diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-05 01:03:05 +0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-05 01:03:05 +0400 |
commit | 7df934526c0b3775613502dcd19ab6d2da8cce1e (patch) | |
tree | 01e6a4ea20c676228f4acefc6ae776d2e52072db | |
parent | 3c83e61e67256e0bb08c46cc2db43b58fd617251 (diff) | |
parent | bd42998a6bcb9b1708dac9ca9876e3d304c16f3d (diff) | |
download | linux-7df934526c0b3775613502dcd19ab6d2da8cce1e.tar.xz |
Merge branch 'cross-rename' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull renameat2 system call from Miklos Szeredi:
"This adds a new syscall, renameat2(), which is the same as renameat()
but with a flags argument.
The purpose of extending rename is to add cross-rename, a symmetric
variant of rename, which exchanges the two files. This allows
interesting things, which were not possible before, for example
atomically replacing a directory tree with a symlink, etc... This
also allows overlayfs and friends to operate on whiteouts atomically.
Andy Lutomirski also suggested a "noreplace" flag, which disables the
overwriting behavior of rename.
These two flags, RENAME_EXCHANGE and RENAME_NOREPLACE are only
implemented for ext4 as an example and for testing"
* 'cross-rename' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ext4: add cross rename support
ext4: rename: split out helper functions
ext4: rename: move EMLINK check up
ext4: rename: create ext4_renament structure for local vars
vfs: add cross-rename
vfs: lock_two_nondirectories: allow directory args
security: add flags to rename hooks
vfs: add RENAME_NOREPLACE flag
vfs: add renameat2 syscall
vfs: rename: use common code for dir and non-dir
vfs: rename: move d_move() up
vfs: add d_is_dir()
-rw-r--r-- | Documentation/filesystems/Locking | 6 | ||||
-rw-r--r-- | Documentation/filesystems/vfs.txt | 16 | ||||
-rw-r--r-- | arch/x86/syscalls/syscall_64.tbl | 1 | ||||
-rw-r--r-- | drivers/staging/lustre/lustre/include/linux/lustre_compat25.h | 4 | ||||
-rw-r--r-- | drivers/staging/lustre/lustre/lvfs/lvfs_linux.c | 2 | ||||
-rw-r--r-- | fs/cachefiles/namei.c | 4 | ||||
-rw-r--r-- | fs/dcache.c | 50 | ||||
-rw-r--r-- | fs/ecryptfs/inode.c | 2 | ||||
-rw-r--r-- | fs/ext4/namei.c | 480 | ||||
-rw-r--r-- | fs/inode.c | 25 | ||||
-rw-r--r-- | fs/namei.c | 315 | ||||
-rw-r--r-- | fs/nfsd/vfs.c | 2 | ||||
-rw-r--r-- | include/linux/dcache.h | 8 | ||||
-rw-r--r-- | include/linux/fs.h | 4 | ||||
-rw-r--r-- | include/linux/security.h | 12 | ||||
-rw-r--r-- | include/uapi/linux/fs.h | 3 | ||||
-rw-r--r-- | security/security.c | 22 |
17 files changed, 643 insertions, 313 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 5b0c083d7c0e..f424e0e5b46b 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -47,6 +47,8 @@ prototypes: int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t); int (*rename) (struct inode *, struct dentry *, struct inode *, struct dentry *); + int (*rename2) (struct inode *, struct dentry *, + struct inode *, struct dentry *, unsigned int); int (*readlink) (struct dentry *, char __user *,int); void * (*follow_link) (struct dentry *, struct nameidata *); void (*put_link) (struct dentry *, struct nameidata *, void *); @@ -78,6 +80,7 @@ mkdir: yes unlink: yes (both) rmdir: yes (both) (see below) rename: yes (all) (see below) +rename2: yes (all) (see below) readlink: no follow_link: no put_link: no @@ -96,7 +99,8 @@ tmpfile: no Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on victim. - cross-directory ->rename() has (per-superblock) ->s_vfs_rename_sem. + cross-directory ->rename() and rename2() has (per-superblock) +->s_vfs_rename_sem. See Documentation/filesystems/directory-locking for more detailed discussion of the locking scheme for directory operations. diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index c53784c119c8..94eb86287bcb 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -347,6 +347,8 @@ struct inode_operations { int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t); int (*rename) (struct inode *, struct dentry *, struct inode *, struct dentry *); + int (*rename2) (struct inode *, struct dentry *, + struct inode *, struct dentry *, unsigned int); int (*readlink) (struct dentry *, char __user *,int); void * (*follow_link) (struct dentry *, struct nameidata *); void (*put_link) (struct dentry *, struct nameidata *, void *); @@ -414,6 +416,20 @@ otherwise noted. rename: called by the rename(2) system call to rename the object to have the parent and name given by the second inode and dentry. + rename2: this has an additional flags argument compared to rename. + If no flags are supported by the filesystem then this method + need not be implemented. If some flags are supported then the + filesystem must return -EINVAL for any unsupported or unknown + flags. Currently the following flags are implemented: + (1) RENAME_NOREPLACE: this flag indicates that if the target + of the rename exists the rename should fail with -EEXIST + instead of replacing the target. The VFS already checks for + existence, so for local filesystems the RENAME_NOREPLACE + implementation is equivalent to plain rename. + (2) RENAME_EXCHANGE: exchange source and target. Both must + exist; this is checked by the VFS. Unlike plain rename, + source and target may be of different type. + readlink: called by the readlink(2) system call. Only required if you want to support reading symbolic links diff --git a/arch/x86/syscalls/syscall_64.tbl b/arch/x86/syscalls/syscall_64.tbl index a12bddc7ccea..04376ac3d9ef 100644 --- a/arch/x86/syscalls/syscall_64.tbl +++ b/arch/x86/syscalls/syscall_64.tbl @@ -322,6 +322,7 @@ 313 common finit_module sys_finit_module 314 common sched_setattr sys_sched_setattr 315 common sched_getattr sys_sched_getattr +316 common renameat2 sys_renameat2 # # x32-specific system call numbers start at 512 to avoid cache impact diff --git a/drivers/staging/lustre/lustre/include/linux/lustre_compat25.h b/drivers/staging/lustre/lustre/include/linux/lustre_compat25.h index eefdb8d061b1..81cc7a0134bb 100644 --- a/drivers/staging/lustre/lustre/include/linux/lustre_compat25.h +++ b/drivers/staging/lustre/lustre/include/linux/lustre_compat25.h @@ -105,8 +105,8 @@ static inline void ll_set_fs_pwd(struct fs_struct *fs, struct vfsmount *mnt, #define ll_vfs_unlink(inode,entry,mnt) vfs_unlink(inode,entry) #define ll_vfs_mknod(dir,entry,mnt,mode,dev) vfs_mknod(dir,entry,mode,dev) #define ll_security_inode_unlink(dir,entry,mnt) security_inode_unlink(dir,entry) -#define ll_vfs_rename(old,old_dir,mnt,new,new_dir,mnt1,delegated_inode) \ - vfs_rename(old,old_dir,new,new_dir,delegated_inode) +#define ll_vfs_rename(old, old_dir, mnt, new, new_dir, mnt1) \ + vfs_rename(old, old_dir, new, new_dir, NULL, 0) #define cfs_bio_io_error(a,b) bio_io_error((a)) #define cfs_bio_endio(a,b,c) bio_endio((a),(c)) diff --git a/drivers/staging/lustre/lustre/lvfs/lvfs_linux.c b/drivers/staging/lustre/lustre/lvfs/lvfs_linux.c index e44b7a532de7..374a9b78e1d2 100644 --- a/drivers/staging/lustre/lustre/lvfs/lvfs_linux.c +++ b/drivers/staging/lustre/lustre/lvfs/lvfs_linux.c @@ -223,7 +223,7 @@ int lustre_rename(struct dentry *dir, struct vfsmount *mnt, GOTO(put_old, err = PTR_ERR(dchild_new)); err = ll_vfs_rename(dir->d_inode, dchild_old, mnt, - dir->d_inode, dchild_new, mnt, NULL); + dir->d_inode, dchild_new, mnt); dput(dchild_new); put_old: diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c index ca65f39dc8dc..6494d9f673aa 100644 --- a/fs/cachefiles/namei.c +++ b/fs/cachefiles/namei.c @@ -391,12 +391,12 @@ try_again: path.dentry = dir; path_to_graveyard.mnt = cache->mnt; path_to_graveyard.dentry = cache->graveyard; - ret = security_path_rename(&path, rep, &path_to_graveyard, grave); + ret = security_path_rename(&path, rep, &path_to_graveyard, grave, 0); if (ret < 0) { cachefiles_io_error(cache, "Rename security error %d", ret); } else { ret = vfs_rename(dir->d_inode, rep, - cache->graveyard->d_inode, grave, NULL); + cache->graveyard->d_inode, grave, NULL, 0); if (ret != 0 && ret != -ENOMEM) cachefiles_io_error(cache, "Rename failed with error %d", ret); diff --git a/fs/dcache.c b/fs/dcache.c index ca02c13a84aa..66cba5a8a346 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -2483,12 +2483,14 @@ static void switch_names(struct dentry *dentry, struct dentry *target) dentry->d_name.name = dentry->d_iname; } else { /* - * Both are internal. Just copy target to dentry + * Both are internal. */ - memcpy(dentry->d_iname, target->d_name.name, - target->d_name.len + 1); - dentry->d_name.len = target->d_name.len; - return; + unsigned int i; + BUILD_BUG_ON(!IS_ALIGNED(DNAME_INLINE_LEN, sizeof(long))); + for (i = 0; i < DNAME_INLINE_LEN / sizeof(long); i++) { + swap(((long *) &dentry->d_iname)[i], + ((long *) &target->d_iname)[i]); + } } } swap(dentry->d_name.len, target->d_name.len); @@ -2545,13 +2547,15 @@ static void dentry_unlock_parents_for_move(struct dentry *dentry, * __d_move - move a dentry * @dentry: entry to move * @target: new dentry + * @exchange: exchange the two dentries * * Update the dcache to reflect the move of a file name. Negative * dcache entries should not be moved in this way. Caller must hold * rename_lock, the i_mutex of the source and target directories, * and the sb->s_vfs_rename_mutex if they differ. See lock_rename(). */ -static void __d_move(struct dentry * dentry, struct dentry * target) +static void __d_move(struct dentry *dentry, struct dentry *target, + bool exchange) { if (!dentry->d_inode) printk(KERN_WARNING "VFS: moving negative dcache entry\n"); @@ -2573,8 +2577,15 @@ static void __d_move(struct dentry * dentry, struct dentry * target) __d_drop(dentry); __d_rehash(dentry, d_hash(target->d_parent, target->d_name.hash)); - /* Unhash the target: dput() will then get rid of it */ + /* + * Unhash the target (d_delete() is not usable here). If exchanging + * the two dentries, then rehash onto the other's hash queue. + */ __d_drop(target); + if (exchange) { + __d_rehash(target, + d_hash(dentry->d_parent, dentry->d_name.hash)); + } list_del(&dentry->d_u.d_child); list_del(&target->d_u.d_child); @@ -2601,6 +2612,8 @@ static void __d_move(struct dentry * dentry, struct dentry * target) write_seqcount_end(&dentry->d_seq); dentry_unlock_parents_for_move(dentry, target); + if (exchange) + fsnotify_d_move(target); spin_unlock(&target->d_lock); fsnotify_d_move(dentry); spin_unlock(&dentry->d_lock); @@ -2618,11 +2631,30 @@ static void __d_move(struct dentry * dentry, struct dentry * target) void d_move(struct dentry *dentry, struct dentry *target) { write_seqlock(&rename_lock); - __d_move(dentry, target); + __d_move(dentry, target, false); write_sequnlock(&rename_lock); } EXPORT_SYMBOL(d_move); +/* + * d_exchange - exchange two dentries + * @dentry1: first dentry + * @dentry2: second dentry + */ +void d_exchange(struct dentry *dentry1, struct dentry *dentry2) +{ + write_seqlock(&rename_lock); + + WARN_ON(!dentry1->d_inode); + WARN_ON(!dentry2->d_inode); + WARN_ON(IS_ROOT(dentry1)); + WARN_ON(IS_ROOT(dentry2)); + + __d_move(dentry1, dentry2, true); + + write_sequnlock(&rename_lock); +} + /** * d_ancestor - search for an ancestor * @p1: ancestor dentry @@ -2670,7 +2702,7 @@ static struct dentry *__d_unalias(struct inode *inode, m2 = &alias->d_parent->d_inode->i_mutex; out_unalias: if (likely(!d_mountpoint(alias))) { - __d_move(alias, dentry); + __d_move(alias, dentry, false); ret = alias; } out_err: diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index b167ca48b8ee..d4a9431ec73c 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -641,7 +641,7 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry, } rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry, lower_new_dir_dentry->d_inode, lower_new_dentry, - NULL); + NULL, 0); if (rc) goto out_lock; if (target_inode) diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index d050e043e884..1cb84f78909e 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -3000,6 +3000,154 @@ static struct buffer_head *ext4_get_first_dir_block(handle_t *handle, return ext4_get_first_inline_block(inode, parent_de, retval); } +struct ext4_renament { + struct inode *dir; + struct dentry *dentry; + struct inode *inode; + bool is_dir; + int