1e9be9d5eSMiklos Szeredi /* 2e9be9d5eSMiklos Szeredi * 3e9be9d5eSMiklos Szeredi * Copyright (C) 2011 Novell Inc. 4e9be9d5eSMiklos Szeredi * 5e9be9d5eSMiklos Szeredi * This program is free software; you can redistribute it and/or modify it 6e9be9d5eSMiklos Szeredi * under the terms of the GNU General Public License version 2 as published by 7e9be9d5eSMiklos Szeredi * the Free Software Foundation. 8e9be9d5eSMiklos Szeredi */ 9e9be9d5eSMiklos Szeredi 10fb5bb2c3SDavid Howells #include <linux/module.h> 11e9be9d5eSMiklos Szeredi #include <linux/fs.h> 12e9be9d5eSMiklos Szeredi #include <linux/slab.h> 13e9be9d5eSMiklos Szeredi #include <linux/file.h> 14e9be9d5eSMiklos Szeredi #include <linux/splice.h> 15e9be9d5eSMiklos Szeredi #include <linux/xattr.h> 16e9be9d5eSMiklos Szeredi #include <linux/security.h> 17e9be9d5eSMiklos Szeredi #include <linux/uaccess.h> 18174cd4b1SIngo Molnar #include <linux/sched/signal.h> 195b825c3aSIngo Molnar #include <linux/cred.h> 20e9be9d5eSMiklos Szeredi #include <linux/namei.h> 21fb5bb2c3SDavid Howells #include <linux/fdtable.h> 22fb5bb2c3SDavid Howells #include <linux/ratelimit.h> 233a1e819bSAmir Goldstein #include <linux/exportfs.h> 24e9be9d5eSMiklos Szeredi #include "overlayfs.h" 25e9be9d5eSMiklos Szeredi 26e9be9d5eSMiklos Szeredi #define OVL_COPY_UP_CHUNK_SIZE (1 << 20) 27e9be9d5eSMiklos Szeredi 28670c2324SMiklos Szeredi static int ovl_ccup_set(const char *buf, const struct kernel_param *param) 29fb5bb2c3SDavid Howells { 30670c2324SMiklos Szeredi pr_warn("overlayfs: \"check_copy_up\" module option is obsolete\n"); 31fb5bb2c3SDavid Howells return 0; 32fb5bb2c3SDavid Howells } 33fb5bb2c3SDavid Howells 34670c2324SMiklos Szeredi static int ovl_ccup_get(char *buf, const struct kernel_param *param) 35fb5bb2c3SDavid Howells { 36670c2324SMiklos Szeredi return sprintf(buf, "N\n"); 37fb5bb2c3SDavid Howells } 38fb5bb2c3SDavid Howells 39670c2324SMiklos Szeredi module_param_call(check_copy_up, ovl_ccup_set, ovl_ccup_get, NULL, 0644); 40670c2324SMiklos Szeredi MODULE_PARM_DESC(ovl_check_copy_up, "Obsolete; does nothing"); 41670c2324SMiklos Szeredi 42e9be9d5eSMiklos Szeredi int ovl_copy_xattr(struct dentry *old, struct dentry *new) 43e9be9d5eSMiklos Szeredi { 44e4ad29faSVito Caputo ssize_t list_size, size, value_size = 0; 45e4ad29faSVito Caputo char *buf, *name, *value = NULL; 46e4ad29faSVito Caputo int uninitialized_var(error); 478b326c61SMiklos Szeredi size_t slen; 48e9be9d5eSMiklos Szeredi 495d6c3191SAndreas Gruenbacher if (!(old->d_inode->i_opflags & IOP_XATTR) || 505d6c3191SAndreas Gruenbacher !(new->d_inode->i_opflags & IOP_XATTR)) 51e9be9d5eSMiklos Szeredi return 0; 52e9be9d5eSMiklos Szeredi 53e9be9d5eSMiklos Szeredi list_size = vfs_listxattr(old, NULL, 0); 54e9be9d5eSMiklos Szeredi if (list_size <= 0) { 55e9be9d5eSMiklos Szeredi if (list_size == -EOPNOTSUPP) 56e9be9d5eSMiklos Szeredi return 0; 57e9be9d5eSMiklos Szeredi return list_size; 58e9be9d5eSMiklos Szeredi } 59e9be9d5eSMiklos Szeredi 60e9be9d5eSMiklos Szeredi buf = kzalloc(list_size, GFP_KERNEL); 61e9be9d5eSMiklos Szeredi if (!buf) 62e9be9d5eSMiklos Szeredi return -ENOMEM; 63e9be9d5eSMiklos Szeredi 64e9be9d5eSMiklos Szeredi list_size = vfs_listxattr(old, buf, list_size); 65e9be9d5eSMiklos Szeredi if (list_size <= 0) { 66e9be9d5eSMiklos Szeredi error = list_size; 67e4ad29faSVito Caputo goto out; 68e9be9d5eSMiklos Szeredi } 69e9be9d5eSMiklos Szeredi 708b326c61SMiklos Szeredi for (name = buf; list_size; name += slen) { 718b326c61SMiklos Szeredi slen = strnlen(name, list_size) + 1; 728b326c61SMiklos Szeredi 738b326c61SMiklos Szeredi /* underlying fs providing us with an broken xattr list? */ 748b326c61SMiklos Szeredi if (WARN_ON(slen > list_size)) { 758b326c61SMiklos Szeredi error = -EIO; 768b326c61SMiklos Szeredi break; 778b326c61SMiklos Szeredi } 788b326c61SMiklos Szeredi list_size -= slen; 798b326c61SMiklos Szeredi 800956254aSMiklos Szeredi if (ovl_is_private_xattr(name)) 810956254aSMiklos Szeredi continue; 82e4ad29faSVito Caputo retry: 83e4ad29faSVito Caputo size = vfs_getxattr(old, name, value, value_size); 84e4ad29faSVito Caputo if (size == -ERANGE) 85e4ad29faSVito Caputo size = vfs_getxattr(old, name, NULL, 0); 86e4ad29faSVito Caputo 8797daf8b9SMiklos Szeredi if (size < 0) { 88e9be9d5eSMiklos Szeredi error = size; 89e4ad29faSVito Caputo break; 90e9be9d5eSMiklos Szeredi } 91e9be9d5eSMiklos Szeredi 92e4ad29faSVito Caputo if (size > value_size) { 93e4ad29faSVito Caputo void *new; 94e4ad29faSVito Caputo 95e4ad29faSVito Caputo new = krealloc(value, size, GFP_KERNEL); 96e4ad29faSVito Caputo if (!new) { 97e4ad29faSVito Caputo error = -ENOMEM; 98e4ad29faSVito Caputo break; 99e4ad29faSVito Caputo } 100e4ad29faSVito Caputo value = new; 101e4ad29faSVito Caputo value_size = size; 102e4ad29faSVito Caputo goto retry; 103e4ad29faSVito Caputo } 104e4ad29faSVito Caputo 105121ab822SVivek Goyal error = security_inode_copy_up_xattr(name); 106121ab822SVivek Goyal if (error < 0 && error != -EOPNOTSUPP) 107121ab822SVivek Goyal break; 108121ab822SVivek Goyal if (error == 1) { 109121ab822SVivek Goyal error = 0; 110121ab822SVivek Goyal continue; /* Discard */ 111121ab822SVivek Goyal } 112e4ad29faSVito Caputo error = vfs_setxattr(new, name, value, size, 0); 113e4ad29faSVito Caputo if (error) 114e4ad29faSVito Caputo break; 115e4ad29faSVito Caputo } 116e9be9d5eSMiklos Szeredi kfree(value); 117e9be9d5eSMiklos Szeredi out: 118e9be9d5eSMiklos Szeredi kfree(buf); 119e9be9d5eSMiklos Szeredi return error; 120e9be9d5eSMiklos Szeredi } 121e9be9d5eSMiklos Szeredi 122e9be9d5eSMiklos Szeredi static