pkg/csource: support akaros

1 files changed, 154 insertions, 122 deletions

diff --git a/pkg/csource/csource.go b/pkg/csource/csource.go
index b0d44a94f..1bc1ec5ba 100644
--- a/pkg/csource/csource.go
+++ b/pkg/csource/csource.go
@@ -1,17 +1,13 @@
 // Copyright 2015 syzkaller project authors. All rights reserved.
 // Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
 
-// I heard you like shell...
-//go:generate bash -c "echo -e '// AUTOGENERATED FROM executor/common_linux.h\npackage csource\nvar commonHeader = `' > common.go; cat ../../executor/common_linux.h | sed -e '/#include \"common.h\"/ {' -e 'r ../../executor/common.h' -e 'd' -e '}' - | sed -e '/#include \"common_kvm_amd64.h\"/ {' -e 'r ../../executor/common_kvm_amd64.h' -e 'd' -e '}' - | sed -e '/#include \"common_kvm_arm64.h\"/ {' -e 'r ../../executor/common_kvm_arm64.h' -e 'd' -e '}' - | sed -e '/#include \"kvm.h\"/ {' -e 'r ../../executor/kvm.h' -e 'd' -e '}' - | sed -e '/#include \"kvm.S.h\"/ {' -e 'r ../../executor/kvm.S.h' -e 'd' -e '}' - | egrep -v '^[   ]*//' | sed '/^[ 	]*\\/\\/.*/d' | sed 's#[ 	]*//.*##g' >> common.go; echo '`' >> common.go"
-//go:generate go fmt common.go
-
+// Package csource generates [almost] equivalent C programs from syzkaller programs.
 package csource
 
 import (
 	"bytes"
 	"errors"
 	"fmt"
-	"io"
 	"io/ioutil"
 	"os"
 	"os/exec"
@@ -71,122 +67,119 @@ func Write(p *prog.Prog, opts Options) ([]byte, error) {
 	if err := opts.Check(); err != nil {
 		return nil, fmt.Errorf("csource: invalid opts: %v", err)
 	}
-	exec := make([]byte, prog.ExecBufferSize)
-	if _, err := p.SerializeForExec(exec, 0); err != nil {
-		return nil, fmt.Errorf("failed to serialize program: %v", err)
+	commonHeader := ""
+	switch p.Target.OS {
+	case "linux":
+		commonHeader = commonHeaderLinux
+	case "akaros":
+		commonHeader = commonHeaderAkaros
+	default:
+		return nil, fmt.Errorf("unsupported OS: %v", p.Target.OS)
+	}
+	ctx := &context{
+		p:         p,
+		opts:      opts,
+		target:    p.Target,
+		sysTarget: targets.List[p.Target.OS][p.Target.Arch],
+		w:         new(bytes.Buffer),
+		calls:     make(map[string]uint64),
 	}
-	w := new(bytes.Buffer)
-
-	fmt.Fprint(w, "// autogenerated by syzkaller (http://github.com/google/syzkaller)\n\n")
-
-	handled := make(map[string]uint64)
 	for _, c := range p.Calls {
-		handled[c.Meta.CallName] = c.Meta.NR
+		ctx.calls[c.Meta.CallName] = c.Meta.NR
 	}
-	hdr, err := preprocessCommonHeader(p.Target, opts, handled, prog.RequiresBitmasks(p), prog.RequiresChecksums(p))
+
+	ctx.print("// autogenerated by syzkaller (http://github.com/google/syzkaller)\n\n")
+
+	hdr, err := ctx.preprocessCommonHeader(commonHeader)
 	if err != nil {
 		return nil, err
 	}
-	fmt.Fprint(w, hdr)
-	fmt.Fprint(w, "\n")
+	ctx.print(hdr)
+	ctx.print("\n")
 
-	for name, nr := range handled {
-		if strings.HasPrefix(name, "syz_") {
-			continue
-		}
-		if p.Target.OS == "linux" && p.Target.Arch == "amd64" && nr < 313 {
-			// Only generate defines for new syscalls (added after commit 8a1ab3155c2ac on 2012-10-04).
-			continue
-		}
-		fmt.Fprintf(w, "#ifndef __NR_%v\n", name)
-		fmt.Fprintf(w, "#define __NR_%v %v\n", name, nr)
-		fmt.Fprintf(w, "#endif\n")
-	}
-	if p.Target.OS == "linux" && p.Target.PtrSize == 4 {
-		// This is a dirty hack.
-		// On 32-bit linux mmap translated to old_mmap syscall which has a different signature.
-		// mmap2 has the right signature. executor translates mmap to mmap2, do the same here.
-		fmt.Fprintf(w, "#undef __NR_mmap\n")
-		fmt.Fprintf(w, "#define __NR_mmap __NR_mmap2\n")
-	}
-	fmt.Fprintf(w, "\n")
+	ctx.generateSyscallDefines()
 