dir_nlink_delta; + + /* entry for "dentry" */ + struct buffer_head *bh; + struct ext4_dir_entry_2 *de; + int inlined; + + /* entry for ".." in inode if it's a directory */ + struct buffer_head *dir_bh; + struct ext4_dir_entry_2 *parent_de; + int dir_inlined; +}; + +static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent) +{ + int retval; + + ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode, + &retval, &ent->parent_de, + &ent->dir_inlined); + if (!ent->dir_bh) + return retval; + if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino) + return -EIO; + BUFFER_TRACE(ent->dir_bh, "get_write_access"); + return ext4_journal_get_write_access(handle, ent->dir_bh); +} + +static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent, + unsigned dir_ino) +{ + int retval; + + ent->parent_de->inode = cpu_to_le32(dir_ino); + BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata"); + if (!ent->dir_inlined) { + if (is_dx(ent->inode)) { + retval = ext4_handle_dirty_dx_node(handle, + ent->inode, + ent->dir_bh); + } else { + retval = ext4_handle_dirty_dirent_node(handle, + ent->inode, + ent->dir_bh); + } + } else { + retval = ext4_mark_inode_dirty(handle, ent->inode); + } + if (retval) { + ext4_std_error(ent->dir->i_sb, retval); + return retval; + } + return 0; +} + +static int ext4_setent(handle_t *handle, struct ext4_renament *ent, + unsigned ino, unsigned file_type) +{ + int retval; + + BUFFER_TRACE(ent->bh, "get write access"); + retval = ext4_journal_get_write_access(handle, ent->bh); + if (retval) + return retval; + ent->de->inode = cpu_to_le32(ino); + if (EXT4_HAS_INCOMPAT_FEATURE(ent->dir->i_sb, + EXT4_FEATURE_INCOMPAT_FILETYPE)) + ent->de->file_type = file_type; + ent->dir->i_version++; + ent->dir->i_ctime = ent->dir->i_mtime = + ext4_current_time(ent->dir); + ext4_mark_inode_dirty(handle, ent->dir); + BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata"); + if (!ent->inlined) { + retval = ext4_handle_dirty_dirent_node(handle, + ent->dir, ent->bh); + if (unlikely(retval)) { + ext4_std_error(ent->dir->i_sb, retval); + return retval; + } + } + brelse(ent->bh); + ent->bh = NULL; + + return 0; +} + +static int ext4_find_delete_entry(handle_t *handle, struct inode *dir, + const struct qstr *d_name) +{ + int retval = -ENOENT; + struct buffer_head *bh; + struct ext4_dir_entry_2 *de; + + bh = ext4_find_entry(dir, d_name, &de, NULL); + if (bh) { + retval = ext4_delete_entry(handle, dir, de, bh); + brelse(bh); + } + return retval; +} + +static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent) +{ + int retval; + /* + * ent->de could have moved from under us during htree split, so make + * sure that we are deleting the right entry. We might also be pointing + * to a stale entry in the unused part of ent->bh so just checking inum + * and the name isn't enough. + */ + if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino || + ent->de->name_len != ent->dentry->d_name.len || + strncmp(ent->de->name, ent->dentry->d_name.name, + ent->de->name_len)) { + retval = ext4_find_delete_entry(handle, ent->dir, + &ent->dentry->d_name); + } else { + retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh); + if (retval == -ENOENT) { + retval = ext4_find_delete_entry(handle, ent->dir, + &ent->dentry->d_name); + } + } + + if (retval) { + ext4_warning(ent->dir->i_sb, + "Deleting old file (%lu), %d, error=%d", + ent->dir->i_ino, ent->dir->i_nlink, retval); + } +} + +static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent) +{ + if (ent->dir_nlink_delta) { + if (ent->dir_nlink_delta == -1) + ext4_dec_count(handle, ent->dir); + else + ext4_inc_count(handle, ent->dir); + ext4_mark_inode_dirty(handle, ent->dir); + } +} + /* * Anybody can rename anything with this: the permission checks are left to the * higher-level routines. @@ -3012,198 +3160,267 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry) { handle_t *handle = NULL; - struct inode *old_inode, *new_inode; - struct buffer_head *old_bh, *new_bh, *dir_bh; - struct ext4_dir_entry_2 *old_de, *new_de; + struct ext4_renament old = { + .dir = old_dir, + .dentry = old_dentry, + .inode = old_dentry->d_inode, + }; + struct ext4_renament new = { + .dir = new_dir, + .dentry = new_dentry, + .inode = new_dentry->d_inode, + }; int retval; - int inlined = 0, new_inlined = 0; - struct ext4_dir_entry_2 *parent_de; - dquot_initialize(old_dir); - dquot_initialize(new_dir); - - old_bh = new_bh = dir_bh = NULL; + dquot_initialize(old.dir); + dquot_initialize(new.dir); /* Initialize quotas before so that eventual writes go * in separate transaction */ - if (new_dentry->d_inode) - dquot_initialize(new_dentry->d_inode); + if (new.inode) + dquot_initialize(new.inode); - old_bh = ext4_find_entry(old_dir, &old_dentry->d_name, &old_de, NULL); + old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL); /* * Check for inode number is _not_ due to possible IO errors. * We might rmdir the source, keep it as pwd of some process * and merrily kill the link to whatever was created under the * same name. Goodbye sticky bit ;-< */ - old_inode = old_dentry->d_inode; retval = -ENOENT; - if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino) + if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) goto end_rename; - new_inode = new_dentry->d_inode; - new_bh = ext4_find_entry(new_dir, &new_dentry->d_name, - &new_de, &new_inlined); - if (new_bh) { - if (!new_inode) { - brelse(new_bh); - new_bh = NULL; + new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, + &new.de, &new.inlined); + if (new.bh) { + if (!new.inode) { + brelse(new.bh); + new.bh = NULL; } } - if (new_inode && !test_opt(new_dir->i_sb, NO_AUTO_DA_ALLOC)) - ext4_alloc_da_blocks(old_inode); + if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC)) + ext4_alloc_da_blocks(old.inode); - handle = ext4_journal_start(old_dir, EXT4_HT_DIR, - (2 * EXT4_DATA_TRANS_BLOCKS(old_dir->i_sb) + + handle = ext4_journal_start(old.dir, EXT4_HT_DIR, + (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2)); if (IS_ERR(handle)) return