int ovl_copy_up_data(struct path *old, struct path *new, loff_t len) 123e9be9d5eSMiklos Szeredi { 124e9be9d5eSMiklos Szeredi struct file *old_file; 125e9be9d5eSMiklos Szeredi struct file *new_file; 126e9be9d5eSMiklos Szeredi loff_t old_pos = 0; 127e9be9d5eSMiklos Szeredi loff_t new_pos = 0; 12842ec3d4cSDarrick J. Wong loff_t cloned; 129e9be9d5eSMiklos Szeredi int error = 0; 130e9be9d5eSMiklos Szeredi 131e9be9d5eSMiklos Szeredi if (len == 0) 132e9be9d5eSMiklos Szeredi return 0; 133e9be9d5eSMiklos Szeredi 1340480334fSDavid Howells old_file = ovl_path_open(old, O_LARGEFILE | O_RDONLY); 135e9be9d5eSMiklos Szeredi if (IS_ERR(old_file)) 136e9be9d5eSMiklos Szeredi return PTR_ERR(old_file); 137e9be9d5eSMiklos Szeredi 1380480334fSDavid Howells new_file = ovl_path_open(new, O_LARGEFILE | O_WRONLY); 139e9be9d5eSMiklos Szeredi if (IS_ERR(new_file)) { 140e9be9d5eSMiklos Szeredi error = PTR_ERR(new_file); 141e9be9d5eSMiklos Szeredi goto out_fput; 142e9be9d5eSMiklos Szeredi } 143e9be9d5eSMiklos Szeredi 1442ea98466SAmir Goldstein /* Try to use clone_file_range to clone up within the same fs */ 145452ce659SDarrick J. Wong cloned = do_clone_file_range(old_file, 0, new_file, 0, len, 0); 14642ec3d4cSDarrick J. Wong if (cloned == len) 1472ea98466SAmir Goldstein goto out; 1482ea98466SAmir Goldstein /* Couldn't clone, so now we try to copy the data */ 1492ea98466SAmir Goldstein 150e9be9d5eSMiklos Szeredi /* FIXME: copy up sparse files efficiently */ 151e9be9d5eSMiklos Szeredi while (len) { 152e9be9d5eSMiklos Szeredi size_t this_len = OVL_COPY_UP_CHUNK_SIZE; 153e9be9d5eSMiklos Szeredi long bytes; 154e9be9d5eSMiklos Szeredi 155e9be9d5eSMiklos Szeredi if (len < this_len) 156e9be9d5eSMiklos Szeredi this_len = len; 157e9be9d5eSMiklos Szeredi 158e9be9d5eSMiklos Szeredi if (signal_pending_state(TASK_KILLABLE, current)) { 159e9be9d5eSMiklos Szeredi error = -EINTR; 160e9be9d5eSMiklos Szeredi break; 161e9be9d5eSMiklos Szeredi } 162e9be9d5eSMiklos Szeredi 163e9be9d5eSMiklos Szeredi bytes = do_splice_direct(old_file, &old_pos, 164e9be9d5eSMiklos Szeredi new_file, &new_pos, 165e9be9d5eSMiklos Szeredi this_len, SPLICE_F_MOVE); 166e9be9d5eSMiklos Szeredi if (bytes <= 0) { 167e9be9d5eSMiklos Szeredi error = bytes; 168e9be9d5eSMiklos Szeredi break; 169e9be9d5eSMiklos Szeredi } 170e9be9d5eSMiklos Szeredi WARN_ON(old_pos != new_pos); 171e9be9d5eSMiklos Szeredi 172e9be9d5eSMiklos Szeredi len -= bytes; 173e9be9d5eSMiklos Szeredi } 1742ea98466SAmir Goldstein out: 175641089c1SMiklos Szeredi if (!error) 176641089c1SMiklos Szeredi error = vfs_fsync(new_file, 0); 177e9be9d5eSMiklos Szeredi fput(new_file); 178e9be9d5eSMiklos Szeredi out_fput: 179e9be9d5eSMiklos Szeredi fput(old_file); 180e9be9d5eSMiklos Szeredi return error; 181e9be9d5eSMiklos Szeredi } 182e9be9d5eSMiklos Szeredi 1830c288874SVivek Goyal static int ovl_set_size(struct dentry *upperdentry, struct kstat *stat) 1840c288874SVivek Goyal { 1850c288874SVivek Goyal struct iattr attr = { 1860c288874SVivek Goyal .ia_valid = ATTR_SIZE, 1870c288874SVivek Goyal .ia_size = stat->size, 1880c288874SVivek Goyal }; 1890c288874SVivek Goyal 1900c288874SVivek Goyal return notify_change(upperdentry, &attr, NULL); 1910c288874SVivek Goyal } 1920c288874SVivek Goyal 193e9be9d5eSMiklos Szeredi static int ovl_set_timestamps(struct dentry *upperdentry, struct kstat *stat) 194e9be9d5eSMiklos Szeredi { 195e9be9d5eSMiklos Szeredi struct iattr attr = { 196e9be9d5eSMiklos Szeredi .ia_valid = 197e9be9d5eSMiklos Szeredi ATTR_ATIME | ATTR_MTIME | ATTR_ATIME_SET | ATTR_MTIME_SET, 198e9be9d5eSMiklos Szeredi .ia_atime = stat->atime, 199e9be9d5eSMiklos Szeredi .ia_mtime = stat->mtime, 200e9be9d5eSMiklos Szeredi }; 201e9be9d5eSMiklos Szeredi 202e9be9d5eSMiklos Szeredi return notify_change(upperdentry, &attr, NULL); 203e9be9d5eSMiklos Szeredi } 204e9be9d5eSMiklos Szeredi 205e9be9d5eSMiklos Szeredi int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat) 206e9be9d5eSMiklos Szeredi { 207e9be9d5eSMiklos Szeredi int err = 0; 208e9be9d5eSMiklos Szeredi 209e9be9d5eSMiklos Szeredi if (!S_ISLNK(stat->mode)) { 210e9be9d5eSMiklos Szeredi struct iattr attr = { 211e9be9d5eSMiklos Szeredi .ia_valid = ATTR_MODE, 212e9be9d5eSMiklos Szeredi .ia_mode = stat->mode, 213e9be9d5eSMiklos Szeredi }; 214e9be9d5eSMiklos Szeredi err = notify_change(upperdentry, &attr, NULL); 215e9be9d5eSMiklos Szeredi } 216e9be9d5eSMiklos Szeredi if (!err) { 217e9be9d5eSMiklos Szeredi struct iattr attr = { 218e9be9d5eSMiklos Szeredi .ia_valid = ATTR_UID | ATTR_GID, 219e9be9d5eSMiklos Szeredi .ia_uid = stat->uid, 220e9be9d5eSMiklos Szeredi .ia_gid = stat->gid, 221e9be9d5eSMiklos Szeredi }; 222e9be9d5eSMiklos Szeredi err = notify_change(upperdentry, &attr, NULL); 223e9be9d5eSMiklos Szeredi } 224e9be9d5eSMiklos Szeredi if (!err) 225e9be9d5eSMiklos Szeredi ovl_set_timestamps(upperdentry, stat); 226e9be9d5eSMiklos Szeredi 227e9be9d5eSMiklos Szeredi return err; 228e9be9d5eSMiklos Szeredi } 229e9be9d5eSMiklos Szeredi 2305b2cccd3SAmir Goldstein struct ovl_fh *ovl_encode_real_fh(struct dentry *real, bool is_upper) 2313a1e819bSAmir Goldstein { 2323a1e819bSAmir Goldstein struct ovl_fh *fh; 2333a1e819bSAmir Goldstein int fh_type, fh_len, dwords; 2343a1e819bSAmir Goldstein void *buf; 2353a1e819bSAmir Goldstein int buflen = MAX_HANDLE_SZ; 23605122443SAmir Goldstein uuid_t *uuid = &real->d_sb->s_uuid; 2373a1e819bSAmir Goldstein 2380ee931c4SMichal Hocko buf = kmalloc(buflen, GFP_KERNEL); 2393a1e819bSAmir Goldstein if (!buf) 2403a1e819bSAmir Goldstein return ERR_PTR(-ENOMEM); 2413a1e819bSAmir Goldstein 2423a1e819bSAmir Goldstein /* 2433a1e819bSAmir Goldstein * We encode a non-connectable file handle for non-dir, because we 2443a1e819bSAmir Goldstein * only need to find the lower inode number and we don't want to pay 2453a1e819bSAmir Goldstein * the price or reconnecting the dentry. 