C/C++ 动态检测内存错误利器 - ASan

[root@yglocal ~]# lsb_release -aLSB Version:    :core-4.1-amd64:core-4.1-noarchDistributor ID: CentOSDescription:    CentOS Linux release 8.1.1911 (Core) Release:        8.1.1911Codename:       Core[root@yglocal ~]# uname -r4.18.0-147.el8.x86_64[root@yglocal ~]# gcc --versiongcc (GCC) 8.3.1 20190507 (Red Hat 8.3.1-4)Copyright (C) 2018 Free Software Foundation, Inc.This is free software; see the source for copying conditions.  There is NOwarranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE

[root@localhost test]# gcc -g -O2 -fsanitize=address -fno-omit-frame-pointer hello.c /usr/bin/ld: cannot find /usr/lib64/libasan.so.0.0.0collect2: error: ld returned 1 exit status

[root@localhost test]# yum install libasan

[root@yglocal asan_test]# vi heap_ovf_test.c 
#include <stdio.h>#include <stdlib.h>#include <string.h>

int main(){        char *heap_buf = (char*)malloc(32*sizeof(char));        memcpy(heap_buf+30, "overflow", 8);    //在heap_buf的第30个字节开始，拷贝8个字符
        free(heap_buf);
        return 0;}

[root@yglocal asan_test]# gcc -fsanitize=address -fno-omit-frame-pointer -o heap_ovf_test heap_ovf_test.c [root@yglocal asan_test]# ./heap_ovf_test ===================================================================40602==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x603000000030 at pc 0x7f3de8f91a1d bp 0x7ffd4b4ebb60 sp 0x7ffd4b4eb308WRITE of size 8 at 0x603000000030 thread T0    #0 0x7f3de8f91a1c  (/lib64/libasan.so.5+0x40a1c)    #1 0x400845 in main (/root/asan_test/heap_ovf_test+0x400845)    #2 0x7f3de8bb1872 in __libc_start_main (/lib64/libc.so.6+0x23872)    #3 0x40075d in _start (/root/asan_test/heap_ovf_test+0x40075d)
0x603000000030 is located 0 bytes to the right of 32-byte region [0x603000000010,0x603000000030)allocated by thread T0 here:    #0 0x7f3de9040ba8 in __interceptor_malloc (/lib64/libasan.so.5+0xefba8)    #1 0x400827 in main (/root/asan_test/heap_ovf_test+0x400827)    #2 0x7f3de8bb1872 in __libc_start_main (/lib64/libc.so.6+0x23872)
SUMMARY: AddressSanitizer: heap-buffer-overflow (/lib64/libasan.so.5+0x40a1c) Shadow bytes around the buggy address:  0x0c067fff7fb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00=>0x0c067fff8000: fa fa 00 00 00 00[fa]fa fa fa fa fa fa fa fa fa  0x0c067fff8010: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8020: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8030: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8040: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8050: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa faShadow byte legend (one shadow byte represents 8 application bytes):  Addressable:           00  Partially addressable: 01 02 03 04 05 06 07   Heap left redzone:       fa  Freed heap region:       fd  Stack left redzone:      f1  Stack mid redzone:       f2  Stack right redzone:     f3  Stack after return:      f5  Stack use after scope:   f8  Global redzone:          f9  Global init order:       f6  Poisoned by user:        f7  Container overflow:      fc  Array cookie:            ac  Intra object redzone:    bb  ASan internal:           fe  Left alloca redzone:     ca  Right alloca redzone:    cb==40602==ABORTING[root@yglocal asan_test]#

[root@yglocal asan_test]# vi stack_ovf_test.c 
#include <stdio.h>#include <string.h>
int main(){        char stack_buf[4] = {0};        strcpy(stack_buf, "1234");
        return 0;}

[root@yglocal asan_test]# ./stack_ovf_test ===================================================================38634==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7ffcf3d8b8d4 at pc 0x7f8714bbaa1d bp 0x7ffcf3d8b8a0 sp 0x7ffcf3d8b048WRITE of size 5 at 0x7ffcf3d8b8d4 thread T0    #0 0x7f8714bbaa1c  (/lib64/libasan.so.5+0x40a1c)    #1 0x400949 in main (/root/asan_test/stack_ovf_test+0x400949)    #2 0x7f87147da872 in __libc_start_main (/lib64/libc.so.6+0x23872)    #3 0x4007cd in _start (/root/asan_test/stack_ovf_test+0x4007cd)
Address 0x7ffcf3d8b8d4 is located in stack of thread T0 at offset 36 in frame    #0 0x400895 in main (/root/asan_test/stack_ovf_test+0x400895)
  This frame has 1 object(s):    [32, 36) 'stack_buf' <== Memory access at offset 36 overflows this variableHINT: this may be a false positive if your program uses some custom stack unwind mechanism or swapcontext      (longjmp and C++ exceptions *are* supported)SUMMARY: AddressSanitizer: stack-buffer-overflow (/lib64/libasan.so.5+0x40a1c) Shadow bytes around the buggy address:  0x10001e7a96c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10001e7a96d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10001e7a96e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10001e7a96f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10001e7a9700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00=>0x10001e7a9710: 00 00 00 00 00 00 f1 f1 f1 f1[04]f2 f2 f2 f3 f3  0x10001e7a9720: f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10001e7a9730: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10001e7a9740: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10001e7a9750: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10001e7a9760: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00......

