From cefd1b83275d4c587bdeb2fe7aed07908642f875 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Fri, 22 Oct 2021 17:03:02 +0200 Subject: fuse: decrement nlink on overwriting rename Rename didn't decrement/clear nlink on overwritten target inode. Create a common helper fuse_entry_unlinked() that handles this for unlink, rmdir and rename. Signed-off-by: Miklos Szeredi --- fs/fuse/dir.c | 49 +++++++++++++++++++++++++++---------------------- 1 file changed, 27 insertions(+), 22 deletions(-) (limited to 'fs/fuse') diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index 1b345ab48fd0..dd83b5d43fe5 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -755,6 +755,29 @@ void fuse_update_ctime(struct inode *inode) } } +static void fuse_entry_unlinked(struct dentry *entry) +{ + struct inode *inode = d_inode(entry); + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_inode *fi = get_fuse_inode(inode); + + spin_lock(&fi->lock); + fi->attr_version = atomic64_inc_return(&fc->attr_version); + /* + * If i_nlink == 0 then unlink doesn't make sense, yet this can + * happen if userspace filesystem is careless. It would be + * difficult to enforce correct nlink usage so just ignore this + * condition here + */ + if (S_ISDIR(inode->i_mode)) + clear_nlink(inode); + else if (inode->i_nlink > 0) + drop_nlink(inode); + spin_unlock(&fi->lock); + fuse_invalidate_entry_cache(entry); + fuse_update_ctime(inode); +} + static int fuse_unlink(struct inode *dir, struct dentry *entry) { int err; @@ -771,23 +794,8 @@ static int fuse_unlink(struct inode *dir, struct dentry *entry) args.in_args[0].value = entry->d_name.name; err = fuse_simple_request(fm, &args); if (!err) { - struct inode *inode = d_inode(entry); - struct fuse_inode *fi = get_fuse_inode(inode); - - spin_lock(&fi->lock); - fi->attr_version = atomic64_inc_return(&fm->fc->attr_version); - /* - * If i_nlink == 0 then unlink doesn't make sense, yet this can - * happen if userspace filesystem is careless. It would be - * difficult to enforce correct nlink usage so just ignore this - * condition here - */ - if (inode->i_nlink > 0) - drop_nlink(inode); - spin_unlock(&fi->lock); fuse_dir_changed(dir); - fuse_invalidate_entry_cache(entry); - fuse_update_ctime(inode); + fuse_entry_unlinked(entry); } else if (err == -EINTR) fuse_invalidate_entry(entry); return err; @@ -809,9 +817,8 @@ static int fuse_rmdir(struct inode *dir, struct dentry *entry) args.in_args[0].value = entry->d_name.name; err = fuse_simple_request(fm, &args); if (!err) { - clear_nlink(d_inode(entry)); fuse_dir_changed(dir); - fuse_invalidate_entry_cache(entry); + fuse_entry_unlinked(entry); } else if (err == -EINTR) fuse_invalidate_entry(entry); return err; @@ -851,10 +858,8 @@ static int fuse_rename_common(struct inode *olddir, struct dentry *oldent, fuse_dir_changed(newdir); /* newent will end up negative */ - if (!(flags & RENAME_EXCHANGE) && d_really_is_positive(newent)) { - fuse_invalidate_entry_cache(newent); - fuse_update_ctime(d_inode(newent)); - } + if (!(flags & RENAME_EXCHANGE) && d_really_is_positive(newent)) + fuse_entry_unlinked(newent); } else if (err == -EINTR) { /* If request was interrupted, DEITY only knows if the rename actually took place. If the invalidation -- cgit v1.2.3