Cygwin: respect PC_SYM_FOLLOW and PC_SYM_NOFOLLOW_REP with inner links.

The new GetFinalPathNameW handling for native symlinks in inner path
components is disabled if caller doesn't want to follow symlinks, or
doesn't want to follow reparse points.
This commit is contained in:
Jeremy Drake 2021-05-29 11:48:11 -07:00 committed by Corinna Vinschen
parent d0e42141b8
commit 4fca7b0da6
1 changed files with 41 additions and 39 deletions

View File

@ -722,9 +722,10 @@ path_conv::check (const char *src, unsigned opt,
int symlen = 0;
/* Make sure to check certain flags on last component only. */
for (unsigned pc_flags = opt & (PC_NO_ACCESS_CHECK | PC_KEEP_HANDLE);
for (unsigned pc_flags = opt & (PC_NO_ACCESS_CHECK | PC_KEEP_HANDLE
| PC_SYM_FOLLOW | PC_SYM_NOFOLLOW_REP);
;
pc_flags = 0)
pc_flags = opt & (PC_SYM_FOLLOW | PC_SYM_NOFOLLOW_REP))
{
const suffix_info *suff;
char *full_path;
@ -3480,48 +3481,49 @@ restart:
goto file_not_symlink;
}
#endif /* __i386__ */
{
PWCHAR fpbuf = tp.w_get ();
DWORD ret;
if ((pc_flags & (PC_SYM_FOLLOW | PC_SYM_NOFOLLOW_REP)) == PC_SYM_FOLLOW)
{
PWCHAR fpbuf = tp.w_get ();
DWORD ret;
ret = GetFinalPathNameByHandleW (h, fpbuf, NT_MAX_PATH, 0);
if (ret)
{
UNICODE_STRING fpath;
ret = GetFinalPathNameByHandleW (h, fpbuf, NT_MAX_PATH, 0);
if (ret)
{
UNICODE_STRING fpath;
RtlInitCountedUnicodeString (&fpath, fpbuf, ret * sizeof (WCHAR));
fpbuf[1] = L'?'; /* \\?\ --> \??\ */
if (!RtlEqualUnicodeString (&upath, &fpath, !!ci_flag))
{
issymlink = true;
/* upath.Buffer is big enough and unused from this point on.
Reuse it here, avoiding yet another buffer allocation. */
char *nfpath = (char *) upath.Buffer;
sys_wcstombs (nfpath, NT_MAX_PATH, fpbuf);
res = posixify (nfpath);
RtlInitCountedUnicodeString (&fpath, fpbuf, ret * sizeof (WCHAR));
fpbuf[1] = L'?'; /* \\?\ --> \??\ */
if (!RtlEqualUnicodeString (&upath, &fpath, !!ci_flag))
{
issymlink = true;
/* upath.Buffer is big enough and unused from this point on.
Reuse it here, avoiding yet another buffer allocation. */
char *nfpath = (char *) upath.Buffer;
sys_wcstombs (nfpath, NT_MAX_PATH, fpbuf);
res = posixify (nfpath);
/* If the incoming path consisted of a drive prefix only,
we just handle a virtual drive, created with, e.g.
/* If the incoming path consisted of a drive prefix only,
we just handle a virtual drive, created with, e.g.
subst X: C:\foo\bar
subst X: C:\foo\bar
Treat it like a symlink. This is required to tell an
lstat caller that the "drive" is actually pointing
somewhere else, thus, it's a symlink in POSIX speak. */
if (upath.Length == 14) /* \??\X:\ */
{
fileattr &= ~FILE_ATTRIBUTE_DIRECTORY;
path_flags |= PATH_SYMLINK;
}
/* For final paths differing in inner path components return
length as negative value. This informs path_conv::check
to skip realpath handling on the last path component. */
else
res = -res;
break;
}
}
}
Treat it like a symlink. This is required to tell an
lstat caller that the "drive" is actually pointing
somewhere else, thus, it's a symlink in POSIX speak. */
if (upath.Length == 14) /* \??\X:\ */
{
fileattr &= ~FILE_ATTRIBUTE_DIRECTORY;
path_flags |= PATH_SYMLINK;
}
/* For final paths differing in inner path components return
length as negative value. This informs path_conv::check
to skip realpath handling on the last path component. */
else
res = -res;
break;
}
}
}
/* Normal file. */
file_not_symlink: