From: Ken Brown <kbrown@cornell.edu>
To: cygwin-devel <cygwin-developers@cygwin.com>
Subject: Potential handle leaks in dup_worker
Date: Mon, 8 Feb 2021 12:39:26 -0500 [thread overview]
Message-ID: <2fef1107-005d-9a44-fd4a-79fa5904d436@cornell.edu> (raw)
I've had occasion to work through dtable::dup_worker, and I'm seeing the
potential for leaks of path_conv handles. I haven't seen any evidence that the
leaks actually occur, but the code should probably be cleaned up if I'm right.
dup_worker calls clone to create newfh from oldfh. clone calls copyto, which
calls operator=, which calls path_conv::operator=, which duplicates the
path_conv handle from oldfh to newfh. Then copyto calls reset, which calls
path_conv::operator<<, which again duplicates the path_conv handle from oldfh to
newfh without first closing the previous one. That's the first leak.
Further on, dup_worker calls newfh->pc.reset_conv_handle (), which sets the
path_conv handle of newfh to NULL without closing the existing handle. So
that's a second leak. This one is easily fixed by calling close_conv_handle
instead of reset_conv_handle.
As a practical matter, I think the path_conv handle of oldfh is always NULL when
dup_worker is called, so there's no actual leak.
I may well be confused and/or missing something.
Ken
next reply other threads:[~2021-02-08 17:39 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-08 17:39 Ken Brown [this message]
2021-02-09 9:47 ` Corinna Vinschen
2021-02-09 14:19 ` Ken Brown
2021-02-09 15:02 ` Corinna Vinschen
2021-02-09 15:04 ` Corinna Vinschen
2021-02-09 15:31 ` Ken Brown
2021-02-09 16:12 ` Corinna Vinschen
2021-02-09 17:13 ` Ken Brown
2021-02-09 19:12 ` Ken Brown
2021-02-09 20:52 ` Corinna Vinschen
2021-02-09 22:31 ` Ken Brown
2021-02-10 9:52 ` Corinna Vinschen
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