Junio C Hamano <gits...@pobox.com> writes:

> Michael Haggerty <mhag...@alum.mit.edu> writes:
>
>> When reading a symbolic ref via resolve_gitlink_ref_recursive(), check
>> that the reference name that is pointed at is formatted correctly,
>> using the same check as resolve_ref_unsafe() uses for non-gitlink
>> references.  This prevents bogosity like
>>
>>     ref: ../../other/file
>>
>> from causing problems.
>
> I do agree that a textual symref "ref: ../../x/y" that is stored in
> ".git/HEAD" or in ".git/refs/L" will step outside ".git/" and it is
> problematic.  But if ".git/refs/heads/a/b/LINK" has "ref: ../../x"
> in it, shouldn't we interpret it as referring to the ref at
> "refs/heads/x"?

Actually, the textual symrefs have been invented to replace symbolic
links used for .git/HEAD on symlink-incapable filesystems, and we do
even not let the filesystem follow symlinks.  The rule we have there
are like so:

                /* Follow "normalized" - ie "refs/.." symlinks by hand */
                if (S_ISLNK(st.st_mode)) {
                        len = readlink(path, buffer, sizeof(buffer)-1);
                        if (len < 0) {
                                if (errno == ENOENT || errno == EINVAL)
                                        /* inconsistent with lstat; retry */
                                        goto stat_ref;
                                else
                                        return NULL;
                        }
                        buffer[len] = 0;
                        if (starts_with(buffer, "refs/") &&
                                        !check_refname_format(buffer, 0)) {
                                strcpy(refname_buffer, buffer);
                                refname = refname_buffer;
                                if (flag)
                                        *flag |= REF_ISSYMREF;
                                continue;
                        }
                }

So we should do exactly the same check, I would think, no?

In a typical clone, the ".git/refs/remotes/origin/HEAD" textual
symref stores "ref: refs/remotes/origin/master" and it is neither
"ref: master" nor "ref: ./master", so it should be sensible to
insist on "must start with 'refs/' and its format valid."


--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to