[root@yglocal asan_test]# vi dangling_pointer_test.c 
#include <stdio.h>#include <stdlib.h>#include <string.h>
int main(){        char *p = (char*)malloc(32*sizeof(char));        free(p);
        int a = p[1];
        return 0;}

[root@yglocal asan_test]# gcc -fsanitize=address -fno-omit-frame-pointer -o dangling_pointer_test dangling_pointer_test.c [root@yglocal asan_test]# ./dangling_pointer_test ===================================================================83532==ERROR: AddressSanitizer: heap-use-after-free on address 0x603000000011 at pc 0x0000004007c4 bp 0x7ffd7f562760 sp 0x7ffd7f562750READ of size 1 at 0x603000000011 thread T0    #0 0x4007c3 in main (/root/asan_test/dangling_pointer_test+0x4007c3)    #1 0x7f56196cd872 in __libc_start_main (/lib64/libc.so.6+0x23872)    #2 0x4006ad in _start (/root/asan_test/dangling_pointer_test+0x4006ad)
0x603000000011 is located 1 bytes inside of 32-byte region [0x603000000010,0x603000000030)freed by thread T0 here:    #0 0x7f5619b5c7e0 in __interceptor_free (/lib64/libasan.so.5+0xef7e0)    #1 0x400787 in main (/root/asan_test/dangling_pointer_test+0x400787)    #2 0x7f56196cd872 in __libc_start_main (/lib64/libc.so.6+0x23872)
previously allocated by thread T0 here:    #0 0x7f5619b5cba8 in __interceptor_malloc (/lib64/libasan.so.5+0xefba8)    #1 0x400777 in main (/root/asan_test/dangling_pointer_test+0x400777)    #2 0x7f56196cd872 in __libc_start_main (/lib64/libc.so.6+0x23872)
SUMMARY: AddressSanitizer: heap-use-after-free (/root/asan_test/dangling_pointer_test+0x4007c3) in mainShadow bytes around the buggy address:  0x0c067fff7fb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00=>0x0c067fff8000: fa fa[fd]fd fd fd fa fa fa fa fa fa fa fa fa fa  0x0c067fff8010: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8020: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8030: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8040: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8050: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa faShadow byte legend (one shadow byte represents 8 application bytes):......

[root@yglocal asan_test]# vi use-after-return.c 
#include <stdio.h>#include <stdlib.h>#include <string.h>int *ptr;void get_pointer(){        int local[10];        ptr = &local[0];        return;}

int main(){        get_pointer();
        printf("%d\n", *ptr);
        return 0;}

[root@yglocal asan_test]# gcc -fsanitize=address -fno-omit-frame-pointer -o use_after_return use-after-return.c[root@yglocal asan_test]# ASAN_OPTIONS=detect_stack_use_after_return=1 ./use_after_return ===================================================================108419==ERROR: AddressSanitizer: stack-use-after-return on address 0x7fa2de200020 at pc 0x0000004009a2 bp 0x7ffccaef23c0 sp 0x7ffccaef23b0READ of size 4 at 0x7fa2de200020 thread T0    #0 0x4009a1 in main (/root/asan_test/use_after_return+0x4009a1)    #1 0x7fa2e264d872 in __libc_start_main (/lib64/libc.so.6+0x23872)    #2 0x4007cd in _start (/root/asan_test/use_after_return+0x4007cd)
Address 0x7fa2de200020 is located in stack of thread T0 at offset 32 in frame    #0 0x400895 in get_pointer (/root/asan_test/use_after_return+0x400895)
  This frame has 1 object(s):    [32, 72) 'local' <== Memory access at offset 32 is inside this variableHINT: this may be a false positive if your program uses some custom stack unwind mechanism or swapcontext      (longjmp and C++ exceptions *are* supported)SUMMARY: AddressSanitizer: stack-use-after-return (/root/asan_test/use_after_return+0x4009a1) in mainShadow bytes around the buggy address:  0x0ff4dbc37fb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0ff4dbc37fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0ff4dbc37fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0ff4dbc37fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0ff4dbc37ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00=>0x0ff4dbc38000: f5 f5 f5 f5[f5]f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5  0x0ff4dbc38010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0ff4dbc38020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0ff4dbc38030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0ff4dbc38040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0ff4dbc38050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00......