2463a1e819bSAmir Goldstein */ 2473a1e819bSAmir Goldstein dwords = buflen >> 2; 24805122443SAmir Goldstein fh_type = exportfs_encode_fh(real, buf, &dwords, 0); 2493a1e819bSAmir Goldstein buflen = (dwords << 2); 2503a1e819bSAmir Goldstein 2513a1e819bSAmir Goldstein fh = ERR_PTR(-EIO); 2523a1e819bSAmir Goldstein if (WARN_ON(fh_type < 0) || 2533a1e819bSAmir Goldstein WARN_ON(buflen > MAX_HANDLE_SZ) || 2543a1e819bSAmir Goldstein WARN_ON(fh_type == FILEID_INVALID)) 2553a1e819bSAmir Goldstein goto out; 2563a1e819bSAmir Goldstein 2573a1e819bSAmir Goldstein BUILD_BUG_ON(MAX_HANDLE_SZ + offsetof(struct ovl_fh, fid) > 255); 2583a1e819bSAmir Goldstein fh_len = offsetof(struct ovl_fh, fid) + buflen; 2593a1e819bSAmir Goldstein fh = kmalloc(fh_len, GFP_KERNEL); 2603a1e819bSAmir Goldstein if (!fh) { 2613a1e819bSAmir Goldstein fh = ERR_PTR(-ENOMEM); 2623a1e819bSAmir Goldstein goto out; 2633a1e819bSAmir Goldstein } 2643a1e819bSAmir Goldstein 2653a1e819bSAmir Goldstein fh->version = OVL_FH_VERSION; 2663a1e819bSAmir Goldstein fh->magic = OVL_FH_MAGIC; 2673a1e819bSAmir Goldstein fh->type = fh_type; 2683a1e819bSAmir Goldstein fh->flags = OVL_FH_FLAG_CPU_ENDIAN; 26954fb347eSAmir Goldstein /* 27054fb347eSAmir Goldstein * When we will want to decode an overlay dentry from this handle 27154fb347eSAmir Goldstein * and all layers are on the same fs, if we get a disconncted real 27254fb347eSAmir Goldstein * dentry when we decode fid, the only way to tell if we should assign 27354fb347eSAmir Goldstein * it to upperdentry or to lowerstack is by checking this flag. 27454fb347eSAmir Goldstein */ 27554fb347eSAmir Goldstein if (is_upper) 27654fb347eSAmir Goldstein fh->flags |= OVL_FH_FLAG_PATH_UPPER; 2773a1e819bSAmir Goldstein fh->len = fh_len; 2783a1e819bSAmir Goldstein fh->uuid = *uuid; 2793a1e819bSAmir Goldstein memcpy(fh->fid, buf, buflen); 2803a1e819bSAmir Goldstein 2813a1e819bSAmir Goldstein out: 2823a1e819bSAmir Goldstein kfree(buf); 2833a1e819bSAmir Goldstein return fh; 2843a1e819bSAmir Goldstein } 2853a1e819bSAmir Goldstein 2869678e630SAmir Goldstein int ovl_set_origin(struct dentry *dentry, struct dentry *lower, 2873a1e819bSAmir Goldstein struct dentry *upper) 2883a1e819bSAmir Goldstein { 2893a1e819bSAmir Goldstein const struct ovl_fh *fh = NULL; 2903a1e819bSAmir Goldstein int err; 2913a1e819bSAmir Goldstein 2923a1e819bSAmir Goldstein /* 2933a1e819bSAmir Goldstein * When lower layer doesn't support export operations store a 'null' fh, 2943a1e819bSAmir Goldstein * so we can use the overlay.origin xattr to distignuish between a copy 2953a1e819bSAmir Goldstein * up and a pure upper inode. 2963a1e819bSAmir Goldstein */ 29702bcd157SAmir Goldstein if (ovl_can_decode_fh(lower->d_sb)) { 2985b2cccd3SAmir Goldstein fh = ovl_encode_real_fh(lower, false); 2993a1e819bSAmir Goldstein if (IS_ERR(fh)) 3003a1e819bSAmir Goldstein return PTR_ERR(fh); 3013a1e819bSAmir Goldstein } 3023a1e819bSAmir Goldstein 3036266d465SMiklos Szeredi /* 3046266d465SMiklos Szeredi * Do not fail when upper doesn't support xattrs. 3056266d465SMiklos Szeredi */ 3066266d465SMiklos Szeredi err = ovl_check_setxattr(dentry, upper, OVL_XATTR_ORIGIN, fh, 3076266d465SMiklos Szeredi fh ? fh->len : 0, 0); 3083a1e819bSAmir Goldstein kfree(fh); 3093a1e819bSAmir Goldstein 3103a1e819bSAmir Goldstein return err; 3113a1e819bSAmir Goldstein } 3123a1e819bSAmir Goldstein 313016b720fSAmir Goldstein /* Store file handle of @upper dir in @index dir entry */ 314016b720fSAmir Goldstein static int ovl_set_upper_fh(struct dentry *upper, struct dentry *index) 315016b720fSAmir Goldstein { 316016b720fSAmir Goldstein const struct ovl_fh *fh; 317016b720fSAmir Goldstein int err; 318016b720fSAmir Goldstein 3195b2cccd3SAmir Goldstein fh = ovl_encode_real_fh(upper, true); 320016b720fSAmir Goldstein if (IS_ERR(fh)) 321016b720fSAmir Goldstein return PTR_ERR(fh); 322016b720fSAmir Goldstein 323016b720fSAmir Goldstein err = ovl_do_setxattr(index, OVL_XATTR_UPPER, fh, fh->len, 0); 324016b720fSAmir Goldstein 325016b720fSAmir Goldstein kfree(fh); 326016b720fSAmir Goldstein return err; 327016b720fSAmir Goldstein } 328016b720fSAmir Goldstein 329016b720fSAmir Goldstein /* 330016b720fSAmir Goldstein * Create and install index entry. 331016b720fSAmir Goldstein * 332016b720fSAmir Goldstein * Caller must hold i_mutex on indexdir. 333016b720fSAmir Goldstein */ 334016b720fSAmir Goldstein static int ovl_create_index(struct dentry *dentry, struct dentry *origin, 335016b720fSAmir Goldstein struct dentry *upper) 336016b720fSAmir Goldstein { 337016b720fSAmir Goldstein struct dentry *indexdir = ovl_indexdir(dentry->d_sb); 338016b720fSAmir Goldstein struct inode *dir = d_inode(indexdir); 339016b720fSAmir Goldstein struct dentry *index = NULL; 340016b720fSAmir Goldstein struct dentry *temp = NULL; 341016b720fSAmir Goldstein struct qstr name = { }; 342016b720fSAmir Goldstein int err; 343016b720fSAmir Goldstein 344016b720fSAmir Goldstein /* 345016b720fSAmir Goldstein * For now this is only used for creating index entry for directories, 346016b720fSAmir Goldstein * because non-dir are copied up directly to index and then hardlinked 347016b720fSAmir Goldstein * to upper dir. 348016b720fSAmir Goldstein * 349016b720fSAmir Goldstein * TODO: implement create index for non-dir, so we can call it when 350016b720fSAmir Goldstein * encoding file handle for non-dir in case index does not exist. 