windows: allocate SECURITY_DESCRIPTOR with uintptr alignment
This struct has pointers in it, which means checkptr expects for it to
be aligned properly. When we're copying a Windows-allocated struct to a
Go-allocated one, make sure that the Go allocation is aligned to the
pointer size.
This fixes the following checkptr splat:
goroutine 29 [running]:
runtime.throw(0x4f8dd9, 0x3a)
C:/hostedtoolcache/windows/go/1.16.2/x64/src/runtime/panic.go:1117 +0x79 fp=0xc000041c50 sp=0xc000041c20 pc=0x2f9879
runtime.checkptrAlignment(0xc00009c180, 0x4d8a00, 0x1)
C:/hostedtoolcache/windows/go/1.16.2/x64/src/runtime/checkptr.go:20 +0xc9 fp=0xc000041c80 sp=0xc000041c50 pc=0x2c4d09
golang.org/x/sys/windows.(*SECURITY_DESCRIPTOR).copySelfRelativeSecurityDescriptor(0x227284caa00, 0x2)
C:/Users/runneradmin/go/pkg/mod/golang.org/x/sys@v0.0.0-20210309040221-94ec62e08169/windows/security_windows.go:1347 +0x11f fp=0xc000041ce8 sp=0xc000041c80 pc=0x467f9f
golang.org/x/sys/windows.SecurityDescriptorFromString(0x4ebfb0, 0x2, 0x0, 0x0, 0x0)
Change-Id: I7eb9c07e7afb7f139473b660f82a23541663ec50
Reviewed-on: https://go-review.googlesource.com/c/sys/+/306889
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
diff --git a/windows/security_windows.go b/windows/security_windows.go
index 0e428ec..dd68372 100644
--- a/windows/security_windows.go
+++ b/windows/security_windows.go
@@ -1342,7 +1342,15 @@
h.Len = sdLen
h.Cap = sdLen
- dst := make([]byte, sdLen)
+ const psize = int(unsafe.Sizeof(uintptr(0)))
+
+ var dst []byte
+ h = (*unsafeheader.Slice)(unsafe.Pointer(&dst))
+ alloc := make([]uintptr, (sdLen+psize-1)/psize)
+ h.Data = (*unsafeheader.Slice)(unsafe.Pointer(&alloc)).Data
+ h.Len = sdLen
+ h.Cap = sdLen
+
copy(dst, src)
return (*SECURITY_DESCRIPTOR)(unsafe.Pointer(&dst[0]))
}