[root@yglocal asan_test]# vi use-after-scope.c  #include <stdio.h>#include <stdlib.h>#include <string.h> int main(){        int *p;        {                int num = 10;                p = &num;        }        printf("%d/n", *p);         return 0;}

[root@yglocal asan_test]# ./use-after-scope ===================================================================45490==ERROR: AddressSanitizer: stack-use-after-scope on address 0x7fffda668b50 at pc 0x0000004009ea bp 0x7fffda668b10 sp 0x7fffda668b00READ of size 4 at 0x7fffda668b50 thread T0    #0 0x4009e9 in main (/root/asan_test/use-after-scope+0x4009e9)    #1 0x7fc2194ca872 in __libc_start_main (/lib64/libc.so.6+0x23872)    #2 0x40082d in _start (/root/asan_test/use-after-scope+0x40082d) Address 0x7fffda668b50 is located in stack of thread T0 at offset 32 in frame    #0 0x4008f5 in main (/root/asan_test/use-after-scope+0x4008f5)   This frame has 1 object(s):    [32, 36) 'num' <== Memory access at offset 32 is inside this variableHINT: this may be a false positive if your program uses some custom stack unwind mechanism or swapcontext      (longjmp and C++ exceptions *are* supported)SUMMARY: AddressSanitizer: stack-use-after-scope (/root/asan_test/use-after-scope+0x4009e9) in mainShadow bytes around the buggy address:  0x10007b4c5110: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10007b4c5120: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10007b4c5130: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10007b4c5140: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10007b4c5150: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00=>0x10007b4c5160: 00 00 00 00 00 00 f1 f1 f1 f1[f8]f2 f2 f2 f3 f3  0x10007b4c5170: f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10007b4c5180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10007b4c5190: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10007b4c51a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x10007b4c51b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00......[root@yglocal asan_test]#

[root@yglocal asan_test]# vi invalid_free_test.c  #include <stdio.h>#include <stdlib.h> int main(){        char *p = (char*)malloc(32*sizeof(char));        free(p);        free(p);         return 0;} 

[root@yglocal asan_test]# gcc -fsanitize=address -fno-omit-frame-pointer -o invalid_free_test invalid_free_test.c [root@yglocal asan_test]# ./invalid_free_test ===================================================================116778==ERROR: AddressSanitizer: attempting double-free on 0x603000000010 in thread T0:    #0 0x7fab036ca7e0 in __interceptor_free (/lib64/libasan.so.5+0xef7e0)    #1 0x400743 in main (/root/asan_test/invalid_free_test+0x400743)    #2 0x7fab0323b872 in __libc_start_main (/lib64/libc.so.6+0x23872)    #3 0x40065d in _start (/root/asan_test/invalid_free_test+0x40065d) 0x603000000010 is located 0 bytes inside of 32-byte region [0x603000000010,0x603000000030)freed by thread T0 here:    #0 0x7fab036ca7e0 in __interceptor_free (/lib64/libasan.so.5+0xef7e0)    #1 0x400737 in main (/root/asan_test/invalid_free_test+0x400737)    #2 0x7fab0323b872 in __libc_start_main (/lib64/libc.so.6+0x23872) previously allocated by thread T0 here:    #0 0x7fab036caba8 in __interceptor_malloc (/lib64/libasan.so.5+0xefba8)    #1 0x400727 in main (/root/asan_test/invalid_free_test+0x400727)    #2 0x7fab0323b872 in __libc_start_main (/lib64/libc.so.6+0x23872) SUMMARY: AddressSanitizer: double-free (/lib64/libasan.so.5+0xef7e0) in __interceptor_free==116778==ABORTING

[root@yglocal asan_test]# vi use-after-scope.c #include <stdio.h>#include <stdlib.h> int main(){        int *p;        {                int num = 10;                p = &num;        }        printf("%d/n", *p);         return 0;}

