1 files changed, 122 insertions, 76 deletions

diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 494ac372ace0..2d817d7cab26 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -175,9 +175,12 @@ static void fuse_lookup_init(struct fuse_conn *fc, struct fuse_args *args,
 	memset(outarg, 0, sizeof(struct fuse_entry_out));
 	args->opcode = FUSE_LOOKUP;
 	args->nodeid = nodeid;
-	args->in_numargs = 1;
-	args->in_args[0].size = name->len + 1;
-	args->in_args[0].value = name->name;
+	args->in_numargs = 3;
+	fuse_set_zero_arg0(args);
+	args->in_args[1].size = name->len;
+	args->in_args[1].value = name->name;
+	args->in_args[2].size = 1;
+	args->in_args[2].value = "";
 	args->out_numargs = 1;
 	args->out_args[0].size = sizeof(struct fuse_entry_out);
 	args->out_args[0].value = outarg;
@@ -192,14 +195,19 @@ static void fuse_lookup_init(struct fuse_conn *fc, struct fuse_args *args,
  * the lookup once more.  If the lookup results in the same inode,
  * then refresh the attributes, timeouts and mark the dentry valid.
  */
-static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags)
+static int fuse_dentry_revalidate(struct inode *dir, const struct qstr *name,
+				  struct dentry *entry, unsigned int flags)
 {
 	struct inode *inode;
-	struct dentry *parent;
 	struct fuse_mount *fm;
+	struct fuse_conn *fc;
 	struct fuse_inode *fi;
 	int ret;
 
+	fc = get_fuse_conn_super(dir->i_sb);
+	if (entry->d_time < atomic_read(&fc->epoch))
+		goto invalid;
+
 	inode = d_inode_rcu(entry);
 	if (inode && fuse_is_bad(inode))
 		goto invalid;
@@ -227,11 +235,9 @@ static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags)
 
 		attr_version = fuse_get_attr_version(fm->fc);
 
-		parent = dget_parent(entry);
-		fuse_lookup_init(fm->fc, &args, get_node_id(d_inode(parent)),
-				 &entry->d_name, &outarg);
+		fuse_lookup_init(fm->fc, &args, get_node_id(dir),
+				 name, &outarg);
 		ret = fuse_simple_request(fm, &args);
-		dput(parent);
 		/* Zero nodeid is same as -ENOENT */
 		if (!ret && !outarg.nodeid)
 			ret = -ENOENT;
@@ -265,9 +271,7 @@ static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags)
 			if (test_bit(FUSE_I_INIT_RDPLUS, &fi->state))
 				return -ECHILD;
 		} else if (test_and_clear_bit(FUSE_I_INIT_RDPLUS, &fi->state)) {
-			parent = dget_parent(entry);
-			fuse_advise_use_readdirplus(d_inode(parent));
-			dput(parent);
+			fuse_advise_use_readdirplus(dir);
 		}
 	}
 	ret = 1;
@@ -320,9 +324,6 @@ static struct vfsmount *fuse_dentry_automount(struct path *path)
 
 	/* Create the submount */
 	mnt = fc_mount(fsc);
-	if (!IS_ERR(mnt))
-		mntget(mnt);
-
 	put_fs_context(fsc);
 	return mnt;
 }
@@ -337,13 +338,6 @@ const struct dentry_operations fuse_dentry_operations = {
 	.d_automount	= fuse_dentry_automount,
 };
 
-const struct dentry_operations fuse_root_dentry_operations = {
-#if BITS_PER_LONG < 64
-	.d_init		= fuse_dentry_init,
-	.d_release	= fuse_dentry_release,
-#endif
-};
-
 int fuse_valid_type(int m)
 {
 	return S_ISREG(m) || S_ISDIR(m) || S_ISLNK(m) || S_ISCHR(m) ||
@@ -371,7 +365,7 @@ int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name
 
 	*inode = NULL;
 	err = -ENAMETOOLONG;
-	if (name->len > FUSE_NAME_MAX)
+	if (name->len > fm->fc->name_max)
 		goto out;
 
