[Python-checkins] python/dist/src/Lib os.py,1.58,1.59
gvanrossum@users.sourceforge.net
gvanrossum@users.sourceforge.net
Mon, 05 Aug 2002 09:13:26 -0700
Update of /cvsroot/python/python/dist/src/Lib
In directory usw-pr-cvs1:/tmp/cvs-serv17001
Modified Files:
os.py
Log Message:
SF patch 590294: os._execvpe security fix (Zack Weinberg).
1) Do not attempt to exec a file which does not exist
just to find out what error the operating system
returns. This is an exploitable race on all platforms
that support symbolic links.
2) Immediately re-raise the exception if we get an
error other than errno.ENOENT or errno.ENOTDIR. This
may need to be adapted for other platforms.
(As a security issue, this should be considered for 2.1
and 2.2 as well as 2.3.)
Index: os.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/os.py,v
retrieving revision 1.58
retrieving revision 1.59
diff -C2 -d -r1.58 -r1.59
*** os.py 2 Jul 2002 21:28:04 -0000 1.58
--- os.py 5 Aug 2002 16:13:24 -0000 1.59
***************
*** 320,325 ****
__all__.extend(["execl","execle","execlp","execlpe","execvp","execvpe"])
- _notfound = None
def _execvpe(file, args, env=None):
if env is not None:
func = execve
--- 320,326 ----
__all__.extend(["execl","execle","execlp","execlpe","execvp","execvpe"])
def _execvpe(file, args, env=None):
+ from errno import ENOENT, ENOTDIR
+
if env is not None:
func = execve
***************
*** 329,333 ****
argrest = (args,)
env = environ
! global _notfound
head, tail = path.split(file)
if head:
--- 330,334 ----
argrest = (args,)
env = environ
!
head, tail = path.split(file)
if head:
***************
*** 339,357 ****
envpath = defpath
PATH = envpath.split(pathsep)
- if not _notfound:
- if sys.platform[:4] == 'beos':
- # Process handling (fork, wait) under BeOS (up to 5.0)
- # doesn't interoperate reliably with the thread interlocking
- # that happens during an import. The actual error we need
- # is the same on BeOS for posix.open() et al., ENOENT.
- try: unlink('/_#.# ## #.#')
- except error, _notfound: pass
- else:
- import tempfile
- t = tempfile.mktemp()
- # Exec a file that is guaranteed not to exist
- try: execv(t, ('blah',))
- except error, _notfound: pass
- exc, arg = error, _notfound
for dir in PATH:
fullname = path.join(dir, file)
--- 340,343 ----
***************
*** 359,366 ****
apply(func, (fullname,) + argrest)
except error, (errno, msg):
! if errno != arg[0]:
! exc, arg = error, (errno, msg)
! raise exc, arg
!
# Change environ to automatically call putenv() if it exists
--- 345,351 ----
apply(func, (fullname,) + argrest)
except error, (errno, msg):
! if errno != ENOENT and errno != ENOTDIR:
! raise
! raise error, (errno, msg)
# Change environ to automatically call putenv() if it exists