PTR_ERR(handle); - if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir)) + if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) ext4_handle_sync(handle); - if (S_ISDIR(old_inode->i_mode)) { - if (new_inode) { + if (S_ISDIR(old.inode->i_mode)) { + if (new.inode) { retval = -ENOTEMPTY; - if (!empty_dir(new_inode)) + if (!empty_dir(new.inode)) + goto end_rename; + } else { + retval = -EMLINK; + if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir)) goto end_rename; } - retval = -EIO; - dir_bh = ext4_get_first_dir_block(handle, old_inode, - &retval, &parent_de, - &inlined); - if (!dir_bh) - goto end_rename; - if (le32_to_cpu(parent_de->inode) != old_dir->i_ino) - goto end_rename; - retval = -EMLINK; - if (!new_inode && new_dir != old_dir && - EXT4_DIR_LINK_MAX(new_dir)) - goto end_rename; - BUFFER_TRACE(dir_bh, "get_write_access"); - retval = ext4_journal_get_write_access(handle, dir_bh); + retval = ext4_rename_dir_prepare(handle, &old); if (retval) goto end_rename; } - if (!new_bh) { - retval = ext4_add_entry(handle, new_dentry, old_inode); + if (!new.bh) { + retval = ext4_add_entry(handle, new.dentry, old.inode); if (retval) goto end_rename; } else { - BUFFER_TRACE(new_bh, "get write access"); - retval = ext4_journal_get_write_access(handle, new_bh); + retval = ext4_setent(handle, &new, + old.inode->i_ino, old.de->file_type); if (retval) goto end_rename; - new_de->inode = cpu_to_le32(old_inode->i_ino); - if (EXT4_HAS_INCOMPAT_FEATURE(new_dir->i_sb, - EXT4_FEATURE_INCOMPAT_FILETYPE)) - new_de->file_type = old_de->file_type; - new_dir->i_version++; - new_dir->i_ctime = new_dir->i_mtime = - ext4_current_time(new_dir); - ext4_mark_inode_dirty(handle, new_dir); - BUFFER_TRACE(new_bh, "call ext4_handle_dirty_metadata"); - if (!new_inlined) { - retval = ext4_handle_dirty_dirent_node(handle, - new_dir, new_bh); - if (unlikely(retval)) { - ext4_std_error(new_dir->i_sb, retval); - goto end_rename; - } - } - brelse(new_bh); - new_bh = NULL; } /* * Like most other Unix systems, set the ctime for inodes on a * rename. */ - old_inode->i_ctime = ext4_current_time(old_inode); - ext4_mark_inode_dirty(handle, old_inode); + old.inode->i_ctime = ext4_current_time(old.inode); + ext4_mark_inode_dirty(handle, old.inode); /* * ok, that's it */ - if (le32_to_cpu(old_de->inode) != old_inode->i_ino || - old_de->name_len != old_dentry->d_name.len || - strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) || - (retval = ext4_delete_entry(handle, old_dir, - old_de, old_bh)) == -ENOENT) { - /* old_de could have moved from under us during htree split, so - * make sure that we are deleting the right entry. We might - * also be pointing to a stale entry in the unused part of - * old_bh so just checking inum and the name isn't enough. */ - struct buffer_head *old_bh2; - struct ext4_dir_entry_2 *old_de2; - - old_bh2 = ext4_find_entry(old_dir, &old_dentry->d_name, - &old_de2, NULL); - if (old_bh2) { - retval = ext4_delete_entry(handle, old_dir, - old_de2, old_bh2); - brelse(old_bh2); - } + ext4_rename_delete(handle, &old); + + if (new.inode) { + ext4_dec_count(handle, new.inode); + new.inode->i_ctime = ext4_current_time(new.inode); } - if (retval) { - ext4_warning(old_dir->i_sb, - "Deleting old file (%lu), %d, error=%d", - old_dir->i_ino, old_dir->i_nlink, retval); - } - - if (new_inode) { - ext4_dec_count(handle, new_inode); - new_inode->i_ctime = ext4_current_time(new_inode); - } - old_dir->i_ctime = old_dir->i_mtime = ext4_current_time(old_dir); - ext4_update_dx_flag(old_dir); - if (dir_bh) { - parent_de->inode = cpu_to_le32(new_dir->i_ino); - BUFFER_TRACE(dir_bh, "call ext4_handle_dirty_metadata"); - if (!inlined) { - if (is_dx(old_inode)) { - retval = ext4_handle_dirty_dx_node(handle, - old_inode, - dir_bh); - } else { - retval = ext4_handle_dirty_dirent_node(handle, - old_inode, dir_bh); - } - } else { - retval = ext4_mark_inode_dirty(handle, old_inode); - } - if (retval) { - ext4_std_error(old_dir->i_sb, retval); + old.dir->i_ctime = old.dir->i_mtime = ext4_current_time(old.dir); + ext4_update_dx_flag(old.dir); + if (old.dir_bh) { + retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); + if (retval) goto end_rename; - } - ext4_dec_count(handle, old_dir); - if (new_inode) { + + ext4_dec_count(handle, old.dir); + if (new.inode) { /* checked empty_dir above, can't have another parent, * ext4_dec_count() won't work for many-linked dirs */ - clear_nlink(new_inode); + clear_nlink(new.inode); } else { - ext4_inc_count(handle, new_dir); - ext4_update_dx_flag(new_dir); - ext4_mark_inode_dirty(handle, new_dir); + ext4_inc_count(handle, new.dir); + ext4_update_dx_flag(new.dir); + ext4_mark_inode_dirty(handle, new.dir); } } - ext4_mark_inode_dirty(handle, old_dir); - if (new_inode) { - ext4_mark_inode_dirty(handle, new_inode); - if (!new_inode->i_nlink) - ext4_orphan_add(handle, new_inode); + ext4_mark_inode_dirty(handle, old.dir); + if (new.inode) { + ext4_mark_inode_dirty(handle, new.inode); + if (!new.inode->i_nlink) + ext4_orphan_add(handle, new.inode); } retval = 0; end_rename: - brelse(dir_bh); - brelse(old_bh); - brelse(new_bh); + brelse(old.dir_bh); + brelse(old.bh); + brelse(new.bh); if (handle) ext4_journal_stop(handle); return retval; } +static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry) +{ + handle_t *handle = NULL; + struct ext4_renament old = { + .dir = old_dir, + .dentry = old_dentry, + .inode = old_dentry->d_inode, + }; + struct ext4_renament new = { + .dir = new_dir, + .dentry = new_dentry, + .inode = new_dentry->d_inode, + }; + u8 new_file_type; + int retval; + + dquot_initialize(old.dir); + dquot_initialize(new.dir); + + old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, + &old.de, &old.inlined); + /* + * Check for inode number is _not_ due to possible IO errors. + * We might rmdir the source, keep it as pwd of some process + * and merrily kill the link to whatever was created under the + * same name. Goodbye sticky bit ;-< + */ + retval = -ENOENT; + if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) + goto end_rename; + + new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, + &new.de, &new.inlined); + + /* RENAME_EXCHANGE