X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=fs%2Fnamei.c;h=71c0b93a480095a69dd0491b326d8989f2cdfe57;hb=a1bd55431114f35158e3c5a46db754fd74c55889;hp=95a881e0552b1d6ca6333a47ae7c006a9455b29b;hpb=4e1c754472ffbf251835fc01f4cc638ffa8dd576;p=platform%2Fkernel%2Flinux-rpi.git diff --git a/fs/namei.c b/fs/namei.c index 95a881e..71c0b93 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -255,7 +255,7 @@ getname_kernel(const char * filename) void putname(struct filename *name) { - if (IS_ERR_OR_NULL(name)) + if (IS_ERR(name)) return; BUG_ON(name->refcnt <= 0); @@ -1461,6 +1461,8 @@ static bool __follow_mount_rcu(struct nameidata *nd, struct path *path, * becoming unpinned. */ flags = dentry->d_flags; + if (read_seqretry(&mount_lock, nd->m_seq)) + return false; continue; } if (read_seqretry(&mount_lock, nd->m_seq)) @@ -1633,7 +1635,7 @@ static struct dentry *__lookup_slow(const struct qstr *name, { struct dentry *dentry, *old; struct inode *inode = dir->d_inode; - DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); + DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq); /* Don't go there if it's already dead */ if (unlikely(IS_DEADDIR(inode))) @@ -2467,7 +2469,7 @@ static int path_lookupat(struct nameidata *nd, unsigned flags, struct path *path return err; } -static int __filename_lookup(int dfd, struct filename *name, unsigned flags, +int filename_lookup(int dfd, struct filename *name, unsigned flags, struct path *path, struct path *root) { int retval; @@ -2488,15 +2490,6 @@ static int __filename_lookup(int dfd, struct filename *name, unsigned flags, return retval; } -int filename_lookup(int dfd, struct filename *name, unsigned flags, - struct path *path, struct path *root) -{ - int retval = __filename_lookup(dfd, name, flags, path, root); - - putname(name); - return retval; -} - /* Returns 0 and nd will be valid on success; Retuns error, otherwise. */ static int path_parentat(struct nameidata *nd, unsigned flags, struct path *parent) @@ -2514,9 +2507,10 @@ static int path_parentat(struct nameidata *nd, unsigned flags, return err; } -static int __filename_parentat(int dfd, struct filename *name, - unsigned int flags, struct path *parent, - struct qstr *last, int *type) +/* Note: this does not consume "name" */ +static int filename_parentat(int dfd, struct filename *name, + unsigned int flags, struct path *parent, + struct qstr *last, int *type) { int retval; struct nameidata nd; @@ -2538,25 +2532,14 @@ static int __filename_parentat(int dfd, struct filename *name, return retval; } -static int filename_parentat(int dfd, struct filename *name, - unsigned int flags, struct path *parent, - struct qstr *last, int *type) -{ - int retval = __filename_parentat(dfd, name, flags, parent, last, type); - - putname(name); - return retval; -} - /* does lookup, returns the object with parent locked */ -struct dentry *kern_path_locked(const char *name, struct path *path) +static struct dentry *__kern_path_locked(struct filename *name, struct path *path) { struct dentry *d; struct qstr last; int type, error; - error = filename_parentat(AT_FDCWD, getname_kernel(name), 0, path, - &last, &type); + error = filename_parentat(AT_FDCWD, name, 0, path, &last, &type); if (error) return ERR_PTR(error); if (unlikely(type != LAST_NORM)) { @@ -2572,10 +2555,23 @@ struct dentry *kern_path_locked(const char *name, struct path *path) return d; } +struct dentry *kern_path_locked(const char *name, struct path *path) +{ + struct filename *filename = getname_kernel(name); + struct dentry *res = __kern_path_locked(filename, path); + + putname(filename); + return res; +} + int kern_path(const char *name, unsigned int flags, struct path *path) { - return filename_lookup(AT_FDCWD, getname_kernel(name), - flags, path, NULL); + struct filename *filename = getname_kernel(name); + int ret = filename_lookup(AT_FDCWD, filename, flags, path, NULL); + + putname(filename); + return ret; + } EXPORT_SYMBOL(kern_path); @@ -2591,10 +2587,15 @@ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt, const char *name, unsigned int flags, struct path *path) { + struct filename *filename; struct path root = {.mnt = mnt, .dentry = dentry}; + int ret; + + filename = getname_kernel(name); /* the first argument of filename_lookup() is ignored with root */ - return filename_lookup(AT_FDCWD, getname_kernel(name), - flags , path, &root); + ret = filename_lookup(AT_FDCWD, filename, flags, path, &root); + putname(filename); + return ret; } EXPORT_SYMBOL(vfs_path_lookup); @@ -2719,7 +2720,8 @@ struct dentry *lookup_one(struct user_namespace *mnt_userns, const char *name, EXPORT_SYMBOL(lookup_one); /** - * lookup_one_len_unlocked - filesystem helper to lookup single pathname component + * lookup_one_unlocked - filesystem helper to lookup single pathname component + * @mnt_userns: idmapping of the mount the lookup is performed from * @name: pathname component to lookup * @base: base directory to lookup from * @len: maximum length @len should be interpreted to @@ -2730,14 +2732,15 @@ EXPORT_SYMBOL(lookup_one); * Unlike lookup_one_len, it should be called without the parent * i_mutex held, and will take the i_mutex itself if necessary. */ -struct dentry *lookup_one_len_unlocked(const char *name, - struct dentry *base, int len) +struct dentry *lookup_one_unlocked(struct user_namespace *mnt_userns, + const char *name, struct dentry *base, + int len) { struct qstr this; int err; struct dentry *ret; - err = lookup_one_common(&init_user_ns, name, base, len, &this); + err = lookup_one_common(mnt_userns, name, base, len, &this); if (err) return ERR_PTR(err); @@ -2746,6 +2749,59 @@ struct dentry *lookup_one_len_unlocked(const char *name, ret = lookup_slow(&this, base, 0); return ret; } +EXPORT_SYMBOL(lookup_one_unlocked); + +/** + * lookup_one_positive_unlocked - filesystem helper to lookup single + * pathname component + * @mnt_userns: idmapping of the mount the lookup is performed from + * @name: pathname component to lookup + * @base: base directory to lookup from + * @len: maximum length @len should be interpreted to + * + * This helper will yield ERR_PTR(-ENOENT) on negatives. The helper returns + * known positive or ERR_PTR(). This is what most of the users want. + * + * Note that pinned negative with unlocked parent _can_ become positive at any + * time, so callers of lookup_one_unlocked() need to be very careful; pinned + * positives have >d_inode stable, so this one avoids such problems. + * + * Note that this routine is purely a helper for filesystem usage and should + * not be called by generic code. + * + * The helper should be called without i_mutex held. + */ +struct dentry *lookup_one_positive_unlocked(struct user_namespace *mnt_userns, + const char *name, + struct dentry *base, int len) +{ + struct dentry *ret = lookup_one_unlocked(mnt_userns, name, base, len); + + if (!IS_ERR(ret) && d_flags_negative(smp_load_acquire(&ret->d_flags))) { + dput(ret); + ret = ERR_PTR(-ENOENT); + } + return ret; +} +EXPORT_SYMBOL(lookup_one_positive_unlocked); + +/** + * lookup_one_len_unlocked - filesystem helper to lookup single pathname component + * @name: pathname component to lookup + * @base: base directory to lookup from + * @len: maximum length @len should be interpreted to + * + * Note that this routine is purely a helper for filesystem usage and should + * not be called by generic code. + * + * Unlike lookup_one_len, it should be called without the parent + * i_mutex held, and will take the i_mutex itself if necessary. + */ +struct dentry *lookup_one_len_unlocked(const char *name, + struct dentry *base, int len) +{ + return lookup_one_unlocked(&init_user_ns, name, base, len); +} EXPORT_SYMBOL(lookup_one_len_unlocked); /* @@ -2759,12 +2815,7 @@ EXPORT_SYMBOL(lookup_one_len_unlocked); struct dentry *lookup_positive_unlocked(const char *name, struct dentry *base, int len) { - struct dentry *ret = lookup_one_len_unlocked(name, base, len); - if (!IS_ERR(ret) && d_flags_negative(smp_load_acquire(&ret->d_flags))) { - dput(ret); - ret = ERR_PTR(-ENOENT); - } - return ret; + return lookup_one_positive_unlocked(&init_user_ns, name, base, len); } EXPORT_SYMBOL(lookup_positive_unlocked); @@ -2798,8 +2849,11 @@ int path_pts(struct path *path) int user_path_at_empty(int dfd, const char __user *name, unsigned flags, struct path *path, int *empty) { - return filename_lookup(dfd, getname_flags(name, flags, empty), - flags, path, NULL); + struct filename *filename = getname_flags(name, flags, empty); + int ret = filename_lookup(dfd, filename, flags, path, NULL); + + putname(filename); + return ret; } EXPORT_SYMBOL(user_path_at_empty); @@ -3192,7 +3246,7 @@ static struct dentry *lookup_open(struct nameidata *nd, struct file *file, struct dentry *dentry; int error, create_error = 0; umode_t mode = op->mode; - DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); + DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq); if (unlikely(IS_DEADDIR(dir_inode))) return ERR_PTR(-ENOENT); @@ -3471,6 +3525,8 @@ struct dentry *vfs_tmpfile(struct user_namespace *mnt_userns, child = d_alloc(dentry, &slash_name); if (unlikely(!child)) goto out_err; + if (!IS_POSIXACL(dir)) + mode &= ~current_umask(); error = dir->i_op->tmpfile(mnt_userns, dir, child, mode); if (error) goto out_err; @@ -3618,23 +3674,19 @@ struct file *do_file_open_root(const struct path *root, return file; } -static struct dentry *__filename_create(int dfd, struct filename *name, - struct path *path, unsigned int lookup_flags) +static struct dentry *filename_create(int dfd, struct filename *name, + struct path *path, unsigned int lookup_flags) { struct dentry *dentry = ERR_PTR(-EEXIST); struct qstr last; + bool want_dir = lookup_flags & LOOKUP_DIRECTORY; + unsigned int reval_flag = lookup_flags & LOOKUP_REVAL; + unsigned int create_flags = LOOKUP_CREATE | LOOKUP_EXCL; int type; int err2; int error; - bool is_dir = (lookup_flags & LOOKUP_DIRECTORY); - /* - * Note that only LOOKUP_REVAL and LOOKUP_DIRECTORY matter here. Any - * other flags passed in are ignored! - */ - lookup_flags &= LOOKUP_REVAL; - - error = __filename_parentat(dfd, name, lookup_flags, path, &last, &type); + error = filename_parentat(dfd, name, reval_flag, path, &last, &type); if (error) return ERR_PTR(error); @@ -3648,11 +3700,13 @@ static struct dentry *__filename_create(int dfd, struct filename *name, /* don't fail immediately if it's r/o, at least try to report other errors */ err2 = mnt_want_write(path->mnt); /* - * Do the final lookup. + * Do the final lookup. Suppress 'create' if there is a trailing + * '/', and a directory wasn't requested. */ - lookup_flags |= LOOKUP_CREATE | LOOKUP_EXCL; + if (last.name[last.len] && !want_dir) + create_flags = 0; inode_lock_nested(path->dentry->d_inode, I_MUTEX_PARENT); - dentry = __lookup_hash(&last, path->dentry, lookup_flags); + dentry = __lookup_hash(&last, path->dentry, reval_flag | create_flags); if (IS_ERR(dentry)) goto unlock; @@ -3666,7 +3720,7 @@ static struct dentry *__filename_create(int dfd, struct filename *name, * all is fine. Let's be bastards - you had / on the end, you've * been asking for (non-existent) directory. -ENOENT for you. */ - if (unlikely(!is_dir && last.name[last.len])) { + if (unlikely(!create_flags)) { error = -ENOENT; goto fail; } @@ -3687,21 +3741,15 @@ out: return dentry; } -static inline struct dentry *filename_create(int dfd, struct filename *name, +struct dentry *kern_path_create(int dfd, const char *pathname, struct path *path, unsigned int lookup_flags) { - struct dentry *res = __filename_create(dfd, name, path, lookup_flags); + struct filename *filename = getname_kernel(pathname); + struct dentry *res = filename_create(dfd, filename, path, lookup_flags); - putname(name); + putname(filename); return res; } - -struct dentry *kern_path_create(int dfd, const char *pathname, - struct path *path, unsigned int lookup_flags) -{ - return filename_create(dfd, getname_kernel(pathname), - path, lookup_flags); -} EXPORT_SYMBOL(kern_path_create); void