diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-11-22 14:15:27 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-11-22 14:15:27 -0800 |
commit | ecde00642c79c2dfc9006e7751ee60bd0e21e1e9 (patch) | |
tree | de4cca84e38a44c46a0d8f82b47aa96dba44c8e9 | |
parent | 8a84e01e147f44111988f9d8ccd2eaa30215a0f2 (diff) | |
parent | 3035b675ad0377b2468b442068062e7f28771dda (diff) |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
"Assorted fixes, most in overlayfs land"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ovl: ovl_dir_fsync() cleanup
ovl: update MAINTAINERS
ovl: pass dentry into ovl_dir_read_merged()
ovl: use lockless_dereference() for upperdentry
ovl: allow filenames with comma
ovl: fix race in private xattr checks
ovl: fix remove/copy-up race
ovl: rename filesystem type to "overlay"
isofs: avoid unused function warning
vfs: fix reference leak in d_prune_aliases()
-rw-r--r-- | Documentation/filesystems/overlayfs.txt | 2 | ||||
-rw-r--r-- | MAINTAINERS | 7 | ||||
-rw-r--r-- | fs/Makefile | 2 | ||||
-rw-r--r-- | fs/dcache.c | 1 | ||||
-rw-r--r-- | fs/isofs/inode.c | 42 | ||||
-rw-r--r-- | fs/overlayfs/Kconfig | 2 | ||||
-rw-r--r-- | fs/overlayfs/Makefile | 4 | ||||
-rw-r--r-- | fs/overlayfs/dir.c | 31 | ||||
-rw-r--r-- | fs/overlayfs/inode.c | 27 | ||||
-rw-r--r-- | fs/overlayfs/readdir.c | 39 | ||||
-rw-r--r-- | fs/overlayfs/super.c | 61 |
11 files changed, 133 insertions, 85 deletions
diff --git a/Documentation/filesystems/overlayfs.txt b/Documentation/filesystems/overlayfs.txt index 530850a72735..a27c950ece61 100644 --- a/Documentation/filesystems/overlayfs.txt +++ b/Documentation/filesystems/overlayfs.txt @@ -64,7 +64,7 @@ is formed. At mount time, the two directories given as mount options "lowerdir" and "upperdir" are combined into a merged directory: - mount -t overlayfs overlayfs -olowerdir=/lower,upperdir=/upper,\ + mount -t overlay overlay -olowerdir=/lower,upperdir=/upper,\ workdir=/work /merged The "workdir" needs to be an empty directory on the same filesystem diff --git a/MAINTAINERS b/MAINTAINERS index c444907ccd69..0ff630de8a6d 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -6888,11 +6888,12 @@ F: drivers/scsi/osd/ F: include/scsi/osd_* F: fs/exofs/ -OVERLAYFS FILESYSTEM +OVERLAY FILESYSTEM M: Miklos Szeredi <miklos@szeredi.hu> -L: linux-fsdevel@vger.kernel.org +L: linux-unionfs@vger.kernel.org +T: git git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs.git S: Supported -F: fs/overlayfs/* +F: fs/overlayfs/ F: Documentation/filesystems/overlayfs.txt P54 WIRELESS DRIVER diff --git a/fs/Makefile b/fs/Makefile index 34a1b9dea6dd..da0bbb456d3f 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -104,7 +104,7 @@ obj-$(CONFIG_QNX6FS_FS) += qnx6/ obj-$(CONFIG_AUTOFS4_FS) += autofs4/ obj-$(CONFIG_ADFS_FS) += adfs/ obj-$(CONFIG_FUSE_FS) += fuse/ -obj-$(CONFIG_OVERLAYFS_FS) += overlayfs/ +obj-$(CONFIG_OVERLAY_FS) += overlayfs/ obj-$(CONFIG_UDF_FS) += udf/ obj-$(CONFIG_SUN_OPENPROMFS) += openpromfs/ obj-$(CONFIG_OMFS_FS) += omfs/ diff --git a/fs/dcache.c b/fs/dcache.c index 3ffef7f4e5cd..5bc72b07fde2 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -778,6 +778,7 @@ restart: struct dentry *parent = lock_parent(dentry); if (likely(!dentry->d_lockref.count)) { __dentry_kill(dentry); + dput(parent); goto restart; } if (parent) diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c index fe839b915116..d67a16f2a45d 100644 --- a/fs/isofs/inode.c +++ b/fs/isofs/inode.c @@ -174,27 +174,6 @@ struct iso9660_options{ * Compute the hash for the isofs name corresponding to the dentry. */ static int -isofs_hash_common(struct qstr *qstr, int ms) -{ - const char *name; - int len; - - len = qstr->len; - name = qstr->name; - if (ms) { - while (len && name[len-1] == '.') - len--; - } - - qstr->hash = full_name_hash(name, len); - - return 