351016b720fSAmir Goldstein */ 352016b720fSAmir Goldstein if (WARN_ON(!d_is_dir(dentry))) 353016b720fSAmir Goldstein return -EIO; 354016b720fSAmir Goldstein 355016b720fSAmir Goldstein /* Directory not expected to be indexed before copy up */ 356016b720fSAmir Goldstein if (WARN_ON(ovl_test_flag(OVL_INDEX, d_inode(dentry)))) 357016b720fSAmir Goldstein return -EIO; 358016b720fSAmir Goldstein 359016b720fSAmir Goldstein err = ovl_get_index_name(origin, &name); 360016b720fSAmir Goldstein if (err) 361016b720fSAmir Goldstein return err; 362016b720fSAmir Goldstein 363137ec526SAmir Goldstein temp = ovl_create_temp(indexdir, OVL_CATTR(S_IFDIR | 0)); 364b148cba4SMiklos Szeredi err = PTR_ERR(temp); 365016b720fSAmir Goldstein if (IS_ERR(temp)) 366b148cba4SMiklos Szeredi goto free_name; 367016b720fSAmir Goldstein 368016b720fSAmir Goldstein err = ovl_set_upper_fh(upper, temp); 369016b720fSAmir Goldstein if (err) 370b148cba4SMiklos Szeredi goto out; 371016b720fSAmir Goldstein 372016b720fSAmir Goldstein index = lookup_one_len(name.name, indexdir, name.len); 373016b720fSAmir Goldstein if (IS_ERR(index)) { 374016b720fSAmir Goldstein err = PTR_ERR(index); 375016b720fSAmir Goldstein } else { 376016b720fSAmir Goldstein err = ovl_do_rename(dir, temp, dir, index, 0); 377016b720fSAmir Goldstein dput(index); 378016b720fSAmir Goldstein } 379016b720fSAmir Goldstein out: 380b148cba4SMiklos Szeredi if (err) 381b148cba4SMiklos Szeredi ovl_cleanup(dir, temp); 382016b720fSAmir Goldstein dput(temp); 383b148cba4SMiklos Szeredi free_name: 384016b720fSAmir Goldstein kfree(name.name); 385016b720fSAmir Goldstein return err; 386016b720fSAmir Goldstein } 387016b720fSAmir Goldstein 38823f0ab13SMiklos Szeredi struct ovl_copy_up_ctx { 389a6fb235aSMiklos Szeredi struct dentry *parent; 39023f0ab13SMiklos Szeredi struct dentry *dentry; 39123f0ab13SMiklos Szeredi struct path lowerpath; 39223f0ab13SMiklos Szeredi struct kstat stat; 39323f0ab13SMiklos Szeredi struct kstat pstat; 39423f0ab13SMiklos Szeredi const char *link; 39559be0971SAmir Goldstein struct dentry *destdir; 39659be0971SAmir Goldstein struct qstr destname; 39723f0ab13SMiklos Szeredi struct dentry *workdir; 39859be0971SAmir Goldstein bool origin; 399016b720fSAmir Goldstein bool indexed; 40044d5bf10SVivek Goyal bool metacopy; 40123f0ab13SMiklos Szeredi }; 40223f0ab13SMiklos Szeredi 403f4439de1SAmir Goldstein static int ovl_link_up(struct ovl_copy_up_ctx *c) 404f4439de1SAmir Goldstein { 405f4439de1SAmir Goldstein int err; 406f4439de1SAmir Goldstein struct dentry *upper; 407f4439de1SAmir Goldstein struct dentry *upperdir = ovl_dentry_upper(c->parent); 408f4439de1SAmir Goldstein struct inode *udir = d_inode(upperdir); 409f4439de1SAmir Goldstein 410f4439de1SAmir Goldstein /* Mark parent "impure" because it may now contain non-pure upper */ 411f4439de1SAmir Goldstein err = ovl_set_impure(c->parent, upperdir); 412f4439de1SAmir Goldstein if (err) 413f4439de1SAmir Goldstein return err; 414f4439de1SAmir Goldstein 415f4439de1SAmir Goldstein err = ovl_set_nlink_lower(c->dentry); 416f4439de1SAmir Goldstein if (err) 417f4439de1SAmir Goldstein return err; 418f4439de1SAmir Goldstein 419f4439de1SAmir Goldstein inode_lock_nested(udir, I_MUTEX_PARENT); 420f4439de1SAmir Goldstein upper = lookup_one_len(c->dentry->d_name.name, upperdir, 421f4439de1SAmir Goldstein c->dentry->d_name.len); 422f4439de1SAmir Goldstein err = PTR_ERR(upper); 423f4439de1SAmir Goldstein if (!IS_ERR(upper)) { 4246cf00764SAmir Goldstein err = ovl_do_link(ovl_dentry_upper(c->dentry), udir, upper); 425f4439de1SAmir Goldstein dput(upper); 426f4439de1SAmir Goldstein 427f4439de1SAmir Goldstein if (!err) { 428f4439de1SAmir Goldstein /* Restore timestamps on parent (best effort) */ 429f4439de1SAmir Goldstein ovl_set_timestamps(upperdir, &c->pstat); 430f4439de1SAmir Goldstein ovl_dentry_set_upper_alias(c->dentry); 431f4439de1SAmir Goldstein } 432f4439de1SAmir Goldstein } 433f4439de1SAmir Goldstein inode_unlock(udir); 434aa3ff3c1SAmir Goldstein if (err) 435aa3ff3c1SAmir Goldstein return err; 436aa3ff3c1SAmir Goldstein 437aa3ff3c1SAmir Goldstein err = ovl_set_nlink_upper(c->dentry); 438f4439de1SAmir Goldstein 439f4439de1SAmir Goldstein return err; 440f4439de1SAmir Goldstein } 441f4439de1SAmir Goldstein 44223f0ab13SMiklos Szeredi static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp) 44302209d10SAmir Goldstein { 44402209d10SAmir Goldstein int err; 44502209d10SAmir Goldstein 4465f32879eSVivek Goyal /* 4475f32879eSVivek Goyal * Copy up data first and then xattrs. Writing data after 4485f32879eSVivek Goyal * xattrs will remove security.capability xattr automatically. 4495f32879eSVivek Goyal */ 4505f32879eSVivek Goyal if (S_ISREG(c->stat.mode) && !c->metacopy) { 4515f32879eSVivek Goyal struct path upperpath, datapath; 4525f32879eSVivek Goyal 4535f32879eSVivek Goyal ovl_path_upper(c->dentry, &upperpath); 4545f32879eSVivek Goyal if (WARN_ON(upperpath.dentry != NULL)) 4555f32879eSVivek Goyal return -EIO; 4565f32879eSVivek Goyal upperpath.dentry = temp; 4575f32879eSVivek Goyal 4585f32879eSVivek Goyal ovl_path_lowerdata(c->dentry, &datapath); 4595f32879eSVivek Goyal err = ovl_copy_up_data(&datapath, &upperpath, c->stat.size); 4605f32879eSVivek Goyal if (err) 4615f32879eSVivek Goyal return err; 4625f32879eSVivek Goyal } 4635f32879eSVivek Goyal 46423f0ab13SMiklos Szeredi err = ovl_copy_xattr(c->lowerpath.dentry, temp); 46502209d10SAmir Goldstein if (err) 46602209d10SAmir Goldstein return err; 46702209d10SAmir Goldstein 46802209d10SAmir Goldstein /* 46902209d10SAmir Goldstein * Store identifier of lower inode in upper inode xattr to 47002209d10SAmir Goldstein * allow lookup of the copy up origin inode. 