case: old *and* new must both exist */ + if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino) + goto end_rename; + + handle = ext4_journal_start(old.dir, EXT4_HT_DIR, + (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + + 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2)); + if (IS_ERR(handle)) + return PTR_ERR(handle); + + if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) + ext4_handle_sync(handle); + + if (S_ISDIR(old.inode->i_mode)) { + old.is_dir = true; + retval = ext4_rename_dir_prepare(handle, &old); + if (retval) + goto end_rename; + } + if (S_ISDIR(new.inode->i_mode)) { + new.is_dir = true; + retval = ext4_rename_dir_prepare(handle, &new); + if (retval) + goto end_rename; + } + + /* + * Other than the special case of overwriting a directory, parents' + * nlink only needs to be modified if this is a cross directory rename. + */ + if (old.dir != new.dir && old.is_dir != new.is_dir) { + old.dir_nlink_delta = old.is_dir ? -1 : 1; + new.dir_nlink_delta = -old.dir_nlink_delta; + retval = -EMLINK; + if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) || + (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir))) + goto end_rename; + } + + new_file_type = new.de->file_type; + retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type); + if (retval) + goto end_rename; + + retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type); + if (retval) + goto end_rename; + + /* + * Like most other Unix systems, set the ctime for inodes on a + * rename. + */ + old.inode->i_ctime = ext4_current_time(old.inode); + new.inode->i_ctime = ext4_current_time(new.inode); + ext4_mark_inode_dirty(handle, old.inode); + ext4_mark_inode_dirty(handle, new.inode); + + if (old.dir_bh) { + retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); + if (retval) + goto end_rename; + } + if (new.dir_bh) { + retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino); + if (retval) + goto end_rename; + } + ext4_update_dir_count(handle, &old); + ext4_update_dir_count(handle, &new); + retval = 0; + +end_rename: + brelse(old.dir_bh); + brelse(new.dir_bh); + brelse(old.bh); + brelse(new.bh); + if (handle) + ext4_journal_stop(handle); + return retval; +} + +static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry, + unsigned int flags) +{ + if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE)) + return -EINVAL; + + if (flags & RENAME_EXCHANGE) { + return ext4_cross_rename(old_dir, old_dentry, + new_dir, new_dentry); + } + /* + * Existence checking was done by the VFS, otherwise "RENAME_NOREPLACE" + * is equivalent to regular rename. + */ + return ext4_rename(old_dir, old_dentry, new_dir, new_dentry); +} + /* * directories can handle most operations... */ @@ -3218,6 +3435,7 @@ const struct inode_operations ext4_dir_inode_operations = { .mknod = ext4_mknod, .tmpfile = ext4_tmpfile, .rename = ext4_rename, + .rename2 = ext4_rename2, .setattr = ext4_setattr, .setxattr = generic_setxattr, .getxattr = generic_getxattr, diff --git a/fs/inode.c b/fs/inode.c index e6905152c39f..fb59ba7967f1 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -944,24 +944,22 @@ EXPORT_SYMBOL(unlock_new_inode); /** * lock_two_nondirectories - take two i_mutexes on non-directory objects + * + * Lock any non-NULL argument that is not a directory. + * Zero, one or two objects may be locked by this function. + * * @inode1: first inode to lock * @inode2: second inode to lock */ void lock_two_nondirectories(struct inode *inode1, struct inode *inode2) { - WARN_ON_ONCE(S_ISDIR(inode1->i_mode)); - if (inode1 == inode2 || !inode2) { - mutex_lock(&inode1->i_mutex); - return; - } - WARN_ON_ONCE(S_ISDIR(inode2->i_mode)); - if (inode1 < inode2) { + if (inode1 > inode2) + swap(inode1, inode2); + + if (inode1 && !S_ISDIR(inode1->i_mode)) mutex_lock(&inode1->i_mutex); + if (inode2 && !S_ISDIR(inode2->i_mode) && inode2 != inode1) mutex_lock_nested(&inode2->i_mutex, I_MUTEX_NONDIR2); - } else { - mutex_lock(&inode2->i_mutex); - mutex_lock_nested(&inode1->i_mutex, I_MUTEX_NONDIR2); - } } EXPORT_SYMBOL(lock_two_nondirectories); @@ -972,8 +970,9 @@ EXPORT_SYMBOL(lock_two_nondirectories); */ void unlock_two_nondirectories(struct inode *inode1, struct inode *inode2) { - mutex_unlock(&inode1->i_mutex); - if (inode2 && inode2 != inode1) + if (inode1 && !S_ISDIR(inode1->i_mode)) + mutex_unlock(&inode1->i_mutex); + if (inode2 && !S_ISDIR(inode2->i_mode) && inode2 != inode1) mutex_unlock(&inode2->i_mutex); } EXPORT_SYMBOL(unlock_two_nondirectories); diff --git a/fs/namei.c b/fs/namei.c index 4b491b431990..c1178880f23c 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1796,7 +1796,7 @@ static int link_path_walk(const char *name, struct nameidata *nd) if (err) return err; } - if (!d_is_directory(nd->path.dentry)) { + if (!d_can_lookup(nd->path.dentry)) { err = -ENOTDIR; break; } @@ -1817,7 +1817,7 @@ static int path_init(int dfd, const char *name, unsigned int flags, struct dentry *root = nd->root.dentry; struct inode *inode = root->d_inode; if (*name) { - if (!d_is_directory(root)) + if (!d_can_lookup(root)) return -ENOTDIR; retval = inode_permission(inode, MAY_EXEC); if (retval) @@ -1873,7 +1873,7 @@ static int path_init(int dfd, const char *name, unsigned int flags, dentry = f.file->f_path.dentry; if (*name) { - if (!d_is_directory(dentry)) { + if (!d_can_lookup(dentry)) { fdput(f); return -ENOTDIR; } @@ -1955,7 +1955,7 @@ static int path_lookupat(int dfd, const char *name, err = complete_walk(nd); if (!err && nd->flags & LOOKUP_DIRECTORY) { - if (!d_is_directory(nd->path.dentry)) { + if (!d_can_lookup(nd->path.dentry)) { path_put(&nd->path); err = -ENOTDIR; } @@ -2414,11 +2414,11 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir) IS_IMMUTABLE(inode) || IS_SWAPFILE(inode)) return -EPERM; if (isdir) { - if (!d_is_directory(victim) && !d_is_autodir(victim)) + if (!d_is_dir(victim)) return -ENOTDIR; if (IS_ROOT(victim)) return -EBUSY; - } else if (d_is_directory(victim) || d_is_autodir(victim)) + } else if (d_is_dir(victim)) return -EISDIR; if (IS_DEADDIR(dir)) return -ENOENT; @@ -3016,11 +3016,10 @@ finish_open: } audit_inode(name, nd->path.dentry, 0); error = -EISDIR; - if ((open_flag & O_CREAT) && - (d_is_directory(nd->path.dentry) || d_is_autodir(nd->path.dentry))) + if ((open_flag & O_CREAT) && d_is_dir(nd->path.dentry)) goto out; error = -ENOTDIR; - if ((nd->flags & LOOKUP_DIRECTORY) && !d_is_directory(nd->path.dentry)) + if ((nd->flags & LOOKUP_DIRECTORY) && !d_can_lookup(nd->path.dentry)) goto out; if (!S_ISREG(nd->inode->i_mode)) will_truncate = false; @@ -3744,7 +3743,7 @@ exit1: slashes: if (d_is_negative(dentry)) error = -ENOENT; - else if (d_is_directory(dentry) || d_is_autodir(dentry)) + else if (d_is_dir(dentry)) error = -EISDIR; else error = -ENOTDIR; @@ -3974,7 +3973,28 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname return sys_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0); } -/* +/** + * vfs_rename - rename a filesystem object + * @old_dir: parent of source + * @old_dentry: source + * @new_dir: parent of destination + * @new_dentry: destination + * @delegated_inode: returns an inode needing a delegation break + * @flags: rename flags + * + * The caller must hold multiple mutexes--see lock_rename()). + * + * If vfs_rename discovers a delegation in need of breaking at either + * the source or destination, it will return -EWOULDBLOCK and return a + * reference to the inode in delegated_inode. The caller should then + * break the delegation and retry. Because breaking a delegation may + * take a long time, the caller should drop all locks before doing + * so. + * + * Alternatively, a caller may pass NULL for delegated_inode. This may + * be appropriate for callers that expect the underlying filesystem not + * to be NFS exported. + * * The worst of all namespace operations - renaming directory. "Perverted" * doesn't even start to describe it. Somebody in UCB had a heck of a trip... * Problems: @@ -4002,163 +4022,139 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname * ->i_mutex on parents, which works but leads to some truly excessive * locking]. */ -static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry, - struct inode *new_dir, struct dentry *new_dentry) +int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry, + struct inode **delegated_inode, unsigned int flags) { - int error = 0; + int error; + bool is_dir = d_is_dir(old_dentry); + const unsigned char *old_name; + struct inode *source = old_dentry->d_inode; struct inode *target = new_dentry->d_inode; + bool new_is_dir = false; unsigned max_links = new_dir->i_sb->s_max_links; + if (source == target) + return 0; + + error = may_delete(old_dir, old_dentry, is_dir); + if (error) + return error; + + if (!target) { + error = may_create(new_dir, new_dentry); + } else { + new_is_dir = d_is_dir(new_dentry); + + if (!(flags & RENAME_EXCHANGE)) + error = may_delete(new_dir, new_dentry, is_dir); + else + error = may_delete(new_dir, new_dentry, new_is_dir); + } + if (error) + return error; + + if (!old_dir->i_op->rename) + return -EPERM; + + if (flags && !old_dir->i_op->rename2) + return -EINVAL; + /* * If we are going to change the parent - check write permissions, * we'll need to flip '..'. */ if (new_dir != old_dir) { - error = inode_permission(old_dentry->d_inode, MAY_WRITE); - if (error) - return error; + if (is_dir) { + error = inode_permission(source, MAY_WRITE); + if (error) + return error; + } + if ((flags & RENAME_EXCHANGE) && new_is_dir) { + error = inode_permission(target, MAY_WRITE); + if (error) + return error; + } } - error = security_inode_rename(old_dir, old_dentry, new_dir, new_dentry); + error = security_inode_rename(old_dir, old_dentry, new_dir, new_dentry, + flags); if (error) return error; + old_name = fsnotify_oldname_init(old_dentry->d_name.name); dget(new_dentry); - if (target) + if (!is_dir || (flags & RENAME_EXCHANGE)) + lock_two_nondirectories(source, target); + else if (target) mutex_lock(&target->i_mutex); error = -EBUSY; if (d_mountpoint(old_dentry) || d_mountpoint(new_dentry)) goto out; - error = -EMLINK; - if (max_links && !target && new_dir != old_dir && - new_dir->i_nlink >= max_links) - goto out; - - if (target) + if (max_links && new_dir != old_dir) { + error = -EMLINK; + if (is_dir && !new_is_dir && new_dir->i_nlink >= max_links) + goto out; + if ((flags & RENAME_EXCHANGE) && !is_dir && new_is_dir && + old_dir->i_nlink >= max_links) + goto out; + } + if (is_dir && !(flags & RENAME_EXCHANGE) && target) shrink_dcache_parent(new_dentry); - error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry); - if (error) - goto out; - - if (target) { - target->i_flags |= S_DEAD; - dont_mount(new_dentry); + if (!is_dir) { + error = try_break_deleg(source, delegated_inode); + if (error) + goto out; } -out: - if (target) - mutex_unlock(&target->i_mutex); - dput(new_dentry); - if (!error) - if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE)) - d_move(old_dentry,new_dentry); - return error; -} - -static int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry, - struct inode *new_dir, struct dentry *new_dentry, - struct inode **delegated_inode) -{ - struct inode *target = new_dentry->d_inode; - struct inode *source = old_dentry->d_inode; - int error; - - error = security_inode_rename(old_dir, old_dentry, new_dir, new_dentry); - if (error) - return error; - - dget(new_dentry); - lock_two_nondirectories(source, target); - - error = -EBUSY; - if (d_mountpoint(old_dentry)||d_mountpoint(new_dentry)) - goto out; - - error = try_break_deleg(source, delegated_inode); - if (error) - goto out; - if (target) { + if (target && !new_is_dir) { error = try_break_deleg(target, delegated_inode); if (error) goto out; } - error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry); + if (!flags) { + error = old_dir->i_op->rename(old_dir, old_dentry, + new_dir, new_dentry); + } else { + error = old_dir->i_op->rename2(old_dir, old_dentry, + new_dir, new_dentry, flags); + } if (error) goto out; - if (target) + if (!(flags & RENAME_EXCHANGE) && target) { + if (is_dir) + target->i_flags |= S_DEAD; dont_mount(new_dentry); - if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE)) - d_move(old_dentry, new_dentry); + } + if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE)) { + if (!