0; -} - -/* - * Compute the hash for the isofs name corresponding to the dentry. - */ -static int isofs_hashi_common(struct qstr *qstr, int ms) { const char *name; @@ -263,6 +242,27 @@ isofs_dentry_cmpi(const struct dentry *parent, const struct dentry *dentry, } #ifdef CONFIG_JOLIET +/* + * Compute the hash for the isofs name corresponding to the dentry. + */ +static int +isofs_hash_common(struct qstr *qstr, int ms) +{ + const char *name; + int len; + + len = qstr->len; + name = qstr->name; + if (ms) { + while (len && name[len-1] == '.') + len--; + } + + qstr->hash = full_name_hash(name, len); + + return 0; +} + static int isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr) { diff --git a/fs/overlayfs/Kconfig b/fs/overlayfs/Kconfig index e60125976873..34355818a2e0 100644 --- a/fs/overlayfs/Kconfig +++ b/fs/overlayfs/Kconfig @@ -1,4 +1,4 @@ -config OVERLAYFS_FS +config OVERLAY_FS tristate "Overlay filesystem support" help An overlay filesystem combines two filesystems - an 'upper' filesystem diff --git a/fs/overlayfs/Makefile b/fs/overlayfs/Makefile index 8f91889480d0..900daed3e91d 100644 --- a/fs/overlayfs/Makefile +++ b/fs/overlayfs/Makefile @@ -2,6 +2,6 @@ # Makefile for the overlay filesystem. # -obj-$(CONFIG_OVERLAYFS_FS) += overlayfs.o +obj-$(CONFIG_OVERLAY_FS) += overlay.o -overlayfs-objs := super.o inode.o dir.o readdir.o copy_up.o +overlay-objs := super.o inode.o dir.o readdir.o copy_up.o diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index 15cd91ad9940..8ffc4b980f1b 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -284,8 +284,7 @@ out: return ERR_PTR(err); } -static struct dentry *ovl_check_empty_and_clear(struct dentry *dentry, - enum ovl_path_type type) +static struct dentry *ovl_check_empty_and_clear(struct dentry *dentry) { int err; struct dentry *ret = NULL; @@ -294,8 +293,17 @@ static struct dentry *ovl_check_empty_and_clear(struct dentry *dentry, err = ovl_check_empty_dir(dentry, &list); if (err) ret = ERR_PTR(err); - else if (type == OVL_PATH_MERGE) - ret = ovl_clear_empty(dentry, &list); + else { + /* + * If no upperdentry then skip clearing whiteouts. + * + * Can race with copy-up, since we don't hold the upperdir + * mutex. Doesn't matter, since copy-up can't create a + * non-empty directory from an empty one. + */ + if (ovl_dentry_upper(dentry)) + ret = ovl_clear_empty(dentry, &list); + } ovl_cache_free(&list); @@ -487,8 +495,7 @@ out: return err; } -static int ovl_remove_and_whiteout(struct dentry *dentry, - enum ovl_path_type type, bool is_dir) +static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir) { struct dentry *workdir = ovl_workdir(dentry); struct inode *wdir = workdir->d_inode; @@ -500,7 +507,7 @@ static int ovl_remove_and_whiteout(struct dentry *dentry, int err; if (is_dir) { - opaquedir = ovl_check_empty_and_clear(dentry, type); + opaquedir = ovl_check_empty_and_clear(dentry); err = PTR_ERR(opaquedir); if (IS_ERR(opaquedir)) goto out; @@ -515,9 +522,10 @@ static int ovl_remove_and_whiteout(struct dentry *dentry, if (IS_ERR(whiteout)) goto out_unlock; - if (type == OVL_PATH_LOWER) { + upper = ovl_dentry_upper(dentry); + if (!upper) { upper = lookup_one_len(dentry->d_name.name, upperdir, - dentry->d_name.len); + dentry->d_name.len); err = PTR_ERR(upper); if (IS_ERR(upper)) goto kill_whiteout; @@ -529,7 +537,6 @@ static int ovl_remove_and_whiteout(struct dentry *dentry, } else { int flags = 0; - upper = ovl_dentry_upper(dentry); if (opaquedir) upper = opaquedir; err = -ESTALE; @@ -648,7 +655,7 @@ static int ovl_do_remove(struct dentry *dentry, bool is_dir) cap_raise(override_cred->cap_effective, CAP_CHOWN); old_cred = override_creds(override_cred); - err = ovl_remove_and_whiteout(dentry, type, is_dir); + err = ovl_remove_and_whiteout(dentry, is_dir); revert_creds(old_cred); put_cred(override_cred); @@ -781,7 +788,7 @@ static int ovl_rename2(struct inode *olddir, struct dentry *old, } if (overwrite && (new_type == OVL_PATH_LOWER || new_type == OVL_PATH_MERGE) && new_is_dir) { - opaquedir = ovl_check_empty_and_clear(new, new_type); + opaquedir = ovl_check_empty_and_clear(new); err = PTR_ERR(opaquedir); if (IS_ERR(opaquedir)) { opaquedir = NULL; diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index af2d18c9fcee..07d74b24913b 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -235,26 +235,36 @@ out: return err; } +static bool ovl_need_xattr_filter(struct dentry *dentry, + enum ovl_path_type type) +{ + return type == OVL_PATH_UPPER && S_ISDIR(dentry->d_inode->i_mode); +} + ssize_t ovl_getxattr(struct dentry *dentry, const char *name, void *value, size_t size) { - if (ovl_path_type(dentry->d_parent) == OVL_PATH_MERGE && - ovl_is_private_xattr(name)) + struct path realpath; + enum ovl_path_type type = ovl_path_real(dentry, &realpath); + + if (ovl_need_xattr_filter(dentry, type) && ovl_is_private_xattr(name)) return -ENODATA; - return vfs_getxattr(ovl_dentry_real(dentry), name, value, size); + return vfs_getxattr(realpath.dentry, name, value, size); } ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size) { + struct path realpath; + enum ovl_path_type type = ovl_path_real(dentry, &realpath); ssize_t res; int off; - res = vfs_listxattr(ovl_dentry_real(dentry), list, size); + res = vfs_listxattr(realpath.dentry, list, size); if (res <= 0 || size == 0) return res; - if (ovl_path_type(dentry->d_parent) != OVL_PATH_MERGE) + if (!ovl_need_xattr_filter(dentry, type)) return res; /* filter out private xattrs */ @@ -279,17 +289,16 @@ int ovl_removexattr(struct dentry *dentry, const char *name) { int err; struct path realpath; - enum ovl_path_type type; + enum ovl_path_type type = ovl_path_real(dentry, &realpath); err = ovl_want_write(dentry); if (err) goto out; - if (ovl_path_type(dentry->d_parent) == OVL_PATH_MERGE && - ovl_is_private_xattr(name)) + err = -ENODATA; + if (ovl_need_xattr_filter(dentry, type) && ovl_is_private_xattr(name)) goto out_drop_write; - type = ovl_path_real(dentry, &realpath); if (type == OVL_PATH_LOWER) { err = vfs_getxattr(realpath.dentry, name, NULL, 0); if (err < 0) diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c index 2a7ef4f8e2a6..ab1e3dcbed95 100644 --- a/fs/overlayfs/readdir.c +++ b/fs/overlayfs/readdir.c @@ -274,11 +274,11 @@ static int ovl_dir_mark_whiteouts(struct dentry *dir, return 0; } -static inline int ovl_dir_read_merged(struct path *upperpath, - struct path *lowerpath, - struct list_head *list) +static int ovl_dir_read_merged(struct dentry *dentry, struct list_head *list) { int err; + struct path lowerpath; + struct path upperpath; struct ovl_readdir_data rdd = { .ctx.actor = ovl_fill_merge, .list = list, @@ -286,25 +286,28 @@ static inline int ovl_dir_read_merged(struct path *upperpath, .is_merge = false, }; - if (upperpath->dentry) { - err = ovl_dir_read(upperpath, &rdd); + ovl_path_lower(dentry, &lowerpath); + ovl_path_upper(dentry, &upperpath); + + if (upperpath.dentry) { + err = ovl_dir_read(&upperpath, &rdd); if (err) goto out; - if (lowerpath->dentry) { - err = ovl_dir_mark_whiteouts(upperpath->dentry, &rdd); + if (lowerpath.dentry) { + err = ovl_dir_mark_whiteouts(upperpath.dentry, &rdd); if (err) goto out; } } - if (lowerpath->dentry) { + if (lowerpath.dentry) { /* * Insert lowerpath entries before upperpath ones, this allows * offsets to be reasonably constant */ list_add(&rdd.middle, rdd.list); rdd.is_merge = true; - err = ovl_dir_read(lowerpath, &rdd); + err = ovl_dir_read(&lowerpath, &rdd); list_del(&rdd.middle); } out: @@ -329,8 +332,6 @@ static void ovl_seek_cursor(struct ovl_dir_file *od, loff_t pos) static struct ovl_dir_cache *ovl_cache_get(struct dentry *dentry) { int res; - struct path