->d_name)) { |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 386 | err = -EACCES; |
| 387 | goto out_eacces; |
| 388 | } |
| 389 | |
| 390 | /* save current_cred and override it */ |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 391 | OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb), saved_cred, SDCARDFS_I(dir)); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 392 | |
| 393 | /* sdcardfs_get_real_lower(): in case of remove an user's obb dentry |
| 394 | * the dentry on the original path should be deleted. */ |
| 395 | sdcardfs_get_real_lower(dentry, &lower_path); |
| 396 | |
| 397 | lower_dentry = lower_path.dentry; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 398 | lower_mnt = lower_path.mnt; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 399 | lower_dir_dentry = lock_parent(lower_dentry); |
| 400 | |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 401 | err = vfs_rmdir2(lower_mnt, d_inode(lower_dir_dentry), lower_dentry); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 402 | if (err) |
| 403 | goto out; |
| 404 | |
| 405 | d_drop(dentry); /* drop our dentry on success (why not VFS's job?) */ |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 406 | if (d_inode(dentry)) |
| 407 | clear_nlink(d_inode(dentry)); |
| 408 | fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry)); |
| 409 | fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry)); |
| 410 | set_nlink(dir, d_inode(lower_dir_dentry)->i_nlink); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 411 | |
| 412 | out: |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 413 | unlock_dir(lower_dir_dentry); |
| 414 | sdcardfs_put_real_lower(dentry, &lower_path); |
| 415 | REVERT_CRED(saved_cred); |
| 416 | out_eacces: |
| 417 | return err; |
| 418 | } |
| 419 | |
| 420 | #if 0 |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 421 | static int sdcardfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 422 | dev_t dev) |
| 423 | { |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 424 | int err; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 425 | struct dentry *lower_dentry; |
| 426 | struct dentry *lower_parent_dentry = NULL; |
| 427 | struct path lower_path; |
| 428 | |
| 429 | OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb)); |
| 430 | |
| 431 | sdcardfs_get_lower_path(dentry, &lower_path); |
| 432 | lower_dentry = lower_path.dentry; |
| 433 | lower_parent_dentry = lock_parent(lower_dentry); |
| 434 | |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 435 | err = vfs_mknod(d_inode(lower_parent_dentry), lower_dentry, mode, dev); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 436 | if (err) |
| 437 | goto out; |
| 438 | |
| 439 | err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path); |
| 440 | if (err) |
| 441 | goto out; |
| 442 | fsstack_copy_attr_times(dir, sdcardfs_lower_inode(dir)); |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 443 | fsstack_copy_inode_size(dir, d_inode(lower_parent_dentry)); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 444 | |
| 445 | out: |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 446 | unlock_dir(lower_parent_dentry); |
| 447 | sdcardfs_put_lower_path(dentry, &lower_path); |
| 448 | REVERT_CRED(); |
| 449 | return err; |
| 450 | } |
| 451 | #endif |
| 452 | |
| 453 | /* |
| 454 | * The locking rules in sdcardfs_rename are complex. We could use a simpler |
| 455 | * superblock-level name-space lock for renames and copy-ups. |
| 456 | */ |
| 457 | static int sdcardfs_rename(struct inode *old_dir, struct dentry *old_dentry, |
Amit Pundir | d4ae31b | 2016-10-16 15:24:15 +0530 | [diff] [blame] | 458 | struct inode *new_dir, struct dentry *new_dentry, |
| 459 | unsigned int flags) |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 460 | { |
| 461 | int err = 0; |
| 462 | struct dentry *lower_old_dentry = NULL; |
| 463 | struct dentry *lower_new_dentry = NULL; |
| 464 | struct dentry *lower_old_dir_dentry = NULL; |