-	calls, nvar := generateCalls(p.Target, exec, opts)
-	fmt.Fprintf(w, "long r[%v];\n", nvar)
+	exec := make([]byte, prog.ExecBufferSize)
+	progSize, err := ctx.p.SerializeForExec(exec, 0)
+	if err != nil {
+		return nil, fmt.Errorf("failed to serialize program: %v", err)
+	}
+	calls, nvar := ctx.generateCalls(exec[:progSize])
+	ctx.printf("long r[%v];\n", nvar)
 
 	if !opts.Repeat {
-		generateTestFunc(w, opts, calls, "loop")
+		ctx.generateTestFunc(calls, "loop")
 
-		fmt.Fprint(w, "int main()\n{\n")
+		ctx.print("int main()\n{\n")
 		if opts.HandleSegv {
-			fmt.Fprintf(w, "\tinstall_segv_handler();\n")
+			ctx.printf("\tinstall_segv_handler();\n")
 		}
 		if opts.UseTmpDir {
-			fmt.Fprintf(w, "\tuse_temporary_dir();\n")
+			ctx.printf("\tuse_temporary_dir();\n")
 		}
 		if opts.Sandbox != "" {
-			fmt.Fprintf(w, "\tint pid = do_sandbox_%v(0, %v);\n", opts.Sandbox, opts.EnableTun)
-			fmt.Fprint(w, "\tint status = 0;\n")
-			fmt.Fprint(w, "\twhile (waitpid(pid, &status, __WALL) != pid) {}\n")
+			ctx.printf("\tint pid = do_sandbox_%v(0, %v);\n", opts.Sandbox, opts.EnableTun)
+			ctx.print("\tint status = 0;\n")
+			ctx.print("\twhile (waitpid(pid, &status, __WALL) != pid) {}\n")
 		} else {
 			if opts.EnableTun {
-				fmt.Fprintf(w, "\tsetup_tun(0, %v);\n", opts.EnableTun)
+				ctx.printf("\tsetup_tun(0, %v);\n", opts.EnableTun)
 			}
-			fmt.Fprint(w, "\tloop();\n")
+			ctx.print("\tloop();\n")
 		}
-		fmt.Fprint(w, "\treturn 0;\n}\n")
+		ctx.print("\treturn 0;\n}\n")
 	} else {
-		generateTestFunc(w, opts, calls, "test")
+		ctx.generateTestFunc(calls, "test")
 		if opts.Procs <= 1 {
-			fmt.Fprint(w, "int main()\n{\n")
+			ctx.print("int main()\n{\n")
 			if opts.HandleSegv {
-				fmt.Fprintf(w, "\tinstall_segv_handler();\n")
+				ctx.printf("\tinstall_segv_handler();\n")
 			}
 			if opts.UseTmpDir {
-				fmt.Fprintf(w, "\tuse_temporary_dir();\n")
+				ctx.printf("\tuse_temporary_dir();\n")
 			}
 			if opts.Sandbox != "" {
-				fmt.Fprintf(w, "\tint pid = do_sandbox_%v(0, %v);\n", opts.Sandbox, opts.EnableTun)
-				fmt.Fprint(w, "\tint status = 0;\n")
-				fmt.Fprint(w, "\twhile (waitpid(pid, &status, __WALL) != pid) {}\n")
+				ctx.printf("\tint pid = do_sandbox_%v(0, %v);\n", opts.Sandbox, opts.EnableTun)
+				ctx.print("\tint status = 0;\n")
+				ctx.print("\twhile (waitpid(pid, &status, __WALL) != pid) {}\n")
 			} else {
 				if opts.EnableTun {
-					fmt.Fprintf(w, "\tsetup_tun(0, %v);\n", opts.EnableTun)
+					ctx.printf("\tsetup_tun(0, %v);\n", opts.EnableTun)
 				}
-				fmt.Fprint(w, "\tloop();\n")
+				ctx.print("\tloop();\n")
 			}
-			fmt.Fprint(w, "\treturn 0;\n}\n")
+			ctx.print("\treturn 0;\n}\n")
 		} else {
-			fmt.Fprint(w, "int main()\n{\n")
-			fmt.Fprint(w, "\tint i;")
-			fmt.Fprintf(w, "\tfor (i = 0; i < %v; i++) {\n", opts.Procs)
-			fmt.Fprint(w, "\t\tif (fork() == 0) {\n")
+			ctx.print("int main()\n{\n")
+			ctx.print("\tint i;")
+			ctx.printf("\tfor (i = 0; i < %v; i++) {\n", opts.Procs)
+			ctx.print("\t\tif (fork() == 0) {\n")
 			if opts.HandleSegv {
-				fmt.Fprintf(w, "\t\t\tinstall_segv_handler();\n")
+				ctx.printf("\t\t\tinstall_segv_handler();\n")
 			}
 			if opts.UseTmpDir {
-				fmt.Fprintf(w, "\t\t\tuse_temporary_dir();\n")
+				ctx.printf("\t\t\tuse_temporary_dir();\n")
 			}
 			if opts.Sandbox != "" {
-				fmt.Fprintf(w, "\t\t\tint pid = do_sandbox_%v(i, %v);\n", opts.Sandbox, opts.EnableTun)
-				fmt.Fprint(w, "\t\t\tint status = 0;\n")
-				fmt.Fprint(w, "\t\t\twhile (waitpid(pid, &status, __WALL) != pid) {}\n")
+				ctx.printf("\t\t\tint pid = do_sandbox_%v(i, %v);\n", opts.Sandbox, opts.EnableTun)
+				ctx.print("\t\t\tint status = 0;\n")
+				ctx.print("\t\t\twhile (waitpid(pid, &status, __WALL) != pid) {}\n")
 			} else {
 				if opts.EnableTun {
-					fmt.Fprintf(w, "\t\t\tsetup_tun(i, %v);\n", opts.EnableTun)
+					ctx.printf("\t\t\tsetup_tun(i, %v);\n", opts.EnableTun)
 				}
-				fmt.Fprint(w, "\t\t\tloop();\n")
+				ctx.print("\t\t\tloop();\n")
 			}
-			fmt.Fprint(w, "\t\t\treturn 0;\n")
-			fmt.Fprint(w, "\t\t}\n")
-			fmt.Fprint(w, "\t}\n")
-			fmt.Fprint(w, "\tsleep(1000000);\n")
-			fmt.Fprint(w, "\treturn 0;\n}\n")
+			ctx.print("\t\t\treturn 0;\n")
+			ctx.print("\t\t}\n")
+			ctx.print("\t}\n")
+			ctx.print("\tsleep(1000000);\n")
+			ctx.print("\treturn 0;\n}\n")
 		}
 	}
 