done_path_create(struct path *path, struct dentry *dentry) @@ -3716,7 +3764,11 @@ EXPORT_SYMBOL(done_path_create); inline struct dentry *user_path_create(int dfd, const char __user *pathname, struct path *path, unsigned int lookup_flags) { - return filename_create(dfd, getname(pathname), path, lookup_flags); + struct filename *filename = getname(pathname); + struct dentry *res = filename_create(dfd, filename, path, lookup_flags); + + putname(filename); + return res; } EXPORT_SYMBOL(user_path_create); @@ -3797,7 +3849,7 @@ static int do_mknodat(int dfd, struct filename *name, umode_t mode, if (error) goto out1; retry: - dentry = __filename_create(dfd, name, &path, lookup_flags); + dentry = filename_create(dfd, name, &path, lookup_flags); error = PTR_ERR(dentry); if (IS_ERR(dentry)) goto out1; @@ -3897,7 +3949,7 @@ int do_mkdirat(int dfd, struct filename *name, umode_t mode) unsigned int lookup_flags = LOOKUP_DIRECTORY; retry: - dentry = __filename_create(dfd, name, &path, lookup_flags); + dentry = filename_create(dfd, name, &path, lookup_flags); error = PTR_ERR(dentry); if (IS_ERR(dentry)) goto out_putname; @@ -3975,13 +4027,12 @@ int vfs_rmdir(struct user_namespace *mnt_userns, struct inode *dir, dentry->d_inode->i_flags |= S_DEAD; dont_mount(dentry); detach_mounts(dentry); - fsnotify_rmdir(dir, dentry); out: inode_unlock(dentry->d_inode); dput(dentry); if (!error) - d_delete(dentry); + d_delete_notify(dir, dentry); return error; } EXPORT_SYMBOL(vfs_rmdir); @@ -3996,7 +4047,7 @@ int do_rmdir(int dfd, struct filename *name) int type; unsigned int lookup_flags = 0; retry: - error = __filename_parentat(dfd, name, lookup_flags, &path, &last, &type); + error = filename_parentat(dfd, name, lookup_flags, &path, &last, &type); if (error) goto exit1; @@ -4103,7 +4154,6 @@ int vfs_unlink(struct user_namespace *mnt_userns, struct inode *dir, if (!error) { dont_mount(dentry); detach_mounts(dentry); - fsnotify_unlink(dir, dentry); } } } @@ -4111,9 +4161,11 @@ out: inode_unlock(target); /* We don't d_delete() NFS sillyrenamed files--they still exist. */ - if (!error && !(dentry->d_flags & DCACHE_NFSFS_RENAMED)) { + if (!error && dentry->d_flags & DCACHE_NFSFS_RENAMED) { + fsnotify_unlink(dir, dentry); + } else if (!error) { fsnotify_link_count(target); - d_delete(dentry); + d_delete_notify(dir, dentry); } return error; @@ -4137,7 +4189,7 @@ int do_unlinkat(int dfd, struct filename *name) struct inode *delegated_inode = NULL; unsigned int lookup_flags = 0; retry: - error = __filename_parentat(dfd, name, lookup_flags, &path, &last, &type); + error = filename_parentat(dfd, name, lookup_flags, &path, &last, &type); if (error) goto exit1; @@ -4266,7 +4318,7 @@ int do_symlinkat(struct filename *from, int newdfd, struct filename *to) goto out_putnames; } retry: - dentry = __filename_create(newdfd, to, &path, lookup_flags); + dentry = filename_create(newdfd, to, &path, lookup_flags); error = PTR_ERR(dentry); if (IS_ERR(dentry)) goto out_putnames; @@ -4426,11 +4478,11 @@ int do_linkat(int olddfd, struct filename *old, int newdfd, if (flags & AT_SYMLINK_FOLLOW) how |= LOOKUP_FOLLOW; retry: - error = __filename_lookup(olddfd, old, how, &old_path, NULL); + error = filename_lookup(olddfd, old, how, &old_path, NULL); if (error) goto out_putnames; - new_dentry = __filename_create(newdfd, new, &new_path, + new_dentry = filename_create(newdfd, new, &new_path, (how & LOOKUP_REVAL)); error = PTR_ERR(new_dentry); if (IS_ERR(new_dentry)) @@ -4689,13 +4741,13 @@ int do_renameat2(int olddfd, struct filename *from, int newdfd, target_flags = 0; retry: - error = __filename_parentat(olddfd, from, lookup_flags, &old_path, - &old_last, &old_type); + error = filename_parentat(olddfd, from, lookup_flags, &old_path, + &old_last, &old_type); if (error) goto put_names; - error = __filename_parentat(newdfd, to, lookup_flags, &new_path, &new_last, - &new_type); + error = filename_parentat(newdfd, to, lookup_flags, &new_path, &new_last, + &new_type); if (error) goto exit1;