| 465 | struct dentry *lower_new_dir_dentry = NULL; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 466 | struct vfsmount *lower_mnt = NULL; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 467 | struct dentry *trap = NULL; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 468 | struct path lower_old_path, lower_new_path; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 469 | const struct cred *saved_cred = NULL; |
| 470 | |
Amit Pundir | d4ae31b | 2016-10-16 15:24:15 +0530 | [diff] [blame] | 471 | if (flags) |
| 472 | return -EINVAL; |
| 473 | |
Daniel Rosenberg | 5004c5f | 2017-01-31 20:07:51 -0800 | [diff] [blame] | 474 | if (!check_caller_access_to_name(old_dir, &old_dentry->d_name) || |
| 475 | !check_caller_access_to_name(new_dir, &new_dentry->d_name)) { |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 476 | err = -EACCES; |
| 477 | goto out_eacces; |
| 478 | } |
| 479 | |
| 480 | /* save current_cred and override it */ |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 481 | OVERRIDE_CRED(SDCARDFS_SB(old_dir->i_sb), saved_cred, SDCARDFS_I(new_dir)); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 482 | |
| 483 | sdcardfs_get_real_lower(old_dentry, &lower_old_path); |
| 484 | sdcardfs_get_lower_path(new_dentry, &lower_new_path); |
| 485 | lower_old_dentry = lower_old_path.dentry; |
| 486 | lower_new_dentry = lower_new_path.dentry; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 487 | lower_mnt = lower_old_path.mnt; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 488 | lower_old_dir_dentry = dget_parent(lower_old_dentry); |
| 489 | lower_new_dir_dentry = dget_parent(lower_new_dentry); |
| 490 | |
| 491 | trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry); |
| 492 | /* source should not be ancestor of target */ |
| 493 | if (trap == lower_old_dentry) { |
| 494 | err = -EINVAL; |
| 495 | goto out; |
| 496 | } |
| 497 | /* target should not be ancestor of source */ |
| 498 | if (trap == lower_new_dentry) { |
| 499 | err = -ENOTEMPTY; |
| 500 | goto out; |
| 501 | } |
| 502 | |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 503 | err = vfs_rename2(lower_mnt, |
| 504 | d_inode(lower_old_dir_dentry), lower_old_dentry, |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 505 | d_inode(lower_new_dir_dentry), lower_new_dentry, |
| 506 | NULL, 0); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 507 | if (err) |
| 508 | goto out; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 509 | |
| 510 | /* Copy attrs from lower dir, but i_uid/i_gid */ |
Daniel Rosenberg | 497ac90 | 2016-02-03 21:08:21 -0800 | [diff] [blame] | 511 | sdcardfs_copy_and_fix_attrs(new_dir, d_inode(lower_new_dir_dentry)); |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 512 | fsstack_copy_inode_size(new_dir, d_inode(lower_new_dir_dentry)); |
Daniel Rosenberg | 497ac90 | 2016-02-03 21:08:21 -0800 | [diff] [blame] | 513 | |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 514 | if (new_dir != old_dir) { |
Daniel Rosenberg | 497ac90 | 2016-02-03 21:08:21 -0800 | [diff] [blame] | 515 | sdcardfs_copy_and_fix_attrs(old_dir, d_inode(lower_old_dir_dentry)); |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 516 | fsstack_copy_inode_size(old_dir, d_inode(lower_old_dir_dentry)); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 517 | } |
Daniel Rosenberg | 5004c5f | 2017-01-31 20:07:51 -0800 | [diff] [blame] | 518 | get_derived_permission_new(new_dentry->d_parent, old_dentry, &new_dentry->d_name); |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 519 | fixup_tmp_permissions(d_inode(old_dentry)); |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 520 | fixup_lower_ownership(old_dentry, new_dentry->d_name.name); |
Daniel Rosenberg | 64386ed | 2017-03-08 17:45:46 -0800 | [diff] [blame] | 521 | d_invalidate(old_dentry); /* Can't fixup ownership recursively :( */ |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 522 | out: |
| 523 | unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry); |
| 524 | dput(lower_old_dir_dentry); |
