From 3f7920b36da0ae536040bdab88b8671f6bdf91d0 Mon Sep 17 00:00:00 2001 From: Konstantin Komarov Date: Fri, 24 Nov 2023 11:17:07 +0300 Subject: [PATCH] fs/ntfs3: Modified fix directory element type detection [ Upstream commit 22457c047ed971f2f2e33be593ddfabd9639a409 ] Unfortunately reparse attribute is used for many purposes (several dozens). It is not possible here to know is this name symlink or not. To get exactly the type of name we should to open inode (read mft). getattr for opened file (fstat) correctly returns symlink. Signed-off-by: Konstantin Komarov Signed-off-by: Sasha Levin --- fs/ntfs3/dir.c | 30 +++++++++++++++++++++++++----- 1 file changed, 25 insertions(+), 5 deletions(-) diff --git a/fs/ntfs3/dir.c b/fs/ntfs3/dir.c index d4d9f4ffb6d9a..c2fb76bb28f47 100644 --- a/fs/ntfs3/dir.c +++ b/fs/ntfs3/dir.c @@ -309,11 +309,31 @@ static inline int ntfs_filldir(struct ntfs_sb_info *sbi, struct ntfs_inode *ni, return 0; } - /* NTFS: symlinks are "dir + reparse" or "file + reparse" */ - if (fname->dup.fa & FILE_ATTRIBUTE_REPARSE_POINT) - dt_type = DT_LNK; - else - dt_type = (fname->dup.fa & FILE_ATTRIBUTE_DIRECTORY) ? DT_DIR : DT_REG; + /* + * NTFS: symlinks are "dir + reparse" or "file + reparse" + * Unfortunately reparse attribute is used for many purposes (several dozens). + * It is not possible here to know is this name symlink or not. + * To get exactly the type of name we should to open inode (read mft). + * getattr for opened file (fstat) correctly returns symlink. + */ + dt_type = (fname->dup.fa & FILE_ATTRIBUTE_DIRECTORY) ? DT_DIR : DT_REG; + + /* + * It is not reliable to detect the type of name using duplicated information + * stored in parent directory. + * The only correct way to get the type of name - read MFT record and find ATTR_STD. + * The code below is not good idea. + * It does additional locks/reads just to get the type of name. + * Should we use additional mount option to enable branch below? + */ + if ((fname->dup.fa & FILE_ATTRIBUTE_REPARSE_POINT) && + ino != ni->mi.rno) { + struct inode *inode = ntfs_iget5(sbi->sb, &e->ref, NULL); + if (!IS_ERR_OR_NULL(inode)) { + dt_type = fs_umode_to_dtype(inode->i_mode); + iput(inode); + } + } return !dir_emit(ctx, (s8 *)name, name_len, ino, dt_type); } -- 2.47.3