sys/linux: fix up mptcp descriptions

1. Generate .const files for all arches.
2. Don't extract mptcp consts on android.
3. Remove mptcp includes from vnet.txt.
4. Enable CONFIG_MPTCP in syz-extract (mptcp is not like all other kernel headers).

2 files changed, 14 insertions, 5 deletions

diff --git a/sys/syz-extract/extract.go b/sys/syz-extract/extract.go
index fe32bc429..29ef66196 100644
--- a/sys/syz-extract/extract.go
+++ b/sys/syz-extract/extract.go
@@ -21,7 +21,7 @@ import (
 )
 
 var (
-	flagOS        = flag.String("os", "", "target OS")
+	flagOS        = flag.String("os", runtime.GOOS, "target OS")
 	flagBuild     = flag.Bool("build", false, "regenerate arch-specific kernel headers")
 	flagSourceDir = flag.String("sourcedir", "", "path to kernel source checkout dir")
 	flagIncludes  = flag.String("includedirs", "", "path to other kernel source include dirs separated by commas")
@@ -245,16 +245,19 @@ func archFileList(os, arch string, files []string) (string, []string, []string,
 		if err != nil || len(matches) == 0 {
 			return "", nil, nil, fmt.Errorf("failed to find sys files: %v", err)
 		}
+		manualFiles := map[string]bool{
+			// Not upstream, generated on https://github.com/multipath-tcp/mptcp_net-next
+			"mptcp.txt": true,
+		}
 		androidFiles := map[string]bool{
 			"tlk_device.txt": true,
 			// This was generated on:
 			// https://source.codeaurora.org/quic/la/kernel/msm-4.9 msm-4.9
 			"video4linux.txt": true,
-			"mptcp.txt":       true,
 		}
 		for _, f := range matches {
 			f = filepath.Base(f)
-			if os == "linux" && android != androidFiles[f] {
+			if manualFiles[f] || os == "linux" && android != androidFiles[f] {
 				continue
 			}
 			files = append(files, f)
diff --git a/sys/syz-extract/linux.go b/sys/syz-extract/linux.go
index 6cfc18419..45f8144ce 100644
--- a/sys/syz-extract/linux.go
+++ b/sys/syz-extract/linux.go
@@ -83,10 +83,16 @@ func (*linux) prepareArch(arch *Arch) error {
 		return fmt.Errorf("make defconfig failed: %v\n%s", err, out)
 	}
 	// Without CONFIG_NETFILTER kernel does not build.
-	out, err = osutil.RunCmd(time.Minute, buildDir, "sed", "-i",
+	_, err = osutil.RunCmd(time.Minute, buildDir, "sed", "-i",
 		"s@# CONFIG_NETFILTER is not set@CONFIG_NETFILTER=y@g", ".config")
 	if err != nil {
-		return fmt.Errorf("sed .config failed: %v\n%s", err, out)
+		return fmt.Errorf("sed .config failed: %v", err)
+	}
+	// include/net/mptcp.h is the only header in kernel that guards some of the consts with own config
+	_, err = osutil.RunCmd(time.Minute, buildDir, "sed", "-i",
+		"s@# CONFIG_MPTCP is not set@CONFIG_MPTCP=y@g", ".config")
+	if err != nil {
+		return fmt.Errorf("sed .config failed: %v", err)
 	}
 	out, err = osutil.RunCmd(time.Hour, kernelDir, "make", append(makeArgs, "olddefconfig")...)
 	if err != nil {