47102209d10SAmir Goldstein * 47202209d10SAmir Goldstein * Don't set origin when we are breaking the association with a lower 47302209d10SAmir Goldstein * hard link. 47402209d10SAmir Goldstein */ 47559be0971SAmir Goldstein if (c->origin) { 47623f0ab13SMiklos Szeredi err = ovl_set_origin(c->dentry, c->lowerpath.dentry, temp); 47702209d10SAmir Goldstein if (err) 47802209d10SAmir Goldstein return err; 47902209d10SAmir Goldstein } 48002209d10SAmir Goldstein 4810c288874SVivek Goyal if (c->metacopy) { 4820c288874SVivek Goyal err = ovl_check_setxattr(c->dentry, temp, OVL_XATTR_METACOPY, 4830c288874SVivek Goyal NULL, 0, -EOPNOTSUPP); 4840c288874SVivek Goyal if (err) 4850c288874SVivek Goyal return err; 4860c288874SVivek Goyal } 4870c288874SVivek Goyal 488bd64e575SVivek Goyal inode_lock(temp->d_inode); 4890c288874SVivek Goyal if (c->metacopy) 4900c288874SVivek Goyal err = ovl_set_size(temp, &c->stat); 4910c288874SVivek Goyal if (!err) 492bd64e575SVivek Goyal err = ovl_set_attr(temp, &c->stat); 493bd64e575SVivek Goyal inode_unlock(temp->d_inode); 494bd64e575SVivek Goyal 495bd64e575SVivek Goyal return err; 49602209d10SAmir Goldstein } 49702209d10SAmir Goldstein 4986b52243fSMiklos Szeredi struct ovl_cu_creds { 4996b52243fSMiklos Szeredi const struct cred *old; 5006b52243fSMiklos Szeredi struct cred *new; 501b10cdcdcSAmir Goldstein }; 502b10cdcdcSAmir Goldstein 5036b52243fSMiklos Szeredi static int ovl_prep_cu_creds(struct dentry *dentry, struct ovl_cu_creds *cc) 504b10cdcdcSAmir Goldstein { 505b10cdcdcSAmir Goldstein int err; 506b10cdcdcSAmir Goldstein 5076b52243fSMiklos Szeredi cc->old = cc->new = NULL; 5086b52243fSMiklos Szeredi err = security_inode_copy_up(dentry, &cc->new); 5096b52243fSMiklos Szeredi if (err < 0) 510b10cdcdcSAmir Goldstein return err; 5116b52243fSMiklos Szeredi 5126b52243fSMiklos Szeredi if (cc->new) 5136b52243fSMiklos Szeredi cc->old = override_creds(cc->new); 5146b52243fSMiklos Szeredi 5156b52243fSMiklos Szeredi return 0; 5166b52243fSMiklos Szeredi } 5176b52243fSMiklos Szeredi 5186b52243fSMiklos Szeredi static void ovl_revert_cu_creds(struct ovl_cu_creds *cc) 5196b52243fSMiklos Szeredi { 5206b52243fSMiklos Szeredi if (cc->new) { 5216b52243fSMiklos Szeredi revert_creds(cc->old); 5226b52243fSMiklos Szeredi put_cred(cc->new); 5236b52243fSMiklos Szeredi } 524b10cdcdcSAmir Goldstein } 525b10cdcdcSAmir Goldstein 526b10cdcdcSAmir Goldstein /* 527b10cdcdcSAmir Goldstein * Copyup using workdir to prepare temp file. Used when copying up directories, 528b10cdcdcSAmir Goldstein * special files or when upper fs doesn't support O_TMPFILE. 529b10cdcdcSAmir Goldstein */ 530b10cdcdcSAmir Goldstein static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c) 531b10cdcdcSAmir Goldstein { 532b79e05aaSAmir Goldstein struct inode *inode; 5336b52243fSMiklos Szeredi struct inode *udir = d_inode(c->destdir), *wdir = d_inode(c->workdir); 5346b52243fSMiklos Szeredi struct dentry *temp, *upper; 5356b52243fSMiklos Szeredi struct ovl_cu_creds cc; 5367d90b853SMiklos Szeredi int err; 5376b52243fSMiklos Szeredi struct ovl_cattr cattr = { 5386b52243fSMiklos Szeredi /* Can't properly set mode on creation because of the umask */ 5396b52243fSMiklos Szeredi .mode = c->stat.mode & S_IFMT, 5406b52243fSMiklos Szeredi .rdev = c->stat.rdev, 5416b52243fSMiklos Szeredi .link = c->link 5426b52243fSMiklos Szeredi }; 5437d90b853SMiklos Szeredi 544b10cdcdcSAmir Goldstein err = ovl_lock_rename_workdir(c->workdir, c->destdir); 545b10cdcdcSAmir Goldstein if (err) 546b10cdcdcSAmir Goldstein return err; 547b10cdcdcSAmir Goldstein 5486b52243fSMiklos Szeredi err = ovl_prep_cu_creds(c->dentry, &cc); 5496b52243fSMiklos Szeredi if (err) 5506b52243fSMiklos Szeredi goto unlock; 5516b52243fSMiklos Szeredi 5526b52243fSMiklos Szeredi temp = ovl_create_temp(c->workdir, &cattr); 5536b52243fSMiklos Szeredi ovl_revert_cu_creds(&cc); 5546b52243fSMiklos Szeredi 555b10cdcdcSAmir Goldstein err = PTR_ERR(temp); 556b10cdcdcSAmir Goldstein if (IS_ERR(temp)) 557b10cdcdcSAmir Goldstein goto unlock; 558b10cdcdcSAmir Goldstein 559b10cdcdcSAmir Goldstein err = ovl_copy_up_inode(c, temp); 560b10cdcdcSAmir Goldstein if (err) 561b10cdcdcSAmir Goldstein goto cleanup; 562b10cdcdcSAmir Goldstein 563b10cdcdcSAmir Goldstein if (S_ISDIR(c->stat.mode) && c->indexed) { 564b10cdcdcSAmir Goldstein err = ovl_create_index(c->dentry, c->lowerpath.dentry, temp); 565b10cdcdcSAmir Goldstein if (err) 566b10cdcdcSAmir Goldstein goto cleanup; 567b10cdcdcSAmir Goldstein } 568b10cdcdcSAmir Goldstein 5696b52243fSMiklos Szeredi upper = lookup_one_len(c->destname.name, c->destdir, c->destname.len); 5706b52243fSMiklos Szeredi err = PTR_ERR(upper); 5716b52243fSMiklos Szeredi if (IS_ERR(upper)) 5726b52243fSMiklos Szeredi goto cleanup; 5736b52243fSMiklos Szeredi 5746b52243fSMiklos Szeredi err = ovl_do_rename(wdir, temp, udir, upper, 0); 5756b52243fSMiklos Szeredi dput(upper); 576b10cdcdcSAmir Goldstein if (err) 577b10cdcdcSAmir Goldstein goto cleanup; 578b10cdcdcSAmir Goldstein 579b10cdcdcSAmir Goldstein if (!c->metacopy) 580b10cdcdcSAmir Goldstein ovl_set_upperdata(d_inode(c->dentry)); 581b10cdcdcSAmir Goldstein inode = d_inode(c->dentry); 5826b52243fSMiklos Szeredi ovl_inode_update(inode, temp); 583b10cdcdcSAmir Goldstein if (S_ISDIR(inode->i_mode)) 584b10cdcdcSAmir Goldstein ovl_set_flag(OVL_WHITEOUTS, inode); 