lowerpath; - struct path upperpath; struct ovl_dir_cache *cache; cache = ovl_dir_cache(dentry); @@ -347,10 +348,7 @@ static struct ovl_dir_cache *ovl_cache_get(struct dentry *dentry) cache->refcount = 1; INIT_LIST_HEAD(&cache->entries); - ovl_path_lower(dentry, &lowerpath); - ovl_path_upper(dentry, &upperpath); - - res = ovl_dir_read_merged(&upperpath, &lowerpath, &cache->entries); + res = ovl_dir_read_merged(dentry, &cache->entries); if (res) { ovl_cache_free(&cache->entries); kfree(cache); @@ -452,10 +450,10 @@ static int ovl_dir_fsync(struct file *file, loff_t start, loff_t end, /* * Need to check if we started out being a lower dir, but got copied up */ - if (!od->is_upper && ovl_path_type(dentry) == OVL_PATH_MERGE) { + if (!od->is_upper && ovl_path_type(dentry) != OVL_PATH_LOWER) { struct inode *inode = file_inode(file); - realfile =lockless_dereference(od->upperfile); + realfile = lockless_dereference(od->upperfile); if (!realfile) { struct path upperpath; @@ -538,14 +536,9 @@ const struct file_operations ovl_dir_operations = { int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list) { int err; - struct path lowerpath; - struct path upperpath; struct ovl_cache_entry *p; - ovl_path_upper(dentry, &upperpath); - ovl_path_lower(dentry, &lowerpath); - - err = ovl_dir_read_merged(&upperpath, &lowerpath, list); + err = ovl_dir_read_merged(dentry, list); if (err) return err; diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 08b704cebfc4..f16d318b71f8 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -24,7 +24,7 @@ MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>"); MODULE_DESCRIPTION("Overlay filesystem"); MODULE_LICENSE("GPL"); -#define OVERLAYFS_SUPER_MAGIC 0x794c764f +#define OVERLAYFS_SUPER_MAGIC 0x794c7630 struct ovl_config { char *lowerdir; @@ -84,12 +84,7 @@ enum ovl_path_type ovl_path_type(struct dentry *dentry) static struct dentry *ovl_upperdentry_dereference(struct ovl_entry *oe) { - struct dentry *upperdentry = ACCESS_ONCE(oe->__upperdentry); - /* - * Make sure to order reads to upperdentry wrt ovl_dentry_update() - */ - smp_read_barrier_depends(); - return upperdentry; + return lockless_dereference(oe->__upperdentry); } void ovl_path_upper(struct dentry *dentry, struct path *path) @@ -462,11 +457,34 @@ static const match_table_t ovl_tokens = { {OPT_ERR, NULL} }; +static char *ovl_next_opt(char **s) +{ + char *sbegin = *s; + char *p; + + if (sbegin == NULL) + return NULL; + + for (p = sbegin; *p; p++) { + if (*p == '\\') { + p++; + if (!*p) + break; + } else if (*p == ',') { + *p = '\0'; + *s = p + 1; + return sbegin; + } + } + *s = NULL; + return sbegin; +} + static int ovl_parse_opt(char *opt, struct ovl_config *config) { char *p; - while ((p = strsep(&opt, ",")) != NULL) { + while ((p = ovl_next_opt(&opt)) != NULL) { int token; substring_t args[MAX_OPT_ARGS]; @@ -554,15 +572,34 @@ out_dput: goto out_unlock; } +static void ovl_unescape(char *s) +{ + char *d = s; + + for (;; s++, d++) { + if (*s == '\\') + s++; + *d = *s; + if (!*s) + break; + } +} + static int ovl_mount_dir(const char *name, struct path *path) { int err; + char *tmp = kstrdup(name, GFP_KERNEL); + + if (!tmp) + return -ENOMEM; - err = kern_path(name, LOOKUP_FOLLOW, path); + ovl_unescape(tmp); + err = kern_path(tmp, LOOKUP_FOLLOW, path); if (err) { - pr_err("overlayfs: failed to resolve '%s': %i\n", name, err); + pr_err("overlayfs: failed to resolve '%s': %i\n", tmp, err); err = -EINVAL; } + kfree(tmp); return err; } @@ -776,11 +813,11 @@ static struct dentry *ovl_mount(struct file_system_type *fs_type, int flags, static struct file_system_type ovl_fs_type = { .owner = THIS_MODULE, - .name = "overlayfs", + .name = "overlay", .mount = ovl_mount, .kill_sb = kill_anon_super, }; -MODULE_ALIAS_FS("overlayfs"); +MODULE_ALIAS_FS("overlay"); static int __init ovl_init(void) { |