| 525 | dput(lower_new_dir_dentry); |
| 526 | sdcardfs_put_real_lower(old_dentry, &lower_old_path); |
| 527 | sdcardfs_put_lower_path(new_dentry, &lower_new_path); |
| 528 | REVERT_CRED(saved_cred); |
| 529 | out_eacces: |
| 530 | return err; |
| 531 | } |
| 532 | |
| 533 | #if 0 |
| 534 | static int sdcardfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz) |
| 535 | { |
| 536 | int err; |
| 537 | struct dentry *lower_dentry; |
| 538 | struct path lower_path; |
| 539 | /* XXX readlink does not requires overriding credential */ |
| 540 | |
| 541 | sdcardfs_get_lower_path(dentry, &lower_path); |
| 542 | lower_dentry = lower_path.dentry; |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 543 | if (!d_inode(lower_dentry)->i_op || |
| 544 | !d_inode(lower_dentry)->i_op->readlink) { |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 545 | err = -EINVAL; |
| 546 | goto out; |
| 547 | } |
| 548 | |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 549 | err = d_inode(lower_dentry)->i_op->readlink(lower_dentry, |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 550 | buf, bufsiz); |
| 551 | if (err < 0) |
| 552 | goto out; |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 553 | fsstack_copy_attr_atime(d_inode(dentry), d_inode(lower_dentry)); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 554 | |
| 555 | out: |
| 556 | sdcardfs_put_lower_path(dentry, &lower_path); |
| 557 | return err; |
| 558 | } |
| 559 | #endif |
| 560 | |
| 561 | #if 0 |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 562 | static const char *sdcardfs_follow_link(struct dentry *dentry, void **cookie) |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 563 | { |
| 564 | char *buf; |
| 565 | int len = PAGE_SIZE, err; |
| 566 | mm_segment_t old_fs; |
| 567 | |
| 568 | /* This is freed by the put_link method assuming a successful call. */ |
| 569 | buf = kmalloc(len, GFP_KERNEL); |
| 570 | if (!buf) { |
| 571 | buf = ERR_PTR(-ENOMEM); |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 572 | return buf; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 573 | } |
| 574 | |
| 575 | /* read the symlink, and then we will follow it */ |
| 576 | old_fs = get_fs(); |
| 577 | set_fs(KERNEL_DS); |
| 578 | err = sdcardfs_readlink(dentry, buf, len); |
| 579 | set_fs(old_fs); |
| 580 | if (err < 0) { |
| 581 | kfree(buf); |
| 582 | buf = ERR_PTR(err); |
| 583 | } else { |
| 584 | buf[err] = '\0'; |
| 585 | } |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 586 | return *cookie = buf; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 587 | } |
| 588 | #endif |
| 589 | |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 590 | static int sdcardfs_permission_wrn(struct inode *inode, int mask) |
| 591 | { |
Daniel Rosenberg | b434e57 | 2017-03-02 18:07:21 -0800 | [diff] [blame] | 592 | WARN_RATELIMIT(1, "sdcardfs does not support permission. Use permission2.\n"); |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 593 | return -EINVAL; |
| 594 | } |
| 595 | |
| 596 | void copy_attrs(struct inode *dest, const struct inode *src) |
| 597 | { |
| 598 | dest->i_mode = src->i_mode; |
| 599 | dest->i_uid = src->i_uid; |
| 600 | dest->i_gid = src->i_gid; |
| 601 | dest->i_rdev = src->i_rdev; |
| 602 | dest->i_atime = src->i_atime; |
| 603 | dest->i_mtime = src->i_mtime; |
| 604 | dest->i_ctime = src->i_ctime; |
| 605 | dest->i_blkbits = src->i_blkbits; |
| 606 | dest->i_flags = src->i_flags; |
| 607 | #ifdef CONFIG_FS_POSIX_ACL |
| 608 | dest->i_acl = src->i_acl; |
| 609 | #endif |
| 610 | #ifdef CONFIG_SECURITY |
| 611 | dest->i_security = src->i_security; |
| 612 | #endif |
| 613 | } |
| 614 | |
| 615 | static int sdcardfs_permission(struct vfsmount *mnt, struct inode *inode, int mask) |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 616 | { |
| 617 | int err; |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 618 | struct inode tmp; |
Daniel Rosenberg | 5080d24 | 2016-05-18 16:57:10 -0700 | [diff] [blame] | 619 | struct inode *top = grab_top(SDCARDFS_I(inode)); |