585b10cdcdcSAmir Goldstein unlock: 586b10cdcdcSAmir Goldstein unlock_rename(c->workdir, c->destdir); 587b10cdcdcSAmir Goldstein 588b10cdcdcSAmir Goldstein return err; 589b10cdcdcSAmir Goldstein 590b10cdcdcSAmir Goldstein cleanup: 5916b52243fSMiklos Szeredi ovl_cleanup(wdir, temp); 5926b52243fSMiklos Szeredi dput(temp); 593b10cdcdcSAmir Goldstein goto unlock; 594b10cdcdcSAmir Goldstein } 595b10cdcdcSAmir Goldstein 596b10cdcdcSAmir Goldstein /* Copyup using O_TMPFILE which does not require cross dir locking */ 597b10cdcdcSAmir Goldstein static int ovl_copy_up_tmpfile(struct ovl_copy_up_ctx *c) 598b10cdcdcSAmir Goldstein { 5996b52243fSMiklos Szeredi struct inode *udir = d_inode(c->destdir); 6006b52243fSMiklos Szeredi struct dentry *temp, *upper; 6016b52243fSMiklos Szeredi struct ovl_cu_creds cc; 602b10cdcdcSAmir Goldstein int err; 603b10cdcdcSAmir Goldstein 6046b52243fSMiklos Szeredi err = ovl_prep_cu_creds(c->dentry, &cc); 6056b52243fSMiklos Szeredi if (err) 6066b52243fSMiklos Szeredi return err; 6076b52243fSMiklos Szeredi 6086b52243fSMiklos Szeredi temp = ovl_do_tmpfile(c->workdir, c->stat.mode); 6096b52243fSMiklos Szeredi ovl_revert_cu_creds(&cc); 6106b52243fSMiklos Szeredi 611b148cba4SMiklos Szeredi if (IS_ERR(temp)) 612b148cba4SMiklos Szeredi return PTR_ERR(temp); 613e9be9d5eSMiklos Szeredi 61423f0ab13SMiklos Szeredi err = ovl_copy_up_inode(c, temp); 615e9be9d5eSMiklos Szeredi if (err) 6166b52243fSMiklos Szeredi goto out_dput; 6173a1e819bSAmir Goldstein 6186b52243fSMiklos Szeredi inode_lock_nested(udir, I_MUTEX_PARENT); 6196b52243fSMiklos Szeredi 6206b52243fSMiklos Szeredi upper = lookup_one_len(c->destname.name, c->destdir, c->destname.len); 6216b52243fSMiklos Szeredi err = PTR_ERR(upper); 6226b52243fSMiklos Szeredi if (!IS_ERR(upper)) { 6236b52243fSMiklos Szeredi err = ovl_do_link(temp, udir, upper); 6246b52243fSMiklos Szeredi dput(upper); 6256b52243fSMiklos Szeredi } 6266b52243fSMiklos Szeredi inode_unlock(udir); 6276b52243fSMiklos Szeredi 628e9be9d5eSMiklos Szeredi if (err) 6296b52243fSMiklos Szeredi goto out_dput; 630e9be9d5eSMiklos Szeredi 6310c288874SVivek Goyal if (!c->metacopy) 6320c288874SVivek Goyal ovl_set_upperdata(d_inode(c->dentry)); 6336b52243fSMiklos Szeredi ovl_inode_update(d_inode(c->dentry), temp); 634b79e05aaSAmir Goldstein 6356b52243fSMiklos Szeredi return 0; 6366b52243fSMiklos Szeredi 6376b52243fSMiklos Szeredi out_dput: 638e85f82ffSMiklos Szeredi dput(temp); 639e9be9d5eSMiklos Szeredi return err; 640e9be9d5eSMiklos Szeredi } 641e9be9d5eSMiklos Szeredi 642e9be9d5eSMiklos Szeredi /* 643e9be9d5eSMiklos Szeredi * Copy up a single dentry 644e9be9d5eSMiklos Szeredi * 645a6c60655SMiklos Szeredi * All renames start with copy up of source if necessary. The actual 646a6c60655SMiklos Szeredi * rename will only proceed once the copy up was successful. Copy up uses 647a6c60655SMiklos Szeredi * upper parent i_mutex for exclusion. Since rename can change d_parent it 648a6c60655SMiklos Szeredi * is possible that the copy up will lock the old parent. At that point 649a6c60655SMiklos Szeredi * the file will have already been copied up anyway. 650e9be9d5eSMiklos Szeredi */ 651a6fb235aSMiklos Szeredi static int ovl_do_copy_up(struct ovl_copy_up_ctx *c) 652e9be9d5eSMiklos Szeredi { 653e9be9d5eSMiklos Szeredi int err; 65423f0ab13SMiklos Szeredi struct ovl_fs *ofs = c->dentry->d_sb->s_fs_info; 655016b720fSAmir Goldstein bool to_index = false; 65659be0971SAmir Goldstein 657016b720fSAmir Goldstein /* 658016b720fSAmir Goldstein * Indexed non-dir is copied up directly to the index entry and then 659016b720fSAmir Goldstein * hardlinked to upper dir. Indexed dir is copied up to indexdir, 660016b720fSAmir Goldstein * then index entry is created and then copied up dir installed. 661016b720fSAmir Goldstein * Copying dir up to indexdir instead of workdir simplifies locking. 662016b720fSAmir Goldstein */ 663016b720fSAmir Goldstein if (ovl_need_index(c->dentry)) { 664016b720fSAmir Goldstein c->indexed = true; 665016b720fSAmir Goldstein if (S_ISDIR(c->stat.mode)) 666016b720fSAmir Goldstein c->workdir = ovl_indexdir(c->dentry->d_sb); 667016b720fSAmir Goldstein else 668016b720fSAmir Goldstein to_index = true; 669016b720fSAmir Goldstein } 670016b720fSAmir Goldstein 671016b720fSAmir Goldstein if (S_ISDIR(c->stat.mode) || c->stat.nlink == 1 || to_index) 67259be0971SAmir Goldstein c->origin = true; 67359be0971SAmir Goldstein 674016b720fSAmir Goldstein if (to_index) { 67559be0971SAmir Goldstein c->destdir = ovl_indexdir(c->dentry->d_sb); 67659be0971SAmir Goldstein err = ovl_get_index_name(c->lowerpath.dentry, &c->destname); 677f3a15685SAmir Goldstein if (err) 678f3a15685SAmir Goldstein return err; 679aa3ff3c1SAmir Goldstein } else if (WARN_ON(!c->parent)) { 680aa3ff3c1SAmir Goldstein /* Disconnected dentry must be copied up to index dir */ 681aa3ff3c1SAmir Goldstein return -EIO; 68259be0971SAmir Goldstein } else { 68359be0971SAmir Goldstein /* 68459be0971SAmir Goldstein * Mark parent "impure" because it may now contain non-pure 68559be0971SAmir Goldstein * upper 68659be0971SAmir Goldstein */ 68759be0971SAmir Goldstein err = ovl_set_impure(c->parent, c->destdir); 68859be0971SAmir Goldstein if (err) 68959be0971SAmir Goldstein return err; 69059be0971SAmir Goldstein } 691f3a15685SAmir Goldstein 69201ad3eb8SAmir Goldstein /* Should we copyup with O_TMPFILE or with workdir? */ 693b10cdcdcSAmir Goldstein if (S_ISREG(c->stat.mode) && ofs->tmpfile) 694b10cdcdcSAmir Goldstein err = ovl_copy_up_tmpfile(c); 695b10cdcdcSAmir Goldstein else 696b10cdcdcSAmir Goldstein