The `FOLLOW_SYMLINKS` flag was added to the dir-iterator API in
fa1da7d2ee (dir-iterator: add flags parameter to dir_iterator_begin,
2019-07-10) in order to follow symbolic links while traversing through a
directory.
`FOLLOW_SYMLINKS` gained its first caller in ff7ccc8c9a (clone: use
dir-iterator to avoid explicit dir traversal, 2019-07-10), but it was
subsequently removed in 6f054f9fb3 (builtin/clone.c: disallow `--local`
clones with symlinks, 2022-07-28).
Since then, we've held on to the code for `DIR_ITERATOR_FOLLOW_SYMLINKS`
in the name of making minimally invasive changes during a security
embargo.
In fact, we even changed the dir-iterator API in bffc762f87
(dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS,
2023-01-24) without having any non-test callers of that flag.
Now that we're past those security embargo(s), let's finalize our
cleanup of the `DIR_ITERATOR_FOLLOW_SYMLINKS` code and remove its
implementation since there are no remaining callers.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When using the dir_iterator API, we first stat(2) the base path, and
then use that as a starting point to enumerate the directory's contents.
If the directory contains symbolic links, we will immediately die() upon
encountering them without the `FOLLOW_SYMLINKS` flag. The same is not
true when resolving the top-level directory, though.
As explained in a previous commit, this oversight in 6f054f9fb3
(builtin/clone.c: disallow `--local` clones with symlinks, 2022-07-28)
can be used as an attack vector to include arbitrary files on a victim's
filesystem from outside of the repository.
Prevent resolving top-level symlinks unless the FOLLOW_SYMLINKS flag is
given, which will cause clones of a repository with a symlink'd
"$GIT_DIR/objects" directory to fail.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add the possibility of giving flags to dir_iterator_begin to initialize
a dir-iterator with special options.
Currently possible flags are:
- DIR_ITERATOR_PEDANTIC, which makes dir_iterator_advance abort
immediately in the case of an error, instead of keep looking for the
next valid entry;
- DIR_ITERATOR_FOLLOW_SYMLINKS, which makes the iterator follow
symlinks and include linked directories' contents in the iteration.
These new flags will be used in a subsequent patch.
Also add tests for the flags' usage and adjust refs/files-backend.c to
the new dir_iterator_begin signature.
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
dir_iterator_advance() is a large function with two nested loops. Let's
improve its readability factoring out three functions and simplifying
its mechanics. The refactored model will no longer depend on
level.initialized and level.dir_state to keep track of the iteration
state and will perform on a single loop.
Also, dir_iterator_begin() currently does not check if the given string
represents a valid directory path. Since the refactored model will have
to stat() the given path at initialization, let's also check for this
kind of error and make dir_iterator_begin() return NULL, on failures,
with errno appropriately set. And add tests for this new behavior.
Improve documentation at dir-iteration.h and code comments at
dir-iterator.c to reflect the changes and eliminate possible
ambiguities.
Finally, adjust refs/files-backend.c to check for now possible
dir_iterator_begin() failures.
Original-patch-by: Daniel Ferreira <bnmvco@gmail.com>
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
I looped over the toplevel header files, creating a temporary two-line C
program for each consisting of
#include "git-compat-util.h"
#include $HEADER
This patch is the result of manually fixing errors in compiling those
tiny programs.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The iterator interface is modeled on that for references, though no
vtable is necessary because there is (so far?) only one type of
dir_iterator.
There are obviously a lot of features that could easily be added to this
class:
* Skip/include directory paths in the iteration
* Shallow/deep iteration
* Letting the caller decide which subdirectories to recurse into (e.g.,
via a dir_iterator_advance_into() function)
* Option to iterate in sorted order
* Option to iterate over directory paths before vs. after their contents
But these are not needed for the current patch series, so I refrain.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
