Back to home page

OSCL-LXR
 
 

     

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  *  linux/fs/hfsplus/dir.c
0004  *
0005  * Copyright (C) 2001
0006  * Brad Boyer (flar@allandria.com)
0007  * (C) 2003 Ardis Technologies <roman@ardistech.com>
0008  *
0009  * Handling of directories
0010  */
0011 
0012 #include <linux/errno.h>
0013 #include <linux/fs.h>
0014 #include <linux/slab.h>
0015 #include <linux/random.h>
0016 #include <linux/nls.h>
0017 
0018 #include "hfsplus_fs.h"
0019 #include "hfsplus_raw.h"
0020 #include "xattr.h"
0021 
0022 static inline void hfsplus_instantiate(struct dentry *dentry,
0023                        struct inode *inode, u32 cnid)
0024 {
0025     dentry->d_fsdata = (void *)(unsigned long)cnid;
0026     d_instantiate(dentry, inode);
0027 }
0028 
0029 /* Find the entry inside dir named dentry->d_name */
0030 static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry,
0031                      unsigned int flags)
0032 {
0033     struct inode *inode = NULL;
0034     struct hfs_find_data fd;
0035     struct super_block *sb;
0036     hfsplus_cat_entry entry;
0037     int err;
0038     u32 cnid, linkid = 0;
0039     u16 type;
0040 
0041     sb = dir->i_sb;
0042 
0043     dentry->d_fsdata = NULL;
0044     err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
0045     if (err)
0046         return ERR_PTR(err);
0047     err = hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino,
0048             &dentry->d_name);
0049     if (unlikely(err < 0))
0050         goto fail;
0051 again:
0052     err = hfs_brec_read(&fd, &entry, sizeof(entry));
0053     if (err) {
0054         if (err == -ENOENT) {
0055             hfs_find_exit(&fd);
0056             /* No such entry */
0057             inode = NULL;
0058             goto out;
0059         }
0060         goto fail;
0061     }
0062     type = be16_to_cpu(entry.type);
0063     if (type == HFSPLUS_FOLDER) {
0064         if (fd.entrylength < sizeof(struct hfsplus_cat_folder)) {
0065             err = -EIO;
0066             goto fail;
0067         }
0068         cnid = be32_to_cpu(entry.folder.id);
0069         dentry->d_fsdata = (void *)(unsigned long)cnid;
0070     } else if (type == HFSPLUS_FILE) {
0071         if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
0072             err = -EIO;
0073             goto fail;
0074         }
0075         cnid = be32_to_cpu(entry.file.id);
0076         if (entry.file.user_info.fdType ==
0077                 cpu_to_be32(HFSP_HARDLINK_TYPE) &&
0078                 entry.file.user_info.fdCreator ==
0079                 cpu_to_be32(HFSP_HFSPLUS_CREATOR) &&
0080                 HFSPLUS_SB(sb)->hidden_dir &&
0081                 (entry.file.create_date ==
0082                     HFSPLUS_I(HFSPLUS_SB(sb)->hidden_dir)->
0083                         create_date ||
0084                 entry.file.create_date ==
0085                     HFSPLUS_I(d_inode(sb->s_root))->
0086                         create_date)) {
0087             struct qstr str;
0088             char name[32];
0089 
0090             if (dentry->d_fsdata) {
0091                 /*
0092                  * We found a link pointing to another link,
0093                  * so ignore it and treat it as regular file.