err = ovl_copy_up_workdir(c); 697aa3ff3c1SAmir Goldstein if (err) 698aa3ff3c1SAmir Goldstein goto out; 699aa3ff3c1SAmir Goldstein 700aa3ff3c1SAmir Goldstein if (c->indexed) 70159be0971SAmir Goldstein ovl_set_flag(OVL_INDEX, d_inode(c->dentry)); 702016b720fSAmir Goldstein 703016b720fSAmir Goldstein if (to_index) { 704aa3ff3c1SAmir Goldstein /* Initialize nlink for copy up of disconnected dentry */ 705aa3ff3c1SAmir Goldstein err = ovl_set_nlink_upper(c->dentry); 706aa3ff3c1SAmir Goldstein } else { 70759be0971SAmir Goldstein struct inode *udir = d_inode(c->destdir); 70859be0971SAmir Goldstein 70959be0971SAmir Goldstein /* Restore timestamps on parent (best effort) */ 71059be0971SAmir Goldstein inode_lock(udir); 71159be0971SAmir Goldstein ovl_set_timestamps(c->destdir, &c->pstat); 71259be0971SAmir Goldstein inode_unlock(udir); 71359be0971SAmir Goldstein 71459be0971SAmir Goldstein ovl_dentry_set_upper_alias(c->dentry); 715fd210b7dSMiklos Szeredi } 716a6fb235aSMiklos Szeredi 717aa3ff3c1SAmir Goldstein out: 718aa3ff3c1SAmir Goldstein if (to_index) 719aa3ff3c1SAmir Goldstein kfree(c->destname.name); 720a6fb235aSMiklos Szeredi return err; 721a6fb235aSMiklos Szeredi } 722a6fb235aSMiklos Szeredi 72344d5bf10SVivek Goyal static bool ovl_need_meta_copy_up(struct dentry *dentry, umode_t mode, 72444d5bf10SVivek Goyal int flags) 72544d5bf10SVivek Goyal { 72644d5bf10SVivek Goyal struct ovl_fs *ofs = dentry->d_sb->s_fs_info; 72744d5bf10SVivek Goyal 72844d5bf10SVivek Goyal if (!ofs->config.metacopy) 72944d5bf10SVivek Goyal return false; 73044d5bf10SVivek Goyal 73144d5bf10SVivek Goyal if (!S_ISREG(mode)) 73244d5bf10SVivek Goyal return false; 73344d5bf10SVivek Goyal 73444d5bf10SVivek Goyal if (flags && ((OPEN_FMODE(flags) & FMODE_WRITE) || (flags & O_TRUNC))) 73544d5bf10SVivek Goyal return false; 73644d5bf10SVivek Goyal 73744d5bf10SVivek Goyal return true; 73844d5bf10SVivek Goyal } 73944d5bf10SVivek Goyal 7400c288874SVivek Goyal /* Copy up data of an inode which was copied up metadata only in the past. */ 7410c288874SVivek Goyal static int ovl_copy_up_meta_inode_data(struct ovl_copy_up_ctx *c) 7420c288874SVivek Goyal { 7434f93b426SVivek Goyal struct path upperpath, datapath; 7440c288874SVivek Goyal int err; 745993a0b2aSVivek Goyal char *capability = NULL; 746993a0b2aSVivek Goyal ssize_t uninitialized_var(cap_size); 7470c288874SVivek Goyal 7480c288874SVivek Goyal ovl_path_upper(c->dentry, &upperpath); 7490c288874SVivek Goyal if (WARN_ON(upperpath.dentry == NULL)) 7500c288874SVivek Goyal return -EIO; 7510c288874SVivek Goyal 7524f93b426SVivek Goyal ovl_path_lowerdata(c->dentry, &datapath); 7534f93b426SVivek Goyal if (WARN_ON(datapath.dentry == NULL)) 7544f93b426SVivek Goyal return -EIO; 7554f93b426SVivek Goyal 756993a0b2aSVivek Goyal if (c->stat.size) { 757993a0b2aSVivek Goyal err = cap_size = ovl_getxattr(upperpath.dentry, XATTR_NAME_CAPS, 758993a0b2aSVivek Goyal &capability, 0); 759993a0b2aSVivek Goyal if (err < 0 && err != -ENODATA) 760993a0b2aSVivek Goyal goto out; 761993a0b2aSVivek Goyal } 762993a0b2aSVivek Goyal 7634f93b426SVivek Goyal err = ovl_copy_up_data(&datapath, &upperpath, c->stat.size); 7640c288874SVivek Goyal if (err) 765993a0b2aSVivek Goyal goto out_free; 766993a0b2aSVivek Goyal 767993a0b2aSVivek Goyal /* 768993a0b2aSVivek Goyal * Writing to upper file will clear security.capability xattr. We 769993a0b2aSVivek Goyal * don't want that to happen for normal copy-up operation. 770993a0b2aSVivek Goyal */ 771993a0b2aSVivek Goyal if (capability) { 772993a0b2aSVivek Goyal err = ovl_do_setxattr(upperpath.dentry, XATTR_NAME_CAPS, 773993a0b2aSVivek Goyal capability, cap_size, 0); 774993a0b2aSVivek Goyal if (err) 775993a0b2aSVivek Goyal goto out_free; 776993a0b2aSVivek Goyal } 777993a0b2aSVivek Goyal 7780c288874SVivek Goyal 7790c288874SVivek Goyal err = vfs_removexattr(upperpath.dentry, OVL_XATTR_METACOPY); 7800c288874SVivek Goyal if (err) 781993a0b2aSVivek Goyal goto out_free; 7820c288874SVivek Goyal 7830c288874SVivek Goyal ovl_set_upperdata(d_inode(c->dentry)); 784993a0b2aSVivek Goyal out_free: 785993a0b2aSVivek Goyal kfree(capability); 786993a0b2aSVivek Goyal out: 7870c288874SVivek Goyal return err; 7880c288874SVivek Goyal } 7890c288874SVivek Goyal 790a6fb235aSMiklos Szeredi static int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry, 791a6fb235aSMiklos Szeredi int flags) 792a6fb235aSMiklos Szeredi { 793a6fb235aSMiklos Szeredi int err; 794a6fb235aSMiklos Szeredi DEFINE_DELAYED_CALL(done); 795a6fb235aSMiklos Szeredi struct path parentpath; 796a6fb235aSMiklos Szeredi struct ovl_copy_up_ctx ctx = { 797a6fb235aSMiklos Szeredi .parent = parent, 798a6fb235aSMiklos Szeredi .dentry = dentry, 799a6fb235aSMiklos Szeredi .workdir = ovl_workdir(dentry), 800a6fb235aSMiklos Szeredi }; 801a6fb235aSMiklos Szeredi 802a6fb235aSMiklos Szeredi if (WARN_ON(!ctx.workdir)) 803a6fb235aSMiklos Szeredi return -EROFS; 804a6fb235aSMiklos Szeredi 805a6fb235aSMiklos Szeredi ovl_path_lower(dentry, &ctx.lowerpath); 806a6fb235aSMiklos Szeredi err = vfs_getattr(&ctx.lowerpath, &ctx.stat, 807a6fb235aSMiklos Szeredi STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT); 808a6fb235aSMiklos Szeredi if (err) 809a6fb235aSMiklos Szeredi return err; 810a6fb235aSMiklos Szeredi 81144d5bf10SVivek Goyal ctx.metacopy = ovl_need_meta_copy_up(dentry, ctx.stat.mode, flags); 81244d5bf10SVivek Goyal 813aa3ff3c1SAmir Goldstein if (parent) { 814a6fb235aSMiklos Szeredi ovl_path_upper(parent, &parentpath); 81559be0971SAmir Goldstein ctx.destdir = parentpath.dentry; 81659be0971SAmir Goldstein