 
@@ -416,16 +410,20 @@ int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name
 static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
 				  unsigned int flags)
 {
-	int err;
 	struct fuse_entry_out outarg;
+	struct fuse_conn *fc;
 	struct inode *inode;
 	struct dentry *newent;
+	int err, epoch;
 	bool outarg_valid = true;
 	bool locked;
 
 	if (fuse_is_bad(dir))
 		return ERR_PTR(-EIO);
 
+	fc = get_fuse_conn_super(dir->i_sb);
+	epoch = atomic_read(&fc->epoch);
+
 	locked = fuse_lock_inode(dir);
 	err = fuse_lookup_name(dir->i_sb, get_node_id(dir), &entry->d_name,
 			       &outarg, &inode);
@@ -447,6 +445,7 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
 		goto out_err;
 
 	entry = newent ? newent : entry;
+	entry->d_time = epoch;
 	if (outarg_valid)
 		fuse_change_entry_timeout(entry, &outarg);
 	else
@@ -467,29 +466,29 @@ static int get_security_context(struct dentry *entry, umode_t mode,
 {
 	struct fuse_secctx *fctx;
 	struct fuse_secctx_header *header;
-	void *ctx = NULL, *ptr;
-	u32 ctxlen, total_len = sizeof(*header);
+	struct lsm_context lsmctx = { };
+	void *ptr;
+	u32 total_len = sizeof(*header);
 	int err, nr_ctx = 0;
-	const char *name;
+	const char *name = NULL;
 	size_t namelen;
 
 	err = security_dentry_init_security(entry, mode, &entry->d_name,
-					    &name, &ctx, &ctxlen);
-	if (err) {
-		if (err != -EOPNOTSUPP)
-			goto out_err;
-		/* No LSM is supporting this security hook. Ignore error */
-		ctxlen = 0;
-		ctx = NULL;
-	}
+					    &name, &lsmctx);
 
-	if (ctxlen) {
+	/* If no LSM is supporting this security hook ignore error */
+	if (err && err != -EOPNOTSUPP)
+		goto out_err;
+
+	if (lsmctx.len) {
 		nr_ctx = 1;
 		namelen = strlen(name) + 1;
 		err = -EIO;
-		if (WARN_ON(namelen > XATTR_NAME_MAX + 1 || ctxlen > S32_MAX))
+		if (WARN_ON(namelen > XATTR_NAME_MAX + 1 ||
+		    lsmctx.len > S32_MAX))
 			goto out_err;
-		total_len += FUSE_REC_ALIGN(sizeof(*fctx) + namelen + ctxlen);
+		total_len += FUSE_REC_ALIGN(sizeof(*fctx) + namelen +
+					    lsmctx.len);
 	}
 
 	err = -ENOMEM;
@@ -502,19 +501,20 @@ static int get_security_context(struct dentry *entry, umode_t mode,
 	ptr += sizeof(*header);
 	if (nr_ctx) {
 		fctx = ptr;
-		fctx->size = ctxlen;
+		fctx->size = lsmctx.len;
 		ptr += sizeof(*fctx);
 
 		strcpy(ptr, name);
 		ptr += namelen;
 
-		memcpy(ptr, ctx, ctxlen);
+		memcpy(ptr, lsmctx.context, lsmctx.len);
 	}
 	ext->size = total_len;
 	ext->value = header;
 	err = 0;
 out_err:
-	kfree(ctx);
+	if (nr_ctx)
+		security_release_secctx(&lsmctx);
 	return err;
 }
 
@@ -619,7 +619,6 @@ static int fuse_create_open(struct mnt_idmap *idmap, struct inode *dir,
 			    struct dentry *entry, struct file *file,
 			    unsigned int flags, umode_t mode, u32 opcode)
 {
-	int err;
 	struct inode *inode;
 	struct fuse_mount *fm = get_fuse_mount(dir);
 	FUSE_ARGS(args);
@@ -629,11 +628,13 @@ static int fuse_create_open(struct mnt_idmap *idmap, struct inode *dir,
 	struct fuse_entry_out outentry;
 	struct fuse_inode *fi;
 	struct fuse_file *ff;
+	int epoch, err;
 	bool trunc = flags & O_TRUNC;
 
