1 //===- FuzzerUtilPosix.cpp - Misc utils for Posix. ------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 // Misc utils implementation using Posix API.
10 //===----------------------------------------------------------------------===//
11 #include "FuzzerDefs.h"
12 #if LIBFUZZER_POSIX
13 #include "FuzzerIO.h"
14 #include "FuzzerInternal.h"
15 #include <cassert>
16 #include <chrono>
17 #include <cstring>
18 #include <errno.h>
19 #include <iomanip>
20 #include <signal.h>
21 #include <stdio.h>
22 #include <sys/resource.h>
23 #include <sys/syscall.h>
24 #include <sys/time.h>
25 #include <sys/types.h>
26 #include <thread>
27 #include <unistd.h>
28
29 namespace fuzzer {
30
AlarmHandler(int,siginfo_t *,void *)31 static void AlarmHandler(int, siginfo_t *, void *) {
32 Fuzzer::StaticAlarmCallback();
33 }
34
CrashHandler(int,siginfo_t *,void *)35 static void CrashHandler(int, siginfo_t *, void *) {
36 Fuzzer::StaticCrashSignalCallback();
37 }
38
InterruptHandler(int,siginfo_t *,void *)39 static void InterruptHandler(int, siginfo_t *, void *) {
40 Fuzzer::StaticInterruptCallback();
41 }
42
GracefulExitHandler(int,siginfo_t *,void *)43 static void GracefulExitHandler(int, siginfo_t *, void *) {
44 Fuzzer::StaticGracefulExitCallback();
45 }
46
FileSizeExceedHandler(int,siginfo_t *,void *)47 static void FileSizeExceedHandler(int, siginfo_t *, void *) {
48 Fuzzer::StaticFileSizeExceedCallback();
49 }
50
SetSigaction(int signum,void (* callback)(int,siginfo_t *,void *))51 static void SetSigaction(int signum,
52 void (*callback)(int, siginfo_t *, void *)) {
53 struct sigaction sigact = {};
54 if (sigaction(signum, nullptr, &sigact)) {
55 Printf("libFuzzer: sigaction failed with %d\n", errno);
56 exit(1);
57 }
58 if (sigact.sa_flags & SA_SIGINFO) {
59 if (sigact.sa_sigaction)
60 return;
61 } else {
62 if (sigact.sa_handler != SIG_DFL && sigact.sa_handler != SIG_IGN &&
63 sigact.sa_handler != SIG_ERR)
64 return;
65 }
66
67 sigact = {};
68 sigact.sa_sigaction = callback;
69 if (sigaction(signum, &sigact, 0)) {
70 Printf("libFuzzer: sigaction failed with %d\n", errno);
71 exit(1);
72 }
73 }
74
SetTimer(int Seconds)75 void SetTimer(int Seconds) {
76 struct itimerval T {
77 {Seconds, 0}, { Seconds, 0 }
78 };
79 if (setitimer(ITIMER_REAL, &T, nullptr)) {
80 Printf("libFuzzer: setitimer failed with %d\n", errno);
81 exit(1);
82 }
83 SetSigaction(SIGALRM, AlarmHandler);
84 }
85
SetSignalHandler(const FuzzingOptions & Options)86 void SetSignalHandler(const FuzzingOptions& Options) {
87 if (Options.UnitTimeoutSec > 0)
88 SetTimer(Options.UnitTimeoutSec / 2 + 1);
89 if (Options.HandleInt)
90 SetSigaction(SIGINT, InterruptHandler);
91 if (Options.HandleTerm)
92 SetSigaction(SIGTERM, InterruptHandler);
93 if (Options.HandleSegv)
94 SetSigaction(SIGSEGV, CrashHandler);
95 if (Options.HandleBus)
96 SetSigaction(SIGBUS, CrashHandler);
97 if (Options.HandleAbrt)
98 SetSigaction(SIGABRT, CrashHandler);
99 if (Options.HandleIll)
100 SetSigaction(SIGILL, CrashHandler);
101 if (Options.HandleFpe)
102 SetSigaction(SIGFPE, CrashHandler);
103 if (Options.HandleXfsz)
104 SetSigaction(SIGXFSZ, FileSizeExceedHandler);
105 if (Options.HandleUsr1)
106 SetSigaction(SIGUSR1, GracefulExitHandler);
107 if (Options.HandleUsr2)
108 SetSigaction(SIGUSR2, GracefulExitHandler);
109 }
110
SleepSeconds(int Seconds)111 void SleepSeconds(int Seconds) {
112 sleep(Seconds); // Use C API to avoid coverage from instrumented libc++.
113 }
114
GetPid()115 unsigned long GetPid() { return (unsigned long)getpid(); }
116
GetPeakRSSMb()117 size_t GetPeakRSSMb() {
118 struct rusage usage;
119 if (getrusage(RUSAGE_SELF, &usage))
120 return 0;
121 if (LIBFUZZER_LINUX || LIBFUZZER_FREEBSD || LIBFUZZER_NETBSD ||
122 LIBFUZZER_OPENBSD) {
123 // ru_maxrss is in KiB
124 return usage.ru_maxrss >> 10;
125 } else if (LIBFUZZER_APPLE) {
126 // ru_maxrss is in bytes
127 return usage.ru_maxrss >> 20;
128 }
129 assert(0 && "GetPeakRSSMb() is not implemented for your platform");
130 return 0;
131 }
132
OpenProcessPipe(const char * Command,const char * Mode)133 FILE *OpenProcessPipe(const char *Command, const char *Mode) {
134 return popen(Command, Mode);
135 }
136
SearchMemory(const void * Data,size_t DataLen,const void * Patt,size_t PattLen)137 const void *SearchMemory(const void *Data, size_t DataLen, const void *Patt,
138 size_t PattLen) {
139 return memmem(Data, DataLen, Patt, PattLen);
140 }
141
DisassembleCmd(const std::string & FileName)142 std::string DisassembleCmd(const std::string &FileName) {
143 return "objdump -d " + FileName;
144 }
145
SearchRegexCmd(const std::string & Regex)146 std::string SearchRegexCmd(const std::string &Regex) {
147 return "grep '" + Regex + "'";
148 }
149
150 } // namespace fuzzer
151
152 #endif // LIBFUZZER_POSIX
153