The existing code errors as EINVAL any attempt to set a value for
SO_PEERCRED via setsockopt() on an AF_UNIX/AF_LOCAL socket. But to
enable the workaround set_no_getpeereid behavior for Python one has
to be able to set SO_PEERCRED to zero. Ergo, this patch. Python has
no way to specify a NULL pointer for 'optval'.
This v2 of patch allows the original working (i.e., allow NULL,0 for
optval,optlen to mean turn off SO_PEERCRED) in addition to the new
working described above. The sense of the 'if' stmt is reversed for
readability.
---
winsup/cygwin/fhandler_socket_local.cc | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/winsup/cygwin/fhandler_socket_local.cc
b/winsup/cygwin/fhandler_socket_local.cc
index c94bf828f..964f3e819 100644
--- a/winsup/cygwin/fhandler_socket_local.cc
+++ b/winsup/cygwin/fhandler_socket_local.cc
@@ -1430,10 +1430,14 @@ fhandler_socket_local::setsockopt (int level, int
optname, const void *optval,
FIXME: In the long run we should find a more generic solution
which doesn't require a blocking handshake in accept/connect
to exchange SO_PEERCRED credentials. */
- if (optval || optlen)
- set_errno (EINVAL);
- else
+ /* Temporary: Allow SO_PEERCRED to only be zeroed. Two ways to
+ accomplish this: pass NULL,0 for optval,optlen; or pass the
+ address,length of an '(int) 0' set up by the caller. */
+ if ((!optval && !optlen) ||
+ (optlen == (socklen_t) sizeof (int) && !*(int *) optval))
ret = af_local_set_no_getpeereid ();
+ else
+ set_errno (EINVAL);
return ret;
case SO_REUSEADDR:
--
2.29.2