 	// Remove NONFAILING and debug calls.
-	out0 := w.String()
+	out0 := ctx.w.String()
 	if !opts.HandleSegv {
 		re := regexp.MustCompile(`\t*NONFAILING\((.*)\);\n`)
 		out0 = re.ReplaceAllString(out0, "$1;\n")
@@ -211,64 +204,102 @@ func Write(p *prog.Prog, opts Options) ([]byte, error) {
 	return out1, nil
 }
 
-func generateTestFunc(w io.Writer, opts Options, calls []string, name string) {
+type context struct {
+	p         *prog.Prog
+	opts      Options
+	target    *prog.Target
+	sysTarget *targets.Target
+	w         *bytes.Buffer
+	calls     map[string]uint64 // CallName -> NR
+}
+
+func (ctx *context) print(str string) {
+	ctx.w.WriteString(str)
+}
+
+func (ctx *context) printf(str string, args ...interface{}) {
+	ctx.print(fmt.Sprintf(str, args...))
+}
+
+func (ctx *context) generateTestFunc(calls []string, name string) {
+	opts := ctx.opts
 	if !opts.Threaded && !opts.Collide {
-		fmt.Fprintf(w, "void %v()\n{\n", name)
+		ctx.printf("void %v()\n{\n", name)
 		if opts.Debug {
 			// Use debug to avoid: error: ‘debug’ defined but not used.
-			fmt.Fprintf(w, "\tdebug(\"%v\\n\");\n", name)
+			ctx.printf("\tdebug(\"%v\\n\");\n", name)
 		}
 		if opts.Repro {
-			fmt.Fprintf(w, "\tsyscall(SYS_write, 1, \"executing program\\n\", strlen(\"executing program\\n\"));\n")
+			ctx.printf("\tsyscall(SYS_write, 1, \"executing program\\n\", strlen(\"executing program\\n\"));\n")
 		}
-		fmt.Fprintf(w, "\tmemset(r, -1, sizeof(r));\n")
+		ctx.printf("\tmemset(r, -1, sizeof(r));\n")
 		for _, c := range calls {
-			fmt.Fprintf(w, "%s", c)
+			ctx.printf("%s", c)
 		}
-		fmt.Fprintf(w, "}\n\n")
+		ctx.printf("}\n\n")
 	} else {
-		fmt.Fprintf(w, "void *thr(void *arg)\n{\n")
-		fmt.Fprintf(w, "\tswitch ((long)arg) {\n")
+		ctx.printf("void *thr(void *arg)\n{\n")
+		ctx.printf("\tswitch ((long)arg) {\n")
 		for i, c := range calls {
-			fmt.Fprintf(w, "\tcase %v:\n", i)
-			fmt.Fprintf(w, "%s", strings.Replace(c, "\t", "\t\t", -1))
-			fmt.Fprintf(w, "\t\tbreak;\n")
+			ctx.printf("\tcase %v:\n", i)
+			ctx.printf("%s", strings.Replace(c, "\t", "\t\t", -1))
+			ctx.printf("\t\tbreak;\n")
 		}
-		fmt.Fprintf(w, "\t}\n")
-		fmt.Fprintf(w, "\treturn 0;\n}\n\n")
+		ctx.printf("\t}\n")
+		ctx.printf("\treturn 0;\n}\n\n")
 