0094                  */
0095                 cnid = (unsigned long)dentry->d_fsdata;
0096                 linkid = 0;
0097             } else {
0098                 dentry->d_fsdata = (void *)(unsigned long)cnid;
0099                 linkid =
0100                     be32_to_cpu(entry.file.permissions.dev);
0101                 str.len = sprintf(name, "iNode%d", linkid);
0102                 str.name = name;
0103                 err = hfsplus_cat_build_key(sb, fd.search_key,
0104                     HFSPLUS_SB(sb)->hidden_dir->i_ino,
0105                     &str);
0106                 if (unlikely(err < 0))
0107                     goto fail;
0108                 goto again;
0109             }
0110         } else if (!dentry->d_fsdata)
0111             dentry->d_fsdata = (void *)(unsigned long)cnid;
0112     } else {
0113         pr_err("invalid catalog entry type in lookup\n");
0114         err = -EIO;
0115         goto fail;
0116     }
0117     hfs_find_exit(&fd);
0118     inode = hfsplus_iget(dir->i_sb, cnid);
0119     if (IS_ERR(inode))
0120         return ERR_CAST(inode);
0121     if (S_ISREG(inode->i_mode))
0122         HFSPLUS_I(inode)->linkid = linkid;
0123 out:
0124     return d_splice_alias(inode, dentry);
0125 fail:
0126     hfs_find_exit(&fd);
0127     return ERR_PTR(err);
0128 }
0129 
0130 static int hfsplus_readdir(struct file *file, struct dir_context *ctx)
0131 {
0132     struct inode *inode = file_inode(file);
0133     struct super_block *sb = inode->i_sb;
0134     int len, err;
0135     char *strbuf;
0136     hfsplus_cat_entry entry;
0137     struct hfs_find_data fd;
0138     struct hfsplus_readdir_data *rd;
0139     u16 type;
0140 
0141     if (file->f_pos >= inode->i_size)
0142         return 0;
0143 
0144     err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
0145     if (err)
0146         return err;
0147     strbuf = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_MAX_STRLEN + 1, GFP_KERNEL);
0148     if (!strbuf) {
0149         err = -ENOMEM;
0150         goto out;
0151     }
0152     hfsplus_cat_build_key_with_cnid(sb, fd.search_key, inode->i_ino);
0153     err = hfs_brec_find(&fd, hfs_find_rec_by_key);
0154     if (err)
0155         goto out;
0156 
0157     if (ctx->pos == 0) {
0158         /* This is completely artificial... */
0159         if (!dir_emit_dot(file, ctx))
0160             goto out;
0161         ctx->pos = 1;
0162     }
0163     if (ctx->pos == 1) {
0164         if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
0165             err = -EIO;
0166             goto out;
0167         }
0168 
0169         hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
0170             fd.entrylength);
0171         if (be16_to_cpu(entry.type) != HFSPLUS_FOLDER_THREAD) {
0172             pr_err("bad catalog folder thread\n");
0173             err = -EIO;
0174             goto out;
0175         }
0176         if (fd.entrylength < HFSPLUS_MIN_THREAD_SZ) {
0177             pr_err("truncated catalog thread\n");
0178             err = -EIO;
0179             goto out;
0180         }
0181         if (!dir_emit(ctx, "..", 2,
0182                 be32_to_cpu(entry.thread.parentID), DT_DIR))
0183             goto out;
0184         ctx->pos = 2;
0185     }
0186     if (ctx->pos >= inode->i_size)
0187         goto out;
0188     err = hfs_brec_goto(&fd, ctx->pos - 1);
0189     if (err)
0190         goto out;
0191     for (;;) {
0192         if (be32_to_cpu(fd.key->cat.parent) != inode->i_ino) {
0193             pr_err("walked past end of dir\n");
0194             err = -EIO;
0195             goto out;
0196         }
0197 
0198         if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
0199             err = -EIO;
0200             goto out;
0201         }
0202 
0203         hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
0204             fd.entrylength);
0205         type = be16_to_cpu(entry.type);
0206         len = NLS_MAX_CHARSET_SIZE * HFSPLUS_MAX_STRLEN;
0207         err = hfsplus_uni2asc(sb, &fd.key->cat.name, strbuf, &len);
0208         if (err)
0209             goto out;
0210         if (type == HFSPLUS_FOLDER) {
0211             if (fd.entrylength <
0212                     sizeof(struct hfsplus_cat_folder)) {
0213                 pr_err("small dir entry\n");
0214                 err = -EIO;
