Cygwin: pipes: call nt_create with handle references

...to avoid potential pointer mishandling.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This commit is contained in:
Corinna Vinschen 2021-09-03 10:57:21 +02:00
parent 8653eb1df3
commit ea9c0bbedc
1 changed files with 23 additions and 32 deletions

View File

@ -660,7 +660,7 @@ fhandler_pipe::create (LPSECURITY_ATTRIBUTES sa_ptr, PHANDLE r, PHANDLE w,
simplicity, nt_create will omit the 'open_mode' and 'name'
parameters, which aren't needed for our purposes. */
static int nt_create (LPSECURITY_ATTRIBUTES, PHANDLE, PHANDLE, DWORD,
static int nt_create (LPSECURITY_ATTRIBUTES, HANDLE &, HANDLE &, DWORD,
int64_t *);
int
@ -671,7 +671,7 @@ fhandler_pipe::create (fhandler_pipe *fhs[2], unsigned psize, int mode)
int res = -1;
int64_t unique_id;
int ret = nt_create (sa, &r, &w, psize, &unique_id);
int ret = nt_create (sa, r, w, psize, &unique_id);
if (ret)
__seterrno_from_win_error (ret);
else if ((fhs[0] = (fhandler_pipe *) build_fh_dev (*piper_dev)) == NULL)
@ -718,7 +718,7 @@ fhandler_pipe::create (fhandler_pipe *fhs[2], unsigned psize, int mode)
}
static int
nt_create (LPSECURITY_ATTRIBUTES sa_ptr, PHANDLE r, PHANDLE w,
nt_create (LPSECURITY_ATTRIBUTES sa_ptr, HANDLE &r, HANDLE &w,
DWORD psize, int64_t *unique_id)
{
NTSTATUS status;
@ -729,10 +729,8 @@ nt_create (LPSECURITY_ATTRIBUTES sa_ptr, PHANDLE r, PHANDLE w,
LARGE_INTEGER timeout;
/* Default to error. */
if (r)
*r = NULL;
if (w)
*w = NULL;
r = NULL;
w = NULL;
status = fhandler_base::npfs_handle (npfsh);
if (!NT_SUCCESS (status))
@ -760,7 +758,7 @@ nt_create (LPSECURITY_ATTRIBUTES sa_ptr, PHANDLE r, PHANDLE w,
Retrying will probably never be necessary, but we want
to be as robust as possible. */
DWORD err = 0;
while (r && !*r)
while (!r)
{
static volatile ULONG pipe_unique_id;
LONG id = InterlockedIncrement ((LONG *) &pipe_unique_id);
@ -779,7 +777,7 @@ nt_create (LPSECURITY_ATTRIBUTES sa_ptr, PHANDLE r, PHANDLE w,
npfsh, sa_ptr->lpSecurityDescriptor);
timeout.QuadPart = -500000;
status = NtCreateNamedPipeFile (r, access, &attr, &io,
status = NtCreateNamedPipeFile (&r, access, &attr, &io,
FILE_SHARE_READ | FILE_SHARE_WRITE,
FILE_CREATE, 0, pipe_type,
FILE_PIPE_BYTE_STREAM_MODE,
@ -787,7 +785,7 @@ nt_create (LPSECURITY_ATTRIBUTES sa_ptr, PHANDLE r, PHANDLE w,
if (NT_SUCCESS (status))
{
debug_printf ("pipe read handle %p", *r);
debug_printf ("pipe read handle %p", r);
err = 0;
break;
}
@ -800,49 +798,42 @@ nt_create (LPSECURITY_ATTRIBUTES sa_ptr, PHANDLE r, PHANDLE w,
/* The pipe is already open with compatible parameters.
Pick a new name and retry. */
debug_printf ("pipe busy, retrying");
*r = NULL;
r = NULL;
break;
case STATUS_ACCESS_DENIED:
/* The pipe is already open with incompatible parameters.
Pick a new name and retry. */
debug_printf ("pipe access denied, retrying");
*r = NULL;
r = NULL;
break;
default:
{
__seterrno_from_nt_status (status);
err = GetLastError ();
debug_printf ("failed, %E");
*r = INVALID_HANDLE_VALUE;
r = INVALID_HANDLE_VALUE;
}
}
}
if (err)
{
*r = NULL;
r = NULL;
return err;
}
if (!w)
debug_printf ("pipe write handle NULL");
else
debug_printf ("NtOpenFile: name %S", &pipename);
access = GENERIC_WRITE | FILE_READ_ATTRIBUTES | SYNCHRONIZE;
status = NtOpenFile (&w, access, &attr, &io, 0, 0);
if (!NT_SUCCESS (status))
{
debug_printf ("NtOpenFile: name %S", &pipename);
access = GENERIC_WRITE | FILE_READ_ATTRIBUTES | SYNCHRONIZE;
status = NtOpenFile (w, access, &attr, &io, 0, 0);
if (!NT_SUCCESS (status))
{
DWORD err = GetLastError ();
debug_printf ("NtOpenFile failed, r %p, %E", r);
if (r)
NtClose (*r);
*w = NULL;
return err;
}
debug_printf ("pipe write handle %p", *w);
DWORD err = GetLastError ();
debug_printf ("NtOpenFile failed, r %p, %E", r);
if (r)
NtClose (r);
w = NULL;
return err;
}
/* Success. */