| // Copyright 2017 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. |
| |
| package main |
| |
| import ( |
| "fmt" |
| "strings" |
| "time" |
| |
| "github.com/google/syzkaller/pkg/compiler" |
| "github.com/google/syzkaller/pkg/osutil" |
| ) |
| |
| type linux struct{} |
| |
| func (*linux) prepare(sourcedir string, build bool, arches []string) error { |
| if sourcedir == "" { |
| return fmt.Errorf("provide path to kernel checkout via -sourcedir flag (or make extract SOURCEDIR)") |
| } |
| if build { |
| // Otherwise out-of-tree build fails. |
| fmt.Printf("make mrproper\n") |
| out, err := osutil.RunCmd(time.Hour, sourcedir, "make", "mrproper") |
| if err != nil { |
| return fmt.Errorf("make mrproper failed: %v\n%s\n", err, out) |
| } |
| } else { |
| if len(arches) > 1 { |
| return fmt.Errorf("more than 1 arch is invalid without -build") |
| } |
| } |
| return nil |
| } |
| |
| func (*linux) prepareArch(arch *Arch) error { |
| if !arch.build { |
| return nil |
| } |
| target := arch.target |
| kernelDir := arch.sourceDir |
| buildDir := arch.buildDir |
| makeArgs := []string{ |
| "ARCH=" + target.KernelArch, |
| "CROSS_COMPILE=" + target.CCompilerPrefix, |
| "CFLAGS=" + strings.Join(target.CrossCFlags, " "), |
| "O=" + buildDir, |
| } |
| out, err := osutil.RunCmd(time.Hour, kernelDir, "make", append(makeArgs, "defconfig")...) |
| if err != nil { |
| return fmt.Errorf("make defconfig failed: %v\n%s\n", err, out) |
| } |
| // Without CONFIG_NETFILTER kernel does not build. |
| out, 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\n", err, out) |
| } |
| out, err = osutil.RunCmd(time.Hour, kernelDir, "make", append(makeArgs, "olddefconfig")...) |
| if err != nil { |
| return fmt.Errorf("make olddefconfig failed: %v\n%s\n", err, out) |
| } |
| out, err = osutil.RunCmd(time.Hour, kernelDir, "make", append(makeArgs, "init/main.o")...) |
| if err != nil { |
| return fmt.Errorf("make failed: %v\n%s\n", err, out) |
| } |
| return nil |
| } |
| |
| func (*linux) processFile(arch *Arch, info *compiler.ConstInfo) (map[string]uint64, map[string]bool, error) { |
| headerArch := arch.target.KernelHeaderArch |
| sourceDir := arch.sourceDir |
| buildDir := arch.buildDir |
| args := []string{ |
| // This would be useful to ensure that we don't include any host headers, |
| // but kernel includes at least <stdarg.h> |
| // "-nostdinc", |
| "-w", "-fmessage-length=0", |
| "-O3", // required to get expected values for some __builtin_constant_p |
| "-I.", |
| "-D__KERNEL__", |
| "-DKBUILD_MODNAME=\"-\"", |
| "-I" + sourceDir + "/arch/" + headerArch + "/include", |
| "-I" + buildDir + "/arch/" + headerArch + "/include/generated/uapi", |
| "-I" + buildDir + "/arch/" + headerArch + "/include/generated", |
| "-I" + buildDir + "/include", |
| "-I" + sourceDir + "/include", |
| "-I" + sourceDir + "/arch/" + headerArch + "/include/uapi", |
| "-I" + buildDir + "/arch/" + headerArch + "/include/generated/uapi", |
| "-I" + sourceDir + "/include/uapi", |
| "-I" + buildDir + "/include/generated/uapi", |
| "-I" + sourceDir, |
| "-include", sourceDir + "/include/linux/kconfig.h", |
| } |
| args = append(args, arch.target.CFlags...) |
| for _, incdir := range info.Incdirs { |
| args = append(args, "-I"+sourceDir+"/"+incdir) |
| } |
| const addSource = ` |
| #include <asm/unistd.h> |
| unsigned long phys_base; |
| #ifndef __phys_addr |
| unsigned long __phys_addr(unsigned long addr) { return 0; } |
| #endif |
| ` |
| res, undeclared, err := extract(info, "gcc", args, addSource, true) |
| if err != nil { |
| return nil, nil, err |
| } |
| if arch.target.PtrSize == 4 { |
| // mmap syscall on i386/arm is translated to old_mmap and has different signature. |
| // As a workaround fix it up to mmap2, which has signature that we expect. |
| // pkg/csource has the same hack. |
| const mmap = "__NR_mmap" |
| const mmap2 = "__NR_mmap2" |
| if res[mmap] != 0 || undeclared[mmap] { |
| if res[mmap2] == 0 { |
| return nil, nil, fmt.Errorf("%v is missing", mmap2) |
| } |
| res[mmap] = res[mmap2] |
| delete(undeclared, mmap) |
| } |
| } |
| return res, undeclared, nil |
| } |