0215                 goto out;
0216             }
0217             if (HFSPLUS_SB(sb)->hidden_dir &&
0218                 HFSPLUS_SB(sb)->hidden_dir->i_ino ==
0219                     be32_to_cpu(entry.folder.id))
0220                 goto next;
0221             if (!dir_emit(ctx, strbuf, len,
0222                     be32_to_cpu(entry.folder.id), DT_DIR))
0223                 break;
0224         } else if (type == HFSPLUS_FILE) {
0225             u16 mode;
0226             unsigned type = DT_UNKNOWN;
0227 
0228             if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
0229                 pr_err("small file entry\n");
0230                 err = -EIO;
0231                 goto out;
0232             }
0233 
0234             mode = be16_to_cpu(entry.file.permissions.mode);
0235             if (S_ISREG(mode))
0236                 type = DT_REG;
0237             else if (S_ISLNK(mode))
0238                 type = DT_LNK;
0239             else if (S_ISFIFO(mode))
0240                 type = DT_FIFO;
0241             else if (S_ISCHR(mode))
0242                 type = DT_CHR;
0243             else if (S_ISBLK(mode))
0244                 type = DT_BLK;
0245             else if (S_ISSOCK(mode))
0246                 type = DT_SOCK;
0247 
0248             if (!dir_emit(ctx, strbuf, len,
0249                       be32_to_cpu(entry.file.id), type))
0250                 break;
0251         } else {
0252             pr_err("bad catalog entry type\n");
0253             err = -EIO;
0254             goto out;
0255         }
0256 next:
0257         ctx->pos++;
0258         if (ctx->pos >= inode->i_size)
0259             goto out;
0260         err = hfs_brec_goto(&fd, 1);
0261         if (err)
0262             goto out;
0263     }
0264     rd = file->private_data;
0265     if (!rd) {
0266         rd = kmalloc(sizeof(struct hfsplus_readdir_data), GFP_KERNEL);
0267         if (!rd) {
0268             err = -ENOMEM;
0269             goto out;
0270         }
0271         file->private_data = rd;
0272         rd->file = file;
0273         spin_lock(&HFSPLUS_I(inode)->open_dir_lock);
0274         list_add(&rd->list, &HFSPLUS_I(inode)->open_dir_list);
0275         spin_unlock(&HFSPLUS_I(inode)->open_dir_lock);
0276     }
0277     /*
0278      * Can be done after the list insertion; exclusion with
0279      * hfsplus_delete_cat() is provided by directory lock.
0280      */
0281     memcpy(&rd->key, fd.key, sizeof(struct hfsplus_cat_key));
0282 out:
0283     kfree(strbuf);
0284     hfs_find_exit(&fd);
0285     return err;
0286 }
0287 
0288 static int hfsplus_dir_release(struct inode *inode, struct file *file)
0289 {
0290     struct hfsplus_readdir_data *rd = file->private_data;
0291     if (rd) {
0292         spin_lock(&HFSPLUS_I(inode)->open_dir_lock);
0293         list_del(&rd->list);
0294         spin_unlock(&HFSPLUS_I(inode)->open_dir_lock);
0295         kfree(rd);
0296     }
0297     return 0;
0298 }
0299 
0300 static int hfsplus_link(struct dentry *src_dentry, struct inode *dst_dir,
0301             struct dentry *dst_dentry)
0302 {
0303     struct hfsplus_sb_info *sbi = HFSPLUS_SB(dst_dir->i_sb);
0304     struct inode *inode = d_inode(src_dentry);
0305     struct inode *src_dir = d_inode(src_dentry->d_parent);
0306     struct qstr str;
0307     char name[32];
0308     u32 cnid, id;
0309     int res;
0310 
0311     if (HFSPLUS_IS_RSRC(inode))
0312         return -EPERM;
0313     if (!S_ISREG(inode->i_mode))
0314         return -EPERM;
0315 
0316     mutex_lock(&sbi->vh_mutex);
0317     if (inode->i_ino == (u32)(unsigned long)src_dentry->d_fsdata) {
0318         for (;;) {
0319             get_random_bytes(&id, sizeof(cnid));
0320             id &= 0x3fffffff;
0321             str.name = name;
0322             str.len = sprintf(name, "iNode%d", id);
0323             res = hfsplus_rename_cat(inode->i_ino,
0324                          src_dir, &src_dentry->d_name,
0325                          sbi->hidden_dir, &str);
0326             if (!res)
0327                 break;
0328             if (res != -EEXIST)
0329                 goto out;
0330         }
0331         HFSPLUS_I(inode)->linkid = id;
0332         cnid = sbi->next_cnid++;
0333         src_dentry->d_fsdata = (void *)(unsigned long)cnid;
0334         res = hfsplus_create_cat(cnid, src_dir,