| 620 | |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 621 | if (!top) { |
| 622 | release_top(SDCARDFS_I(inode)); |
| 623 | WARN(1, "Top value was null!\n"); |
Daniel Rosenberg | 5080d24 | 2016-05-18 16:57:10 -0700 | [diff] [blame] | 624 | return -EINVAL; |
Daniel Rosenberg | 5080d24 | 2016-05-18 16:57:10 -0700 | [diff] [blame] | 625 | } |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 626 | |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 627 | /* |
| 628 | * Permission check on sdcardfs inode. |
| 629 | * Calling process should have AID_SDCARD_RW permission |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 630 | * Since generic_permission only needs i_mode, i_uid, |
| 631 | * i_gid, and i_sb, we can create a fake inode to pass |
| 632 | * this information down in. |
| 633 | * |
| 634 | * The underlying code may attempt to take locks in some |
| 635 | * cases for features we're not using, but if that changes, |
| 636 | * locks must be dealt with to avoid undefined behavior. |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 637 | */ |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 638 | copy_attrs(&tmp, inode); |
| 639 | tmp.i_uid = make_kuid(&init_user_ns, SDCARDFS_I(top)->d_uid); |
| 640 | tmp.i_gid = make_kgid(&init_user_ns, get_gid(mnt, SDCARDFS_I(top))); |
| 641 | tmp.i_mode = (inode->i_mode & S_IFMT) | get_mode(mnt, SDCARDFS_I(top)); |
| 642 | release_top(SDCARDFS_I(inode)); |
| 643 | tmp.i_sb = inode->i_sb; |
| 644 | if (IS_POSIXACL(inode)) |
| 645 | printk(KERN_WARNING "%s: This may be undefined behavior... \n", __func__); |
| 646 | err = generic_permission(&tmp, mask); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 647 | /* XXX |
| 648 | * Original sdcardfs code calls inode_permission(lower_inode,.. ) |
| 649 | * for checking inode permission. But doing such things here seems |
| 650 | * duplicated work, because the functions called after this func, |
| 651 | * such as vfs_create, vfs_unlink, vfs_rename, and etc, |
| 652 | * does exactly same thing, i.e., they calls inode_permission(). |
| 653 | * So we just let they do the things. |
| 654 | * If there are any security hole, just uncomment following if block. |
| 655 | */ |
| 656 | #if 0 |
| 657 | if (!err) { |
| 658 | /* |
| 659 | * Permission check on lower_inode(=EXT4). |
| 660 | * we check it with AID_MEDIA_RW permission |
| 661 | */ |
| 662 | struct inode *lower_inode; |
| 663 | OVERRIDE_CRED(SDCARDFS_SB(inode->sb)); |
| 664 | |
| 665 | lower_inode = sdcardfs_lower_inode(inode); |
| 666 | err = inode_permission(lower_inode, mask); |
| 667 | |
| 668 | REVERT_CRED(); |
| 669 | } |
| 670 | #endif |
| 671 | return err; |
| 672 | |
| 673 | } |
| 674 | |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 675 | static int sdcardfs_setattr_wrn(struct dentry *dentry, struct iattr *ia) |
| 676 | { |
Daniel Rosenberg | b434e57 | 2017-03-02 18:07:21 -0800 | [diff] [blame] | 677 | WARN_RATELIMIT(1, "sdcardfs does not support setattr. User setattr2.\n"); |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 678 | return -EINVAL; |
| 679 | } |
| 680 | |
| 681 | static int sdcardfs_setattr(struct vfsmount *mnt, struct dentry *dentry, struct iattr *ia) |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 682 | { |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 683 | int err; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 684 | struct dentry *lower_dentry; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 685 | struct vfsmount *lower_mnt; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 686 | struct inode *inode; |
| 687 | struct inode *lower_inode; |
| 688 | struct path lower_path; |
| 689 | struct iattr lower_ia; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 690 | struct dentry *parent; |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 691 | struct inode tmp; |
Amit Pundir | 82a2800 | 2016-10-11 13:26:17 +0530 | [diff] [blame] | 692 | struct dentry tmp_d; |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 693 | struct inode *top; |
