From: Jason A. Donenfeld <Jason@zx2c4.com>
Date: Thu, 25 Feb 2021 01:58:04 +0000 (+0100)
Subject: syscall: return error if GetQueuedCompletionStatus truncates key
X-Git-Tag: go1.17beta1~1374
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=37ca84a9cd;p=gostls13.git

syscall: return error if GetQueuedCompletionStatus truncates key

This function has the wrong signature, so return an error when that
actually might lead to unexpected results. Users should switch to
x/sys/windows for the real version of this function.

Updates #44538.

Change-Id: I4d1f3d1e380815733ecfea683f939b1d25dcc32a
Reviewed-on: https://go-review.googlesource.com/c/go/+/296154
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
---

diff --git a/src/syscall/syscall_windows.go b/src/syscall/syscall_windows.go
index 5310f2da80..ee5311b176 100644
--- a/src/syscall/syscall_windows.go
+++ b/src/syscall/syscall_windows.go
@@ -1229,6 +1229,9 @@ func GetQueuedCompletionStatus(cphandle Handle, qty *uint32, key *uint32, overla
 	err := getQueuedCompletionStatus(cphandle, qty, pukey, overlapped, timeout)
 	if key != nil {
 		*key = uint32(ukey)
+		if uintptr(*key) != ukey && err == nil {
+			err = errorspkg.New("GetQueuedCompletionStatus returned key overflow")
+		}
 	}
 	return err
 }