 	/* Userspace expects S_IFREG in create mode */
 	BUG_ON((mode & S_IFMT) != S_IFREG);
 
+	epoch = atomic_read(&fm->fc->epoch);
 	forget = fuse_alloc_forget();
 	err = -ENOMEM;
 	if (!forget)
@@ -702,6 +703,7 @@ static int fuse_create_open(struct mnt_idmap *idmap, struct inode *dir,
 	}
 	kfree(forget);
 	d_instantiate(entry, inode);
+	entry->d_time = epoch;
 	fuse_change_entry_timeout(entry, &outentry);
 	fuse_dir_changed(dir);
 	err = generic_file_open(inode, file);
@@ -781,22 +783,24 @@ no_open:
 /*
  * Code shared between mknod, mkdir, symlink and link
  */
-static int create_new_entry(struct mnt_idmap *idmap, struct fuse_mount *fm,
-			    struct fuse_args *args, struct inode *dir,
-			    struct dentry *entry, umode_t mode)
+static struct dentry *create_new_entry(struct mnt_idmap *idmap, struct fuse_mount *fm,
+				       struct fuse_args *args, struct inode *dir,
+				       struct dentry *entry, umode_t mode)
 {
 	struct fuse_entry_out outarg;
 	struct inode *inode;
 	struct dentry *d;
-	int err;
 	struct fuse_forget_link *forget;
+	int epoch, err;
 
 	if (fuse_is_bad(dir))
-		return -EIO;
+		return ERR_PTR(-EIO);
+
+	epoch = atomic_read(&fm->fc->epoch);
 
 	forget = fuse_alloc_forget();
 	if (!forget)
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 
 	memset(&outarg, 0, sizeof(outarg));
 	args->nodeid = get_node_id(dir);
@@ -826,29 +830,46 @@ static int create_new_entry(struct mnt_idmap *idmap, struct fuse_mount *fm,
 			  &outarg.attr, ATTR_TIMEOUT(&outarg), 0, 0);
 	if (!inode) {
 		fuse_queue_forget(fm->fc, forget, outarg.nodeid, 1);
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 	}
 	kfree(forget);
 
 	d_drop(entry);
 	d = d_splice_alias(inode, entry);
 	if (IS_ERR(d))
-		return PTR_ERR(d);
+		return d;
 
 	if (d) {
+		d->d_time = epoch;
 		fuse_change_entry_timeout(d, &outarg);
-		dput(d);
 	} else {
+		entry->d_time = epoch;
 		fuse_change_entry_timeout(entry, &outarg);
 	}
 	fuse_dir_changed(dir);
-	return 0;
+	return d;
 
  out_put_forget_req:
 	if (err == -EEXIST)
 		fuse_invalidate_entry(entry);
 	kfree(forget);
-	return err;
+	return ERR_PTR(err);
+}
+
+static int create_new_nondir(struct mnt_idmap *idmap, struct fuse_mount *fm,
+			     struct fuse_args *args, struct inode *dir,
+			     struct dentry *entry, umode_t mode)
+{
+	/*
+	 * Note that when creating anything other than a directory we
+	 * can be sure create_new_entry() will NOT return an alternate
+	 * dentry as d_splice_alias() only returns an alternate dentry
+	 * for directories.  So we don't need to check for that case
+	 * when passing back the result.
+	 */
+	WARN_ON_ONCE(S_ISDIR(mode));
+
+	return PTR_ERR(create_new_entry(idmap, fm, args, dir, entry, mode));
 }
 
 static int fuse_mknod(struct mnt_idmap *idmap, struct inode *dir,
@@ -871,7 +892,7 @@ static int fuse_mknod(struct mnt_idmap *idmap, struct inode *dir,
 	args.in_args[0].value = &inarg;
 	args.in_args[1].size = entry->d_name.len + 1;
 	args.in_args[1].value = entry->d_name.name;
-	return create_new_entry(idmap, fm, &args, dir, entry, mode);
+	return create_new_nondir(idmap, fm, &args, dir, entry, mode);
 }
 
 static int fuse_create(struct mnt_idmap *idmap, struct inode *dir,
@@ -898,8 +919,8 @@ static int fuse_tmpfile(struct mnt_idmap *idmap, struct inode *dir,
 	return err;
 }
 