| 694 | const struct cred *saved_cred = NULL; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 695 | |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 696 | inode = d_inode(dentry); |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 697 | top = grab_top(SDCARDFS_I(inode)); |
| 698 | |
| 699 | if (!top) { |
| 700 | release_top(SDCARDFS_I(inode)); |
| 701 | return -EINVAL; |
| 702 | } |
| 703 | |
| 704 | /* |
| 705 | * Permission check on sdcardfs inode. |
| 706 | * Calling process should have AID_SDCARD_RW permission |
| 707 | * Since generic_permission only needs i_mode, i_uid, |
| 708 | * i_gid, and i_sb, we can create a fake inode to pass |
| 709 | * this information down in. |
| 710 | * |
| 711 | * The underlying code may attempt to take locks in some |
| 712 | * cases for features we're not using, but if that changes, |
| 713 | * locks must be dealt with to avoid undefined behavior. |
| 714 | * |
| 715 | */ |
| 716 | copy_attrs(&tmp, inode); |
| 717 | tmp.i_uid = make_kuid(&init_user_ns, SDCARDFS_I(top)->d_uid); |
| 718 | tmp.i_gid = make_kgid(&init_user_ns, get_gid(mnt, SDCARDFS_I(top))); |
| 719 | tmp.i_mode = (inode->i_mode & S_IFMT) | get_mode(mnt, SDCARDFS_I(top)); |
| 720 | tmp.i_size = i_size_read(inode); |
| 721 | release_top(SDCARDFS_I(inode)); |
| 722 | tmp.i_sb = inode->i_sb; |
Amit Pundir | 82a2800 | 2016-10-11 13:26:17 +0530 | [diff] [blame] | 723 | tmp_d.d_inode = &tmp; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 724 | |
| 725 | /* |
Amit Pundir | 82a2800 | 2016-10-11 13:26:17 +0530 | [diff] [blame] | 726 | * Check if user has permission to change dentry. We don't check if |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 727 | * this user can change the lower inode: that should happen when |
| 728 | * calling notify_change on the lower inode. |
| 729 | */ |
Daniel Rosenberg | 83d1cad | 2017-01-20 15:19:13 -0800 | [diff] [blame] | 730 | /* prepare our own lower struct iattr (with the lower file) */ |
| 731 | memcpy(&lower_ia, ia, sizeof(lower_ia)); |
| 732 | /* Allow touch updating timestamps. A previous permission check ensures |
| 733 | * we have write access. Changes to mode, owner, and group are ignored*/ |
| 734 | ia->ia_valid |= ATTR_FORCE; |
Amit Pundir | 82a2800 | 2016-10-11 13:26:17 +0530 | [diff] [blame] | 735 | err = setattr_prepare(&tmp_d, ia); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 736 | |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 737 | if (!err) { |
| 738 | /* check the Android group ID */ |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 739 | parent = dget_parent(dentry); |
Daniel Rosenberg | 32dc587 | 2017-03-10 18:58:25 -0800 | [diff] [blame^] | 740 | if (!check_caller_access_to_name(d_inode(parent), &dentry->d_name)) |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 741 | err = -EACCES; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 742 | dput(parent); |
| 743 | } |
| 744 | |
| 745 | if (err) |
| 746 | goto out_err; |
| 747 | |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 748 | /* save current_cred and override it */ |
Daniel Rosenberg | ad90525 | 2017-01-25 13:48:45 -0800 | [diff] [blame] | 749 | OVERRIDE_CRED(SDCARDFS_SB(dentry->d_sb), saved_cred, SDCARDFS_I(inode)); |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 750 | |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 751 | sdcardfs_get_lower_path(dentry, &lower_path); |
| 752 | lower_dentry = lower_path.dentry; |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 753 | lower_mnt = lower_path.mnt; |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 754 | lower_inode = sdcardfs_lower_inode(inode); |
| 755 | |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 756 | if (ia->ia_valid & ATTR_FILE) |
| 757 | lower_ia.ia_file = sdcardfs_lower_file(ia->ia_file); |
| 758 | |
| 759 | lower_ia.ia_valid &= ~(ATTR_UID | ATTR_GID | ATTR_MODE); |
| 760 | |
| 761 | /* |
| 762 | * If shrinking, first truncate upper level to cancel writing dirty |
