From: Lucas Zamboni Orioli via GitGitGadget Date: Thu, 30 Jul 2026 11:28:02 GMT Subject: [PATCH v5 0/2] mv: report missing destination leading directory Message-ID: In-Reply-To: Changes in v5: * extracted the shared "will this move rename on disk?" condition into a needs_worktree_rename() helper used by both the new leading-directory check and the actual rename(), so the two cannot drift, per Junio C Hamano * allocate the dirname copy only when the destination has a slash * reworded the opening of the commit message for clarity, per Junio C Hamano * added tests: moving into an existing directory (destination is normalized to a full path), and moving to a bare filename in the cwd (no leading directory to check) Changes in v4: * reverted to lstat and added has_symlink_leading_path() to refuse a destination that goes through a symbolic link, independent of the link target, per Junio C Hamano's point that Git tracks symlinks and must not follow them here * added new "destination is beyond a symbolic link" message * added tests: symlink as immediate parent and as intermediate component, symlink at the destination, -f does not bypass the symlink refusal, and a regression test that a move through a symlink no longer corrupts the index (see the reproduction reported on the list) Changes in v3: * added ENOTDIR handling and an S_ISDIR check so a non-directory leading path component is caught, as suggested by Junio C Hamano * (v3 used stat() to resolve symlinks; this was reverted in v4 after Junio pointed out symlinks must not be followed) * fixed indentation Changes in v2: * altered the error message to include both source and destination as suggested by Ben Knoble Lucas Zamboni Orioli (2): mv: name both source and destination when rename fails mv: reject a destination whose leading path is missing or a symlink builtin/mv.c | 47 +++++++++++++++++++++-- t/t7001-mv.sh | 102 ++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 146 insertions(+), 3 deletions(-) base-commit: 9a0c4701dcd5725c4184599322b52933ff5005ca Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-2356%2FZamboniL%2Fmv-detect-non-existing-target-folder-v5 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-2356/ZamboniL/mv-detect-non-existing-target-folder-v5 Pull-Request: https://github.com/git/git/pull/2356 Range-diff vs v4: 1: 0d67da588b = 1: 0d67da588b mv: name both source and destination when rename fails 2: 6b72efb413 ! 2: 6c2909e609 mv: reject a destination whose leading path is missing or a symlink @@ Metadata ## Commit message ## mv: reject a destination whose leading path is missing or a symlink - Moving a file into a destination whose leading directories are not all - present, real directories is only diagnosed later at rename(2), and for - a symlinked component is not diagnosed at all. + When moving a file, if any leading directory in the destination path + is missing or is not a real directory, the problem is detected only + later when rename() is called. Furthermore, if a leading directory + component is a symbolic link, the issue is not detected at all. Three cases reach rename(2) unchecked today: @@ builtin/mv.c #include "setup.h" #include "strvec.h" +@@ builtin/mv.c: enum update_mode { + MOVE_VIA_PARENT_DIR = (1 << 5), + }; + ++static int needs_worktree_rename(enum update_mode mode, enum update_mode dst_mode) ++{ ++ return !(mode & (INDEX | SPARSE | SKIP_WORKTREE_DIR)) && ++ !(dst_mode & (SKIP_WORKTREE_DIR | SPARSE)); ++} ++ + #define DUP_BASENAME 1 + #define KEEP_TRAILING_SLASH 2 + @@ builtin/mv.c: dir_check: bad = _("destination directory does not exist"); goto act_on_entry; @@ builtin/mv.c: dir_check: + * If we are going to move SRC to DST on disk, DST's leading + * directories must already exist. + */ -+ if (!(modes[i] & (INDEX | SPARSE | SKIP_WORKTREE_DIR)) && -+ !(dst_mode & (SKIP_WORKTREE_DIR | SPARSE))) { -+ char *dst_dir = xstrdup(dst); -+ char *slash = strrchr(dst_dir, '/'); ++ if (needs_worktree_rename(modes[i], dst_mode)) { ++ const char *slash_ = strrchr(dst, '/'); + -+ if (slash) { ++ if (slash_) { + struct stat dir_st; ++ char *dst_dir = xstrdup(dst); ++ char *slash = &dst_dir[slash_ - dst]; + + *slash = '\0'; + if (lstat(dst_dir, &dir_st) < 0) { @@ builtin/mv.c: dir_check: + } else if (!S_ISDIR(dir_st.st_mode)) { + bad = _("destination is not a directory"); + } ++ ++ free(dst_dir); + } -+ free(dst_dir); + + if (bad) + goto act_on_entry; @@ builtin/mv.c: dir_check: if (ignore_sparse && (dst_mode & (SKIP_WORKTREE_DIR | SPARSE)) && +@@ builtin/mv.c: remove_entry: + printf(_("Renaming %s to %s\n"), src, dst); + if (show_only) + continue; +- if (!(mode & (INDEX | SPARSE | SKIP_WORKTREE_DIR)) && +- !(dst_mode & (SKIP_WORKTREE_DIR | SPARSE)) && ++ if (needs_worktree_rename(mode, dst_mode) && + rename(src, dst) < 0) { + if (ignore_errors) + continue; ## t/t7001-mv.sh ## @@ t/t7001-mv.sh: test_expect_success 'clean up' ' git reset --hard ' ++test_expect_success 'moving file to directory without trailing slash' ' ++ git reset --hard HEAD && ++ rm -rf file.txt target && mkdir target && ++ echo content > file.txt && ++ git add file.txt && ++ git mv file.txt target && ++ test_path_is_file target/file.txt ++' ++ ++test_expect_success 'moving file to a bare filename in the cwd' ' ++ git reset --hard && ++ rm -rf from dest.txt && ++ mkdir from && ++ echo content >from/file && ++ git add from/file && ++ git mv from/file dest.txt && ++ test_path_is_file dest.txt ++' ++ +test_expect_success 'moving to a non-existent directory' ' + git reset --hard && + rm -rf from && mkdir from && -- gitgitgadget