(flags & RENAME_EXCHANGE)) + d_move(old_dentry, new_dentry); + else + d_exchange(old_dentry, new_dentry); + } out: - unlock_two_nondirectories(source, target); + if (!is_dir || (flags & RENAME_EXCHANGE)) + unlock_two_nondirectories(source, target); + else if (target) + mutex_unlock(&target->i_mutex); dput(new_dentry); - return error; -} - -/** - * vfs_rename - rename a filesystem object - * @old_dir: parent of source - * @old_dentry: source - * @new_dir: parent of destination - * @new_dentry: destination - * @delegated_inode: returns an inode needing a delegation break - * - * The caller must hold multiple mutexes--see lock_rename()). - * - * If vfs_rename discovers a delegation in need of breaking at either - * the source or destination, it will return -EWOULDBLOCK and return a - * reference to the inode in delegated_inode. The caller should then - * break the delegation and retry. Because breaking a delegation may - * take a long time, the caller should drop all locks before doing - * so. - * - * Alternatively, a caller may pass NULL for delegated_inode. This may - * be appropriate for callers that expect the underlying filesystem not - * to be NFS exported. - */ -int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, - struct inode *new_dir, struct dentry *new_dentry, - struct inode **delegated_inode) -{ - int error; - int is_dir = d_is_directory(old_dentry) || d_is_autodir(old_dentry); - const unsigned char *old_name; - - if (old_dentry->d_inode == new_dentry->d_inode) - return 0; - - error = may_delete(old_dir, old_dentry, is_dir); - if (error) - return error; - - if (!new_dentry->d_inode) - error = may_create(new_dir, new_dentry); - else - error = may_delete(new_dir, new_dentry, is_dir); - if (error) - return error; - - if (!old_dir->i_op->rename) - return -EPERM; - - old_name = fsnotify_oldname_init(old_dentry->d_name.name); - - if (is_dir) - error = vfs_rename_dir(old_dir,old_dentry,new_dir,new_dentry); - else - error = vfs_rename_other(old_dir,old_dentry,new_dir,new_dentry,delegated_inode); - if (!error) + if (!error) { fsnotify_move(old_dir, new_dir, old_name, is_dir, - new_dentry->d_inode, old_dentry); + !(flags & RENAME_EXCHANGE) ? target : NULL, old_dentry); + if (flags & RENAME_EXCHANGE) { + fsnotify_move(new_dir, old_dir, old_dentry->d_name.name, + new_is_dir, NULL, new_dentry); + } + } fsnotify_oldname_free(old_name); return error; } -SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname, - int, newdfd, const char __user *, newname) +SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname, + int, newdfd, const char __user *, newname, unsigned int, flags) { struct dentry *old_dir, *new_dir; struct dentry *old_dentry, *new_dentry; @@ -4170,6 +4166,13 @@ SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname, unsigned int lookup_flags = 0; bool should_retry = false; int error; + + if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE)) + return -EINVAL; + + if ((flags & RENAME_NOREPLACE) && (flags & RENAME_EXCHANGE)) + return -EINVAL; + retry: from = user_path_parent(olddfd, oldname, &oldnd, lookup_flags); if (IS_ERR(from)) { @@ -4193,6 +4196,8 @@ retry: goto exit2; new_dir = newnd.path.dentry; + if (flags & RENAME_NOREPLACE) + error = -EEXIST; if (newnd.last_type != LAST_NORM) goto exit2; @@ -4202,7 +4207,8 @@ retry: oldnd.flags &= ~LOOKUP_PARENT; newnd.flags &= ~LOOKUP_PARENT; - newnd.flags |= LOOKUP_RENAME_TARGET; + if (!(flags & RENAME_EXCHANGE)) + newnd.flags |= LOOKUP_RENAME_TARGET; retry_deleg: trap = lock_rename(new_dir, old_dir); @@ -4215,34 +4221,49 @@ retry_deleg: error = -ENOENT; if (d_is_negative(old_dentry)) goto exit4; + new_dentry = lookup_hash(&newnd); + error = PTR_ERR(new_dentry); + if (IS_ERR(new_dentry)) + goto exit4; + error = -EEXIST; + if ((flags & RENAME_NOREPLACE) && d_is_positive(new_dentry)) + goto exit5; + if (flags & RENAME_EXCHANGE) { + error = -ENOENT; + if (d_is_negative(new_dentry)) + goto exit5; + + if (!d_is_dir(new_dentry)) { + error = -ENOTDIR; + if (newnd.last.name[newnd.last.len]) + goto exit5; + } + } /* unless the source is a directory trailing slashes give -ENOTDIR */ - if (!d_is_directory(old_dentry) && !d_is_autodir(old_dentry)) { + if (!d_is_dir(old_dentry)) { error = -ENOTDIR; if (oldnd.last.name[oldnd.last.len]) - goto exit4; - if (newnd.last.name[newnd.last.len]) - goto exit4; + goto exit5; + if (!(flags & RENAME_EXCHANGE) && newnd.last.name[newnd.last.len]) + goto exit5; } /* source should not be ancestor of target */ error = -EINVAL; if (old_dentry == trap) - goto exit4; - new_dentry = lookup_hash(&newnd); - error = PTR_ERR(new_dentry); - if (IS_ERR(new_dentry)) - goto exit4; + goto exit5; /* target should not be an ancestor of source */ - error = -ENOTEMPTY; + if (!(flags & RENAME_EXCHANGE)) + error = -ENOTEMPTY; if (new_dentry == trap) goto exit5; error = security_path_rename(&oldnd.path, old_dentry, - &newnd.path, new_dentry); + &newnd.path, new_dentry, flags); if (error) goto exit5; error = vfs_rename(old_dir->d_inode, old_dentry, - new_dir->d_inode, new_dentry, - &delegated_inode); + new_dir->d_inode, new_dentry, + &delegated_inode, flags); exit5: dput(new_dentry); exit4: @@ -4272,9 +4293,15 @@ exit: return error; } +SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname, + int, newdfd, const char __user *, newname) +{ + return sys_renameat2(olddfd, oldname, newdfd, newname, 0); +} + SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newname) { - return sys_renameat(AT_FDCWD, oldname, AT_FDCWD, newname); + return sys_renameat2(AT_FDCWD, oldname, AT_FDCWD, newname, 0); } int vfs_readlink(struct dentry *dentry, char __user *buffer, int buflen, const char *link) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 6d7be3f80356..915808b36df7 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1694,7 +1694,7 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, if (ffhp->fh_export->ex_path.dentry != tfhp->fh_export->ex_path.dentry) goto out_dput_new; - host_err = vfs_rename(fdir, odentry, tdir, ndentry, NULL); + host_err = vfs_rename(fdir, odentry, tdir, ndentry, NULL, 0); if (!host_err) { host_err = commit_metadata(tfhp); if (!host_err) diff --git a/include/linux/dcache.h b/include/linux/dcache.h index bf72e9ac6de0..3b9bfdb83ba6 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -308,6 +308,7 @@ extern void dentry_update_name_case(struct dentry *, struct qstr *); /* used for rename() and baskets */ extern void d_move(struct dentry *, struct dentry *); +extern void d_exchange(struct dentry *, struct dentry *); extern struct dentry *d_ancestor(struct dentry *, struct dentry *); /* appendix may either be NULL or be used for transname suffixes */ @@ -429,7 +430,7 @@ static inline unsigned __d_entry_type(const struct dentry *dentry) return dentry->d_flags & DCACHE_ENTRY_TYPE; } -static inline bool d_is_directory(const struct dentry *dentry) +static inline bool d_can_lookup(const struct dentry *dentry) { return __d_entry_type(dentry) == DCACHE_DIRECTORY_TYPE; } @@ -439,6 +440,11 @@ static inline bool d_is_autodir(const struct dentry *dentry) return __d_entry_type(dentry) == DCACHE_AUTODIR_TYPE; } +static inline bool d_is_dir(const struct dentry *dentry) +{ + return d_can_lookup(dentry) || d_is_autodir(dentry); +} + static inline bool d_is_symlink(const struct dentry *dentry) { return __d_entry_type(dentry) == DCACHE_SYMLINK_TYPE; diff --git a/include/linux/fs.h b/include/linux/fs.h index 3ca9420f627e..215cb1b09f47 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1461,7 +1461,7 @@ extern int vfs_symlink(struct inode *, struct dentry *, const char *); extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **); extern int vfs_rmdir(struct inode *, struct dentry *); extern int vfs_unlink(struct inode *, struct dentry *, struct inode **); -extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **); +extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **, unsigned int); /* * VFS dentry helper functions. @@ -1572,6 +1572,8 @@ struct inode_operations { int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t); int (*rename) (struct inode *, struct dentry *, struct inode *, struct dentry *); + int (*rename2) (struct inode *, struct dentry *, + struct inode *, struct dentry *, unsigned int); int (*setattr) (struct dentry *, struct iattr *); int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *); int (*setxattr) (struct dentry *, const char *,const void *,size_t,int); diff --git a/include/linux/security.h b/include/linux/security.h index 2fc42d191f79..6478ce3252c7 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -1793,7 +1793,8 @@ int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) int security_inode_rmdir(struct inode *dir, struct dentry *dentry); int security_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev); int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry, - struct inode *new_dir, struct dentry *new_dentry); + struct inode *new_dir, struct dentry *new_dentry, + unsigned int flags); int security_inode_readlink(struct dentry *dentry); int security_inode_follow_link(struct dentry *dentry, struct nameidata *nd); int security_inode_permission(struct inode *inode, int mask); @@ -2161,7 +2162,8 @@ static inline int security_inode_mknod(struct inode *dir, static inline int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, - struct dentry *new_dentry) + struct dentry *new_dentry, + unsigned int flags) { return 0; } @@ -2955,7 +2957,8 @@ int security_path_symlink(struct path *dir, struct dentry *dentry, int security_path_link(struct dentry *old_dentry, struct path *new_dir, struct dentry *new_dentry); int security_path_rename(struct path *old_dir, struct dentry *old_dentry, - struct path *new_dir, struct dentry *new_dentry); + struct path *new_dir, struct dentry *new_dentry, + unsigned int flags); int security_path_chmod(struct path *path, umode_t mode); int security_path_chown(struct path *path, kuid_t uid, kgid_t gid); int security_path_chroot(struct path *path); @@ -3003,7 +3006,8 @@ static inline int security_path_link(struct dentry *old_dentry, static inline int security_path_rename(struct path *old_dir, struct dentry *old_dentry, struct path *new_dir, - struct dentry *new_dentry) + struct dentry *new_dentry, + unsigned int flags) { return 0; } diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h index 6c28b61bb690..ca1a11bb4443 100644 --- a/include/uapi/linux/fs.h +++ b/include/uapi/linux/fs.h @@ -35,6 +35,9 @@ #define SEEK_HOLE 4 /* seek to the next hole */ #define SEEK_MAX SEEK_HOLE +#define RENAME_NOREPLACE (1 << 0) /* Don't overwrite target */ +#define RENAME_EXCHANGE (1 << 1) /* Exchange source and dest */ + struct fstrim_range { __u64 start; __u64 len; diff --git a/security/security.c b/security/security.c index 919cad93ac82..8b774f362a3d 100644 --- a/security/security.c +++ b/security/security.c @@ -433,11 +433,20 @@ int security_path_link(struct dentry *old_dentry, struct path *new_dir, } int security_path_rename(struct path *old_dir, struct dentry *old_dentry, - struct path *new_dir, struct dentry *new_dentry) + struct path *new_dir, struct dentry *new_dentry, + unsigned int flags) { if (unlikely(IS_PRIVATE(old_dentry->d_inode) || (new_dentry->d_inode && IS_PRIVATE(new_dentry->d_inode)))) return 0; + + if (flags & RENAME_EXCHANGE) { + int err = security_ops->path_rename(new_dir, new_dentry, + old_dir, old_dentry); + if (err) + return err; + } + return security_ops->path_rename(old_dir, old_dentry, new_dir, new_dentry); } @@ -524,11 +533,20 @@ int security_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, } int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry, - struct inode *new_dir, struct dentry *new_dentry) + struct inode *new_dir, struct dentry *new_dentry, + unsigned int flags) { if (unlikely(IS_PRIVATE(old_dentry->d_inode) || (new_dentry->d_inode && IS_PRIVATE(new_dentry->d_inode)))) return 0; + + if (flags & RENAME_EXCHANGE) { + int err = security_ops->inode_rename(new_dir, new_dentry, + old_dir, old_dentry); + if (err) + return err; + } + return security_ops->inode_rename(old_dir, old_dentry, new_dir, new_dentry); } |