-static int fuse_mkdir(struct mnt_idmap *idmap, struct inode *dir,
-		      struct dentry *entry, umode_t mode)
+static struct dentry *fuse_mkdir(struct mnt_idmap *idmap, struct inode *dir,
+				 struct dentry *entry, umode_t mode)
 {
 	struct fuse_mkdir_in inarg;
 	struct fuse_mount *fm = get_fuse_mount(dir);
@@ -928,12 +949,13 @@ static int fuse_symlink(struct mnt_idmap *idmap, struct inode *dir,
 	FUSE_ARGS(args);
 
 	args.opcode = FUSE_SYMLINK;
-	args.in_numargs = 2;
-	args.in_args[0].size = entry->d_name.len + 1;
-	args.in_args[0].value = entry->d_name.name;
-	args.in_args[1].size = len;
-	args.in_args[1].value = link;
-	return create_new_entry(idmap, fm, &args, dir, entry, S_IFLNK);
+	args.in_numargs = 3;
+	fuse_set_zero_arg0(&args);
+	args.in_args[1].size = entry->d_name.len + 1;
+	args.in_args[1].value = entry->d_name.name;
+	args.in_args[2].size = len;
+	args.in_args[2].value = link;
+	return create_new_nondir(idmap, fm, &args, dir, entry, S_IFLNK);
 }
 
 void fuse_flush_time_update(struct inode *inode)
@@ -992,9 +1014,10 @@ static int fuse_unlink(struct inode *dir, struct dentry *entry)
 
 	args.opcode = FUSE_UNLINK;
 	args.nodeid = get_node_id(dir);
-	args.in_numargs = 1;
-	args.in_args[0].size = entry->d_name.len + 1;
-	args.in_args[0].value = entry->d_name.name;
+	args.in_numargs = 2;
+	fuse_set_zero_arg0(&args);
+	args.in_args[1].size = entry->d_name.len + 1;
+	args.in_args[1].value = entry->d_name.name;
 	err = fuse_simple_request(fm, &args);
 	if (!err) {
 		fuse_dir_changed(dir);
@@ -1015,9 +1038,10 @@ static int fuse_rmdir(struct inode *dir, struct dentry *entry)
 
 	args.opcode = FUSE_RMDIR;
 	args.nodeid = get_node_id(dir);
-	args.in_numargs = 1;
-	args.in_args[0].size = entry->d_name.len + 1;
-	args.in_args[0].value = entry->d_name.name;
+	args.in_numargs = 2;
+	fuse_set_zero_arg0(&args);
+	args.in_args[1].size = entry->d_name.len + 1;
+	args.in_args[1].value = entry->d_name.name;
 	err = fuse_simple_request(fm, &args);
 	if (!err) {
 		fuse_dir_changed(dir);
@@ -1120,6 +1144,9 @@ static int fuse_link(struct dentry *entry, struct inode *newdir,
 	struct fuse_mount *fm = get_fuse_mount(inode);
 	FUSE_ARGS(args);
 
+	if (fm->fc->no_link)
+		goto out;
+
 	memset(&inarg, 0, sizeof(inarg));
 	inarg.oldnodeid = get_node_id(inode);
 	args.opcode = FUSE_LINK;
@@ -1128,12 +1155,18 @@ static int fuse_link(struct dentry *entry, struct inode *newdir,
 	args.in_args[0].value = &inarg;
 	args.in_args[1].size = newent->d_name.len + 1;
 	args.in_args[1].value = newent->d_name.name;
-	err = create_new_entry(&invalid_mnt_idmap, fm, &args, newdir, newent, inode->i_mode);
+	err = create_new_nondir(&invalid_mnt_idmap, fm, &args, newdir, newent, inode->i_mode);
 	if (!err)
 		fuse_update_ctime_in_cache(inode);
 	else if (err == -EINTR)
 		fuse_invalidate_attr(inode);
 
+	if (err == -ENOSYS)
+		fm->fc->no_link = 1;
+out:
+	if (fm->fc->no_link)
+		return -EPERM;
+
 	return err;
 }
 