0335             &src_dentry->d_name, inode);
0336         if (res)
0337             /* panic? */
0338             goto out;
0339         sbi->file_count++;
0340     }
0341     cnid = sbi->next_cnid++;
0342     res = hfsplus_create_cat(cnid, dst_dir, &dst_dentry->d_name, inode);
0343     if (res)
0344         goto out;
0345 
0346     inc_nlink(inode);
0347     hfsplus_instantiate(dst_dentry, inode, cnid);
0348     ihold(inode);
0349     inode->i_ctime = current_time(inode);
0350     mark_inode_dirty(inode);
0351     sbi->file_count++;
0352     hfsplus_mark_mdb_dirty(dst_dir->i_sb);
0353 out:
0354     mutex_unlock(&sbi->vh_mutex);
0355     return res;
0356 }
0357 
0358 static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
0359 {
0360     struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
0361     struct inode *inode = d_inode(dentry);
0362     struct qstr str;
0363     char name[32];
0364     u32 cnid;
0365     int res;
0366 
0367     if (HFSPLUS_IS_RSRC(inode))
0368         return -EPERM;
0369 
0370     mutex_lock(&sbi->vh_mutex);
0371     cnid = (u32)(unsigned long)dentry->d_fsdata;
0372     if (inode->i_ino == cnid &&
0373         atomic_read(&HFSPLUS_I(inode)->opencnt)) {
0374         str.name = name;
0375         str.len = sprintf(name, "temp%lu", inode->i_ino);
0376         res = hfsplus_rename_cat(inode->i_ino,
0377                      dir, &dentry->d_name,
0378                      sbi->hidden_dir, &str);
0379         if (!res) {
0380             inode->i_flags |= S_DEAD;
0381             drop_nlink(inode);
0382         }
0383         goto out;
0384     }
0385     res = hfsplus_delete_cat(cnid, dir, &dentry->d_name);
0386     if (res)
0387         goto out;
0388 
0389     if (inode->i_nlink > 0)
0390         drop_nlink(inode);
0391     if (inode->i_ino == cnid)
0392         clear_nlink(inode);
0393     if (!inode->i_nlink) {
0394         if (inode->i_ino != cnid) {
0395             sbi->file_count--;
0396             if (!atomic_read(&HFSPLUS_I(inode)->opencnt)) {
0397                 res = hfsplus_delete_cat(inode->i_ino,
0398                              sbi->hidden_dir,
0399                              NULL);
0400                 if (!res)
0401                     hfsplus_delete_inode(inode);
0402             } else
0403                 inode->i_flags |= S_DEAD;
0404         } else
0405             hfsplus_delete_inode(inode);
0406     } else
0407         sbi->file_count--;
0408     inode->i_ctime = current_time(inode);
0409     mark_inode_dirty(inode);
0410 out:
0411     mutex_unlock(&sbi->vh_mutex);
0412     return res;
0413 }
0414 
0415 static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry)
0416 {
0417     struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
0418     struct inode *inode = d_inode(dentry);
0419     int res;
0420 
0421     if (inode->i_size != 2)
0422         return -ENOTEMPTY;
0423 
0424     mutex_lock(&sbi->vh_mutex);
0425     res = hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
0426     if (res)
0427         goto out;
0428     clear_nlink(inode);
0429     inode->i_ctime = current_time(inode);
0430     hfsplus_delete_inode(inode);
0431     mark_inode_dirty(inode);
0432 out:
0433     mutex_unlock(&sbi->vh_mutex);
0434     return res;
0435 }
0436 
0437 static int hfsplus_symlink(struct user_namespace *mnt_userns, struct inode *dir,
0438                struct dentry *dentry, const char *symname)
0439 {
0440     struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
0441     struct inode *inode;
0442     int res = -ENOMEM;
0443 
0444     mutex_lock(&sbi->vh_mutex);
0445     inode = hfsplus_new_inode(dir->i_sb, dir, S_IFLNK | S_IRWXUGO);
0446     if (!inode)
0447         goto out;
0448 
0449     res = page_symlink(inode, symname, strlen(symname) + 1);
0450     if (res)
0451         goto out_err;
0452 
0453     res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
0454     if (res)
0455         goto out_err;
0456 
0457     res = hfsplus_init_security(inode, dir, &dentry->d_name);
0458     if (res == -EOPNOTSUPP)
0459         res = 0; /* Operation is not supported. */
0460     else if (res) {
0461         /* Try to delete anyway without error analysis. */
0462         hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
0463         goto out_err;