-		fmt.Fprintf(w, "void %v()\n{\n", name)
-		fmt.Fprintf(w, "\tlong i;\n")
-		fmt.Fprintf(w, "\tpthread_t th[%v];\n", 2*len(calls))
-		fmt.Fprintf(w, "\n")
+		ctx.printf("void %v()\n{\n", name)
+		ctx.printf("\tlong i;\n")
+		ctx.printf("\tpthread_t th[%v];\n", 2*len(calls))
+		ctx.printf("\n")
 		if opts.Debug {
 			// Use debug to avoid: error: ‘debug’ defined but not used.
-			fmt.Fprintf(w, "\tdebug(\"%v\\n\");\n", name)
+			ctx.printf("\tdebug(\"%v\\n\");\n", name)
 		}
 		if opts.Repro {
-			fmt.Fprintf(w, "\tsyscall(SYS_write, 1, \"executing program\\n\", strlen(\"executing program\\n\"));\n")
+			ctx.printf("\tsyscall(SYS_write, 1, \"executing program\\n\", strlen(\"executing program\\n\"));\n")
 		}
-		fmt.Fprintf(w, "\tmemset(r, -1, sizeof(r));\n")
+		ctx.printf("\tmemset(r, -1, sizeof(r));\n")
 		if opts.Collide {
-			fmt.Fprintf(w, "\tsrand(getpid());\n")
+			ctx.printf("\tsrand(getpid());\n")
 		}
-		fmt.Fprintf(w, "\tfor (i = 0; i < %v; i++) {\n", len(calls))
-		fmt.Fprintf(w, "\t\tpthread_create(&th[i], 0, thr, (void*)i);\n")
-		fmt.Fprintf(w, "\t\tusleep(rand()%%10000);\n")
-		fmt.Fprintf(w, "\t}\n")
+		ctx.printf("\tfor (i = 0; i < %v; i++) {\n", len(calls))
+		ctx.printf("\t\tpthread_create(&th[i], 0, thr, (void*)i);\n")
+		ctx.printf("\t\tusleep(rand()%%10000);\n")
+		ctx.printf("\t}\n")
 		if opts.Collide {
-			fmt.Fprintf(w, "\tfor (i = 0; i < %v; i++) {\n", len(calls))
-			fmt.Fprintf(w, "\t\tpthread_create(&th[%v+i], 0, thr, (void*)i);\n", len(calls))
-			fmt.Fprintf(w, "\t\tif (rand()%%2)\n")
-			fmt.Fprintf(w, "\t\t\tusleep(rand()%%10000);\n")
-			fmt.Fprintf(w, "\t}\n")
+			ctx.printf("\tfor (i = 0; i < %v; i++) {\n", len(calls))
+			ctx.printf("\t\tpthread_create(&th[%v+i], 0, thr, (void*)i);\n", len(calls))
+			ctx.printf("\t\tif (rand()%%2)\n")
+			ctx.printf("\t\t\tusleep(rand()%%10000);\n")
+			ctx.printf("\t}\n")
+		}
+		ctx.printf("\tusleep(rand()%%100000);\n")
+		ctx.printf("}\n\n")
+	}
+}
+
+func (ctx *context) generateSyscallDefines() {
+	prefix := ctx.sysTarget.SyscallPrefix
+	for name, nr := range ctx.calls {
+		if strings.HasPrefix(name, "syz_") || !ctx.sysTarget.NeedSyscallDefine(nr) {
+			continue
 		}
-		fmt.Fprintf(w, "\tusleep(rand()%%100000);\n")
-		fmt.Fprintf(w, "}\n\n")
+		ctx.printf("#ifndef %v%v\n", prefix, name)
+		ctx.printf("#define %v%v %v\n", prefix, name, nr)
+		ctx.printf("#endif\n")
+	}
+	if ctx.target.OS == "linux" && ctx.target.PtrSize == 4 {
+		// This is a dirty hack.
+		// On 32-bit linux mmap translated to old_mmap syscall which has a different signature.
+		// mmap2 has the right signature. executor translates mmap to mmap2, do the same here.
+		ctx.printf("#undef __NR_mmap\n")
+		ctx.printf("#define __NR_mmap __NR_mmap2\n")
 	}
+	ctx.printf("\n")
 }
 