@@ -1586,10 +1619,10 @@ static int fuse_permission(struct mnt_idmap *idmap,
 	return err;
 }
 
-static int fuse_readlink_page(struct inode *inode, struct folio *folio)
+static int fuse_readlink_folio(struct inode *inode, struct folio *folio)
 {
 	struct fuse_mount *fm = get_fuse_mount(inode);
-	struct fuse_folio_desc desc = { .length = PAGE_SIZE - 1 };
+	struct fuse_folio_desc desc = { .length = folio_size(folio) - 1 };
 	struct fuse_args_pages ap = {
 		.num_folios = 1,
 		.folios = &folio,
@@ -1633,7 +1666,7 @@ static const char *fuse_get_link(struct dentry *dentry, struct inode *inode,
 		goto out_err;
 
 	if (fc->cache_symlinks)
-		return page_get_link(dentry, inode, callback);
+		return page_get_link_raw(dentry, inode, callback);
 
 	err = -ECHILD;
 	if (!dentry)
@@ -1644,13 +1677,13 @@ static const char *fuse_get_link(struct dentry *dentry, struct inode *inode,
 	if (!folio)
 		goto out_err;
 
-	err = fuse_readlink_page(inode, folio);
+	err = fuse_readlink_folio(inode, folio);
 	if (err) {
 		folio_put(folio);
 		goto out_err;
 	}
 
-	set_delayed_call(callback, page_put_link, &folio->page);
+	set_delayed_call(callback, page_put_link, folio);
 
 	return folio_address(folio);
 
@@ -1681,6 +1714,8 @@ static int fuse_dir_open(struct inode *inode, struct file *file)
 		 */
 		if (ff->open_flags & (FOPEN_STREAM | FOPEN_NONSEEKABLE))
 			nonseekable_open(inode, file);
+		if (!(ff->open_flags & FOPEN_KEEP_CACHE))
+			invalidate_inode_pages2(inode->i_mapping);
 	}
 
 	return err;
@@ -1918,6 +1953,7 @@ int fuse_do_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 	int err;
 	bool trust_local_cmtime = is_wb;
 	bool fault_blocked = false;
+	u64 attr_version;
 
 	if (!fc->default_permissions)
 		attr->ia_valid |= ATTR_FORCE;
@@ -1935,7 +1971,7 @@ int fuse_do_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 	if (FUSE_IS_DAX(inode) && is_truncate) {
 		filemap_invalidate_lock(mapping);
 		fault_blocked = true;
-		err = fuse_dax_break_layouts(inode, 0, 0);
+		err = fuse_dax_break_layouts(inode, 0, -1);
 		if (err) {
 			filemap_invalidate_unlock(mapping);
 			return err;
@@ -2002,6 +2038,8 @@ int fuse_do_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 		if (fc->handle_killpriv_v2 && !capable(CAP_FSETID))
 			inarg.valid |= FATTR_KILL_SUIDGID;
 	}
+
+	attr_version = fuse_get_attr_version(fm->fc);
 	fuse_setattr_fill(fc, &args, inode, &inarg, &outarg);
 	err = fuse_simple_request(fm, &args);
 	if (err) {
@@ -2027,6 +2065,14 @@ int fuse_do_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 		/* FIXME: clear I_DIRTY_SYNC? */
 	}
 
+	if (fi->attr_version > attr_version) {
+		/*
+		 * Apply attributes, for example for fsnotify_change(), but set
+		 * attribute timeout to zero.
+		 */
+		outarg.attr_valid = outarg.attr_valid_nsec = 0;
+	}
+
 	fuse_change_attributes_common(inode, &outarg.attr, NULL,
 				      ATTR_TIMEOUT(&outarg),
 				      fuse_get_cache_mask(inode), 0);
@@ -2232,7 +2278,7 @@ void fuse_init_dir(struct inode *inode)
 
 static int fuse_symlink_read_folio(struct file *null, struct folio *folio)
 {
-	int err = fuse_readlink_page(folio->mapping->host, folio);
+	int err = fuse_readlink_folio(folio->mapping->host, folio);
 
 	if (!err)
 		folio_mark_uptodate(folio);