0464     }
0465 
0466     hfsplus_instantiate(dentry, inode, inode->i_ino);
0467     mark_inode_dirty(inode);
0468     goto out;
0469 
0470 out_err:
0471     clear_nlink(inode);
0472     hfsplus_delete_inode(inode);
0473     iput(inode);
0474 out:
0475     mutex_unlock(&sbi->vh_mutex);
0476     return res;
0477 }
0478 
0479 static int hfsplus_mknod(struct user_namespace *mnt_userns, struct inode *dir,
0480              struct dentry *dentry, umode_t mode, dev_t rdev)
0481 {
0482     struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
0483     struct inode *inode;
0484     int res = -ENOMEM;
0485 
0486     mutex_lock(&sbi->vh_mutex);
0487     inode = hfsplus_new_inode(dir->i_sb, dir, mode);
0488     if (!inode)
0489         goto out;
0490 
0491     if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode))
0492         init_special_inode(inode, mode, rdev);
0493 
0494     res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
0495     if (res)
0496         goto failed_mknod;
0497 
0498     res = hfsplus_init_security(inode, dir, &dentry->d_name);
0499     if (res == -EOPNOTSUPP)
0500         res = 0; /* Operation is not supported. */
0501     else if (res) {
0502         /* Try to delete anyway without error analysis. */
0503         hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
0504         goto failed_mknod;
0505     }
0506 
0507     hfsplus_instantiate(dentry, inode, inode->i_ino);
0508     mark_inode_dirty(inode);
0509     goto out;
0510 
0511 failed_mknod:
0512     clear_nlink(inode);
0513     hfsplus_delete_inode(inode);
0514     iput(inode);
0515 out:
0516     mutex_unlock(&sbi->vh_mutex);
0517     return res;
0518 }
0519 
0520 static int hfsplus_create(struct user_namespace *mnt_userns, struct inode *dir,
0521               struct dentry *dentry, umode_t mode, bool excl)
0522 {
0523     return hfsplus_mknod(&init_user_ns, dir, dentry, mode, 0);
0524 }
0525 
0526 static int hfsplus_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
0527              struct dentry *dentry, umode_t mode)
0528 {
0529     return hfsplus_mknod(&init_user_ns, dir, dentry, mode | S_IFDIR, 0);
0530 }
0531 
0532 static int hfsplus_rename(struct user_namespace *mnt_userns,
0533               struct inode *old_dir, struct dentry *old_dentry,
0534               struct inode *new_dir, struct dentry *new_dentry,
0535               unsigned int flags)
0536 {
0537     int res;
0538 
0539     if (flags & ~RENAME_NOREPLACE)
0540         return -EINVAL;
0541 
0542     /* Unlink destination if it already exists */
0543     if (d_really_is_positive(new_dentry)) {
0544         if (d_is_dir(new_dentry))
0545             res = hfsplus_rmdir(new_dir, new_dentry);
0546         else
0547             res = hfsplus_unlink(new_dir, new_dentry);
0548         if (res)
0549             return res;
0550     }
0551 
0552     res = hfsplus_rename_cat((u32)(unsigned long)old_dentry->d_fsdata,
0553                  old_dir, &old_dentry->d_name,
0554                  new_dir, &new_dentry->d_name);
0555     if (!res)
0556         new_dentry->d_fsdata = old_dentry->d_fsdata;
0557     return res;
0558 }
0559 
0560 const struct inode_operations hfsplus_dir_inode_operations = {
0561     .lookup         = hfsplus_lookup,
0562     .create         = hfsplus_create,
0563     .link           = hfsplus_link,
0564     .unlink         = hfsplus_unlink,
0565     .mkdir          = hfsplus_mkdir,
0566     .rmdir          = hfsplus_rmdir,
0567     .symlink        = hfsplus_symlink,
0568     .mknod          = hfsplus_mknod,
0569     .rename         = hfsplus_rename,
0570     .getattr        = hfsplus_getattr,
0571     .listxattr      = hfsplus_listxattr,
0572     .fileattr_get       = hfsplus_fileattr_get,
0573     .fileattr_set       = hfsplus_fileattr_set,
0574 };
0575 
0576 const struct file_operations hfsplus_dir_operations = {
0577     .fsync      = hfsplus_file_fsync,
0578     .read       = generic_read_dir,
0579     .iterate_shared = hfsplus_readdir,
0580     .unlocked_ioctl = hfsplus_ioctl,
0581     .llseek     = generic_file_llseek,
0582     .release    = hfsplus_dir_release,
0583 };
[ Source navigation ] [ Diff markup ] [ Identifier search ] [ general search ]

This page was automatically generated by the 2.1.0 LXR engine.

The LXR team
Valid CSS 2.1! Valid HTML 4.01!