| 763 | * pages beyond the new eof; and also if its' maxbytes is more |
| 764 | * limiting (fail with -EFBIG before making any change to the lower |
| 765 | * level). There is no need to vmtruncate the upper level |
| 766 | * afterwards in the other cases: we fsstack_copy_inode_size from |
| 767 | * the lower level. |
| 768 | */ |
| 769 | if (current->mm) |
| 770 | down_write(¤t->mm->mmap_sem); |
| 771 | if (ia->ia_valid & ATTR_SIZE) { |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 772 | err = inode_newsize_ok(&tmp, ia->ia_size); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 773 | if (err) { |
| 774 | if (current->mm) |
| 775 | up_write(¤t->mm->mmap_sem); |
| 776 | goto out; |
| 777 | } |
| 778 | truncate_setsize(inode, ia->ia_size); |
| 779 | } |
| 780 | |
| 781 | /* |
| 782 | * mode change is for clearing setuid/setgid bits. Allow lower fs |
| 783 | * to interpret this in its own way. |
| 784 | */ |
| 785 | if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID)) |
| 786 | lower_ia.ia_valid &= ~ATTR_MODE; |
| 787 | |
| 788 | /* notify the (possibly copied-up) lower inode */ |
| 789 | /* |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 790 | * Note: we use d_inode(lower_dentry), because lower_inode may be |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 791 | * unlinked (no inode->i_sb and i_ino==0. This happens if someone |
| 792 | * tries to open(), unlink(), then ftruncate() a file. |
| 793 | */ |
Amit Pundir | b47e110 | 2016-06-01 21:53:20 +0530 | [diff] [blame] | 794 | inode_lock(d_inode(lower_dentry)); |
Daniel Rosenberg | 1844d9e | 2016-10-26 16:48:45 -0700 | [diff] [blame] | 795 | err = notify_change2(lower_mnt, lower_dentry, &lower_ia, /* note: lower_ia */ |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 796 | NULL); |
Amit Pundir | b47e110 | 2016-06-01 21:53:20 +0530 | [diff] [blame] | 797 | inode_unlock(d_inode(lower_dentry)); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 798 | if (current->mm) |
| 799 | up_write(¤t->mm->mmap_sem); |
| 800 | if (err) |
| 801 | goto out; |
| 802 | |
Daniel Rosenberg | 497ac90 | 2016-02-03 21:08:21 -0800 | [diff] [blame] | 803 | /* get attributes from the lower inode and update derived permissions */ |
| 804 | sdcardfs_copy_and_fix_attrs(inode, lower_inode); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 805 | |
| 806 | /* |
| 807 | * Not running fsstack_copy_inode_size(inode, lower_inode), because |
| 808 | * VFS should update our inode size, and notify_change on |
| 809 | * lower_inode should update its size. |
| 810 | */ |
| 811 | |
| 812 | out: |
| 813 | sdcardfs_put_lower_path(dentry, &lower_path); |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 814 | REVERT_CRED(saved_cred); |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 815 | out_err: |
| 816 | return err; |
| 817 | } |
| 818 | |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 819 | static int sdcardfs_fillattr(struct vfsmount *mnt, struct inode *inode, struct kstat *stat) |
Daniel Rosenberg | 5080d24 | 2016-05-18 16:57:10 -0700 | [diff] [blame] | 820 | { |
| 821 | struct sdcardfs_inode_info *info = SDCARDFS_I(inode); |
| 822 | struct inode *top = grab_top(info); |
| 823 | if (!top) |
| 824 | return -EINVAL; |
| 825 | |
| 826 | stat->dev = inode->i_sb->s_dev; |
| 827 | stat->ino = inode->i_ino; |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 828 | stat->mode = (inode->i_mode & S_IFMT) | get_mode(mnt, SDCARDFS_I(top)); |
Daniel Rosenberg | 5080d24 | 2016-05-18 16:57:10 -0700 | [diff] [blame] | 829 | stat->nlink = inode->i_nlink; |
| 830 | stat->uid = make_kuid(&init_user_ns, SDCARDFS_I(top)->d_uid); |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 831 | stat->gid = make_kgid(&init_user_ns, get_gid(mnt, SDCARDFS_I(top))); |
Daniel Rosenberg | 5080d24 | 2016-05-18 16:57:10 -0700 | [diff] [blame] | 832 | stat->rdev = inode->i_rdev; |
| 833 | stat->size = i_size_read(inode); |
| 834 | stat->atime = inode->i_atime; |
| 835 | stat->mtime = inode->i_mtime; |
| 836 | stat->ctime = inode->i_ctime; |
| 837 | stat->blksize = (1 << inode->i_blkbits); |
| 838 | stat->blocks = inode->i_blocks; |
| 839 | release_top(info); |
| 840 | return 0; |
| 841 | } |
| 842 | |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 843 | static int sdcardfs_getattr(struct vfsmount *mnt, struct dentry *dentry, |
| 844 | struct kstat *stat) |
| 845 | { |
Daniel Rosenberg | 3884c2e | 2017-03-09 18:12:16 -0800 | [diff] [blame] | 846 | struct kstat lower_stat; |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 847 | struct path lower_path; |
| 848 | struct dentry *parent; |
Daniel Rosenberg | 5080d24 | 2016-05-18 16:57:10 -0700 | [diff] [blame] | 849 | int err; |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 850 | |
| 851 | parent = dget_parent(dentry); |
Daniel Rosenberg | 5004c5f | 2017-01-31 20:07:51 -0800 | [diff] [blame] | 852 | if (!check_caller_access_to_name(d_inode(parent), &dentry->d_name)) { |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 853 | dput(parent); |
| 854 | return -EACCES; |
| 855 | } |
| 856 | dput(parent); |
| 857 | |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 858 | sdcardfs_get_lower_path(dentry, &lower_path); |
Daniel Rosenberg | 3884c2e | 2017-03-09 18:12:16 -0800 | [diff] [blame] | 859 | err = vfs_getattr(&lower_path, &lower_stat); |
| 860 | if (err) |
| 861 | goto out; |
| 862 | sdcardfs_copy_and_fix_attrs(d_inode(dentry), |
| 863 | d_inode(lower_path.dentry)); |
| 864 | err = sdcardfs_fillattr(mnt, d_inode(dentry), stat); |
| 865 | stat->blocks = lower_stat.blocks; |
| 866 | out: |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 867 | sdcardfs_put_lower_path(dentry, &lower_path); |
Daniel Rosenberg | 5080d24 | 2016-05-18 16:57:10 -0700 | [diff] [blame] | 868 | return err; |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 869 | } |
| 870 | |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 871 | const struct inode_operations sdcardfs_symlink_iops = { |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 872 | .permission2 = sdcardfs_permission, |
| 873 | .setattr2 = sdcardfs_setattr, |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 874 | /* XXX Following operations are implemented, |
| 875 | * but FUSE(sdcard) or FAT does not support them |
| 876 | * These methods are *NOT* perfectly tested. |
| 877 | .readlink = sdcardfs_readlink, |
| 878 | .follow_link = sdcardfs_follow_link, |
Daniel Campello | d1d080c | 2015-07-20 16:27:37 -0700 | [diff] [blame] | 879 | .put_link = kfree_put_link, |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 880 | */ |
| 881 | }; |
| 882 | |
| 883 | const struct inode_operations sdcardfs_dir_iops = { |
| 884 | .create = sdcardfs_create, |
| 885 | .lookup = sdcardfs_lookup, |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 886 | .permission = sdcardfs_permission_wrn, |
| 887 | .permission2 = sdcardfs_permission, |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 888 | .unlink = sdcardfs_unlink, |
| 889 | .mkdir = sdcardfs_mkdir, |
| 890 | .rmdir = sdcardfs_rmdir, |
| 891 | .rename = sdcardfs_rename, |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 892 | .setattr = sdcardfs_setattr_wrn, |
| 893 | .setattr2 = sdcardfs_setattr, |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 894 | .getattr = sdcardfs_getattr, |
| 895 | /* XXX Following operations are implemented, |
| 896 | * but FUSE(sdcard) or FAT does not support them |
| 897 | * These methods are *NOT* perfectly tested. |
| 898 | .symlink = sdcardfs_symlink, |
| 899 | .link = sdcardfs_link, |
| 900 | .mknod = sdcardfs_mknod, |
| 901 | */ |
| 902 | }; |
| 903 | |
| 904 | const struct inode_operations sdcardfs_main_iops = { |
Daniel Rosenberg | 9021927 | 2016-10-26 20:27:20 -0700 | [diff] [blame] | 905 | .permission = sdcardfs_permission_wrn, |
| 906 | .permission2 = sdcardfs_permission, |
| 907 | .setattr = sdcardfs_setattr_wrn, |
| 908 | .setattr2 = sdcardfs_setattr, |
Daniel Campello | 35c9e24 | 2015-07-20 16:23:50 -0700 | [diff] [blame] | 909 | .getattr = sdcardfs_getattr, |
| 910 | }; |