-func generateCalls(target *prog.Target, exec []byte, opts Options) ([]string, int) {
+func (ctx *context) generateCalls(exec []byte) ([]string, int) {
 	read := func() uint64 {
 		if len(exec) < 8 {
 			panic("exec program overflow")
@@ -372,23 +403,25 @@ loop:
 		default:
 			// Normal syscall.
 			newCall()
-			if opts.Fault && opts.FaultCall == len(calls) {
+			if ctx.opts.Fault && ctx.opts.FaultCall == len(calls) {
 				fmt.Fprintf(w, "\twrite_file(\"/sys/kernel/debug/failslab/ignore-gfp-wait\", \"N\");\n")
 				fmt.Fprintf(w, "\twrite_file(\"/sys/kernel/debug/fail_futex/ignore-private\", \"N\");\n")
-				fmt.Fprintf(w, "\tinject_fault(%v);\n", opts.FaultNth)
+				fmt.Fprintf(w, "\tinject_fault(%v);\n", ctx.opts.FaultNth)
 			}
-			meta := target.Syscalls[instr]
+			meta := ctx.target.Syscalls[instr]
 			emitCall := true
 			if meta.CallName == "syz_test" {
 				emitCall = false
 			}
-			if !opts.EnableTun && (meta.CallName == "syz_emit_ethernet" || meta.CallName == "syz_extract_tcp_res") {
+			if !ctx.opts.EnableTun && (meta.CallName == "syz_emit_ethernet" ||
+				meta.CallName == "syz_extract_tcp_res") {
 				emitCall = false
 			}
 			native := !strings.HasPrefix(meta.CallName, "syz_")
 			if emitCall {
 				if native {
-					fmt.Fprintf(w, "\tr[%v] = syscall(__NR_%v", n, meta.CallName)
+					fmt.Fprintf(w, "\tr[%v] = syscall(%v%v",
+						n, ctx.sysTarget.SyscallPrefix, meta.CallName)
 				} else {
 					fmt.Fprintf(w, "\tr[%v] = %v(", n, meta.CallName)
 				}
@@ -430,14 +463,15 @@ loop:
 	return calls, n
 }
 
-func preprocessCommonHeader(target *prog.Target, opts Options, handled map[string]uint64, useBitmasks, useChecksums bool) (string, error) {
+func (ctx *context) preprocessCommonHeader(commonHeader string) (string, error) {
 	var defines []string
-	if useBitmasks {
+	if prog.RequiresBitmasks(ctx.p) {
 		defines = append(defines, "SYZ_USE_BITMASKS")
 	}
-	if useChecksums {
+	if prog.RequiresChecksums(ctx.p) {
 		defines = append(defines, "SYZ_USE_CHECKSUMS")
 	}
+	opts := ctx.opts
 	switch opts.Sandbox {
 	case "":
 		// No sandbox, do nothing.
@@ -477,12 +511,10 @@ func preprocessCommonHeader(target *prog.Target, opts Options, handled map[strin
 	if opts.Debug {
 		defines = append(defines, "SYZ_DEBUG")
 	}
-	for name, _ := range handled {
+	for name, _ := range ctx.calls {
 		defines = append(defines, "__NR_"+name)
 	}
-
-	sysTarget := targets.List[target.OS][target.Arch]
-	defines = append(defines, sysTarget.CArch...)
+	defines = append(defines, ctx.sysTarget.CArch...)
 
 	cmd := exec.Command("cpp", "-nostdinc", "-undef", "-fdirectives-only", "-dDI", "-E", "-P", "-")
 	for _, def := range defines {