From: Alex Richardson <Alexander.Richardson@cl.cam.ac.uk>
Date: Thu, 17 Sep 2020 17:14:58 +0000 (+0100)
Subject: Avoid mismatch between library and test crypto configuration
X-Git-Tag: v3.5.0~15^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0d8b61ea93fb1cd54d30d21823b0bc4d15347f2a;p=thirdparty%2Flibarchive.git

Avoid mismatch between library and test crypto configuration

I was investigating libarchive test failures on FreeBSD and it turns out
we get a reproducible SIGBUS for test_archive_m5, etc. Debugging this shows
that libarchive and the tests disagree when it comes to the definition of
archive_md5_ctx: libarchive assumes it's the OpenSSL type whereas the test
use the libmd type. The latter is not necessarily aligned enough to store
a pointer (16 bytes for CHERI RISC-V), so we were crashing when storing
EVP_MD_CTX* to an 8-byte-aligned archive_md5_ctx.

To avoid problems like this in the future, add a new macro to the config
header and use that to ensure that all configuration check macros have
been defined in archive_digest_private.h.
---

diff --git a/build/cmake/config.h.in b/build/cmake/config.h.in
index fcbd80c5a..6d2fa7469 100644
--- a/build/cmake/config.h.in
+++ b/build/cmake/config.h.in
@@ -1,4 +1,5 @@
 /* config.h.  Generated from build/cmake/config.h.in by cmake configure */
+#define __LIBARCHIVE_CONFIG_H_INCLUDED 1
 
 /*
  * Ensure we have C99-style int64_t, etc, all defined.
diff --git a/configure.ac b/configure.ac
index fbb7b3c25..65c889a2f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -47,6 +47,8 @@ ARCHIVE_REVISION=$(( LIBARCHIVE_VERSION_N() % 1000 ))
 ARCHIVE_LIBTOOL_VERSION=$ARCHIVE_INTERFACE:$ARCHIVE_REVISION:$ARCHIVE_MINOR
 
 # Stick the version numbers into config.h
+AC_DEFINE([__LIBARCHIVE_CONFIG_H_INCLUDED], [1],
+	[Internal macro for sanity checks])
 AC_DEFINE([LIBARCHIVE_VERSION_STRING],"LIBARCHIVE_VERSION_S()",
 	[Version number of libarchive])
 AC_DEFINE_UNQUOTED([LIBARCHIVE_VERSION_NUMBER],"LIBARCHIVE_VERSION_N()",
diff --git a/libarchive/archive_digest_private.h b/libarchive/archive_digest_private.h
index 15312ee9a..9b3bd6621 100644
--- a/libarchive/archive_digest_private.h
+++ b/libarchive/archive_digest_private.h
@@ -30,6 +30,10 @@
 #ifndef __LIBARCHIVE_BUILD
 #error This header is only to be used internally to libarchive.
 #endif
+#ifndef __LIBARCHIVE_CONFIG_H_INCLUDED
+#error "Should have include config.h first!"
+#endif
+
 /*
  * Crypto support in various Operating Systems:
  *
diff --git a/libarchive/config_freebsd.h b/libarchive/config_freebsd.h
index f16fd3495..a05121c78 100644
--- a/libarchive/config_freebsd.h
+++ b/libarchive/config_freebsd.h
@@ -24,6 +24,7 @@
  *
  * $FreeBSD$
  */
+#define __LIBARCHIVE_CONFIG_H_INCLUDED 1
 
 #include <osreldate.h>