tree 4b143b84ee9ad075e6342094ee262e7dcc748a42
parent 243c8eb8c290ebbf2e2811da2dd7538200dde6b3
author Jason A. Donenfeld <Jason@zx2c4.com> 1551896789 +0100
committer Alex Brainman <alex.brainman@gmail.com> 1552196413 +0000

runtime: safely load DLLs

While many other call sites have been moved to using the proper
higher-level system loading, these areas were left out. This prevents
DLL directory injection attacks. This includes both the runtime load
calls (using LoadLibrary prior) and the implicitly linked ones via
cgo_import_dynamic, which we move to our LoadLibraryEx. The goal is to
only loosely load kernel32.dll and strictly load all others.

Meanwhile we make sure that we never fallback to insecure loading on
older or unpatched systems.

This is CVE-2019-9634.

Fixes #14959
Fixes #28978
Fixes #30642

Change-Id: I401a13ed8db248ab1bb5039bf2d31915cac72b93
Reviewed-on: https://go-review.googlesource.com/c/go/+/165798
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>