ctx.destname = dentry->d_name; 817a6fb235aSMiklos Szeredi 818a6fb235aSMiklos Szeredi err = vfs_getattr(&parentpath, &ctx.pstat, 819aa3ff3c1SAmir Goldstein STATX_ATIME | STATX_MTIME, 820aa3ff3c1SAmir Goldstein AT_STATX_SYNC_AS_STAT); 821a6fb235aSMiklos Szeredi if (err) 822a6fb235aSMiklos Szeredi return err; 823aa3ff3c1SAmir Goldstein } 824a6fb235aSMiklos Szeredi 825a6fb235aSMiklos Szeredi /* maybe truncate regular file. this has no effect on dirs */ 826a6fb235aSMiklos Szeredi if (flags & O_TRUNC) 827a6fb235aSMiklos Szeredi ctx.stat.size = 0; 828a6fb235aSMiklos Szeredi 829a6fb235aSMiklos Szeredi if (S_ISLNK(ctx.stat.mode)) { 830a6fb235aSMiklos Szeredi ctx.link = vfs_get_link(ctx.lowerpath.dentry, &done); 831a6fb235aSMiklos Szeredi if (IS_ERR(ctx.link)) 832a6fb235aSMiklos Szeredi return PTR_ERR(ctx.link); 833a6fb235aSMiklos Szeredi } 834a6fb235aSMiklos Szeredi 8350c288874SVivek Goyal err = ovl_copy_up_start(dentry, flags); 836fd210b7dSMiklos Szeredi /* err < 0: interrupted, err > 0: raced with another copy-up */ 837fd210b7dSMiklos Szeredi if (unlikely(err)) { 838fd210b7dSMiklos Szeredi if (err > 0) 839fd210b7dSMiklos Szeredi err = 0; 840fd210b7dSMiklos Szeredi } else { 84159be0971SAmir Goldstein if (!ovl_dentry_upper(dentry)) 842a6fb235aSMiklos Szeredi err = ovl_do_copy_up(&ctx); 843aa3ff3c1SAmir Goldstein if (!err && parent && !ovl_dentry_has_upper_alias(dentry)) 844f4439de1SAmir Goldstein err = ovl_link_up(&ctx); 8450c288874SVivek Goyal if (!err && ovl_dentry_needs_data_copy_up_locked(dentry, flags)) 8460c288874SVivek Goyal err = ovl_copy_up_meta_inode_data(&ctx); 847fd210b7dSMiklos Szeredi ovl_copy_up_end(dentry); 848fd210b7dSMiklos Szeredi } 8497764235bSMiklos Szeredi do_delayed_call(&done); 850e9be9d5eSMiklos Szeredi 851e9be9d5eSMiklos Szeredi return err; 852e9be9d5eSMiklos Szeredi } 853e9be9d5eSMiklos Szeredi 8549aba6521SAmir Goldstein int ovl_copy_up_flags(struct dentry *dentry, int flags) 855e9be9d5eSMiklos Szeredi { 8568eac98b8SVivek Goyal int err = 0; 8578eac98b8SVivek Goyal const struct cred *old_cred = ovl_override_creds(dentry->d_sb); 858aa3ff3c1SAmir Goldstein bool disconnected = (dentry->d_flags & DCACHE_DISCONNECTED); 859aa3ff3c1SAmir Goldstein 860aa3ff3c1SAmir Goldstein /* 861aa3ff3c1SAmir Goldstein * With NFS export, copy up can get called for a disconnected non-dir. 862aa3ff3c1SAmir Goldstein * In this case, we will copy up lower inode to index dir without 863aa3ff3c1SAmir Goldstein * linking it to upper dir. 864aa3ff3c1SAmir Goldstein */ 865aa3ff3c1SAmir Goldstein if (WARN_ON(disconnected && d_is_dir(dentry))) 866aa3ff3c1SAmir Goldstein return -EIO; 867e9be9d5eSMiklos Szeredi 868e9be9d5eSMiklos Szeredi while (!err) { 869e9be9d5eSMiklos Szeredi struct dentry *next; 870aa3ff3c1SAmir Goldstein struct dentry *parent = NULL; 871e9be9d5eSMiklos Szeredi 8720c288874SVivek Goyal if (ovl_already_copied_up(dentry, flags)) 873e9be9d5eSMiklos Szeredi break; 874e9be9d5eSMiklos Szeredi 875e9be9d5eSMiklos Szeredi next = dget(dentry); 876e9be9d5eSMiklos Szeredi /* find the topmost dentry not yet copied up */ 877aa3ff3c1SAmir Goldstein for (; !disconnected;) { 878e9be9d5eSMiklos Szeredi parent = dget_parent(next); 879e9be9d5eSMiklos Szeredi 88059be0971SAmir Goldstein if (ovl_dentry_upper(parent)) 881e9be9d5eSMiklos Szeredi break; 882e9be9d5eSMiklos Szeredi 883e9be9d5eSMiklos Szeredi dput(next); 884e9be9d5eSMiklos Szeredi next = parent; 885e9be9d5eSMiklos Szeredi } 886e9be9d5eSMiklos Szeredi 887a6fb235aSMiklos Szeredi err = ovl_copy_up_one(parent, next, flags); 888e9be9d5eSMiklos Szeredi 889e9be9d5eSMiklos Szeredi dput(parent); 890e9be9d5eSMiklos Szeredi dput(next); 891e9be9d5eSMiklos Szeredi } 8928eac98b8SVivek Goyal revert_creds(old_cred); 893e9be9d5eSMiklos Szeredi 894e9be9d5eSMiklos Szeredi return err; 895e9be9d5eSMiklos Szeredi } 8969aba6521SAmir Goldstein 897d6eac039SVivek Goyal static bool ovl_open_need_copy_up(struct dentry *dentry, int flags) 898d6eac039SVivek Goyal { 899d6eac039SVivek Goyal /* Copy up of disconnected dentry does not set upper alias */ 9000c288874SVivek Goyal if (ovl_already_copied_up(dentry, flags)) 901d6eac039SVivek Goyal return false; 902d6eac039SVivek Goyal 903d6eac039SVivek Goyal if (special_file(d_inode(dentry)->i_mode)) 904d6eac039SVivek Goyal return false; 905d6eac039SVivek Goyal 9060c288874SVivek Goyal if (!ovl_open_flags_need_copy_up(flags)) 907d6eac039SVivek Goyal return false; 908d6eac039SVivek Goyal 909d6eac039SVivek Goyal return true; 910d6eac039SVivek Goyal } 911d6eac039SVivek Goyal 912d6eac039SVivek Goyal int ovl_open_maybe_copy_up(struct dentry *dentry, unsigned int file_flags) 913d6eac039SVivek Goyal { 914d6eac039SVivek Goyal int err = 0; 915d6eac039SVivek Goyal 916d6eac039SVivek Goyal if (ovl_open_need_copy_up(dentry, file_flags)) { 917d6eac039SVivek Goyal err = ovl_want_write(dentry); 918d6eac039SVivek Goyal if (!err) { 919d6eac039SVivek Goyal err = ovl_copy_up_flags(dentry, file_flags); 920d6eac039SVivek Goyal ovl_drop_write(dentry); 921d6eac039SVivek Goyal } 922d6eac039SVivek Goyal } 923d6eac039SVivek Goyal 924d6eac039SVivek Goyal return err; 925d6eac039SVivek Goyal } 926d6eac039SVivek Goyal 927d1e6f6a9SVivek Goyal int ovl_copy_up_with_data(struct dentry *dentry) 928d1e6f6a9SVivek Goyal { 929d1e6f6a9SVivek Goyal return ovl_copy_up_flags(dentry, O_WRONLY); 930d1e6f6a9SVivek Goyal } 931d1e6f6a9SVivek Goyal 9329aba6521SAmir Goldstein int ovl_copy_up(struct dentry *dentry) 9339aba6521SAmir Goldstein { 9349aba6521SAmir Goldstein return ovl_copy_up_flags(dentry, 0); 9359aba6521SAmir Goldstein } 936