[root@yglocal asan_test]# gcc -fsanitize=address -fno-omit-frame-pointer -o use-after-scope use-after-scope.c [root@yglocal asan_test]# ./use-after-scope ===================================================================118523==ERROR: AddressSanitizer: stack-use-after-scope on address 0x7ffd35fafc60 at pc 0x0000004009ea bp 0x7ffd35fafc20 sp 0x7ffd35fafc10READ of size 4 at 0x7ffd35fafc60 thread T0    #0 0x4009e9 in main (/root/asan_test/use-after-scope+0x4009e9)    #1 0x7f6d2c4ce872 in __libc_start_main (/lib64/libc.so.6+0x23872)    #2 0x40082d in _start (/root/asan_test/use-after-scope+0x40082d) Address 0x7ffd35fafc60 is located in stack of thread T0 at offset 32 in frame    #0 0x4008f5 in main (/root/asan_test/use-after-scope+0x4008f5)   This frame has 1 object(s):    [32, 36) 'num' <== Memory access at offset 32 is inside this variableHINT: this may be a false positive if your program uses some custom stack unwind mechanism or swapcontext      (longjmp and C++ exceptions *are* supported)SUMMARY: AddressSanitizer: stack-use-after-scope (/root/asan_test/use-after-scope+0x4009e9) in mainShadow bytes around the buggy address:  0x100026bedf30: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x100026bedf40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x100026bedf50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x100026bedf60: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x100026bedf70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00=>0x100026bedf80: 00 00 00 00 00 00 00 00 f1 f1 f1 f1[f8]f2 f2 f2  0x100026bedf90: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00  0x100026bedfa0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x100026bedfb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x100026bedfc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x100026bedfd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00......

[root@yglocal asan_test]# vi memory_leak_test.c   #include <stdio.h>#include <stdlib.h>#include <string.h> char* get_systeminfo(){        char *p_system = (char*)malloc(38*sizeof(char));        strcpy(p_system, "Linux version 4.18.0-147.el8.x86_64");        return p_system;} int main(){        printf("system info:%s", get_systeminfo());        return 0;}

[root@yglocal asan_test]# gcc -fsanitize=address -fno-omit-frame-pointer -o memory_leak_test memory_leak_test.c[root@yglocal asan_test]# ASAN_OPTIONS=detect_leaks=1  ./memory_leak_test  ===================================================================122316==ERROR: LeakSanitizer: detected memory leaks Direct leak of 38 byte(s) in 1 object(s) allocated from:    #0 0x7fde593f3ba8 in __interceptor_malloc (/lib64/libasan.so.5+0xefba8)    #1 0x400827 in get_systeminfo (/root/asan_test/memory_leak_test+0x400827)    #2 0x400855 in main (/root/asan_test/memory_leak_test+0x400855)    #3 0x7fde58f64872 in __libc_start_main (/lib64/libc.so.6+0x23872) SUMMARY: AddressSanitizer: 38 byte(s) leaked in 1 allocation(s).

[root@yglocal asan_test]# ASAN_OPTIONS='stack_trace_format="[frame=%n, function=%f, location=%S]"' ./heap_ovf_test ===================================================================31061==ERROR: AddressSanitizer: heap-use-after-free on address 0x603000000010 at pc 0x7f181e836796 bp 0x7ffd87d62c30 sp 0x7ffd87d623a8READ of size 2 at 0x603000000010 thread T0[frame=0, function=<null>, location=<null>][frame=1, function=__interceptor_vprintf, location=<null>][frame=2, function=__interceptor_printf, location=<null>][frame=3, function=main, location=<null>][frame=4, function=__libc_start_main, location=<null>][frame=5, function=_start, location=<null>] 0x603000000010 is located 0 bytes inside of 32-byte region [0x603000000010,0x603000000030)freed by thread T0 here:[frame=0, function=__interceptor_free, location=<null>][frame=1, function=main, location=<null>][frame=2, function=__libc_start_main, location=<null>] previously allocated by thread T0 here:[frame=0, function=__interceptor_malloc, location=<null>][frame=1, function=main, location=<null>][frame=2, function=__libc_start_main, location=<null>] SUMMARY: AddressSanitizer: heap-use-after-free (/lib64/libasan.so.5+0x55795) Shadow bytes around the buggy address:  0x0c067fff7fb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00=>0x0c067fff8000: fa fa[fd]fd fd fd fa fa fa fa fa fa fa fa fa fa  0x0c067fff8010: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8020: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8030: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8040: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8050: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa faShadow byte legend (one shadow byte represents 8 application bytes):  Addressable:           00  Partially addressable: 01 02 03 04 05 06 07   Heap left redzone:       fa  Freed heap region:       fd  Stack left redzone:      f1  Stack mid redzone:       f2  Stack right redzone:     f3  Stack after return:      f5  Stack use after scope:   f8  Global redzone:          f9  Global init order:       f6  Poisoned by user:        f7  Container overflow:      fc  Array cookie:            ac  Intra object redzone:    bb  ASan internal:           fe  Left alloca redzone:     ca  Right alloca redzone:    cb==31061==ABORTING

[root@yglocal asan_test]# gcc -fsanitize=address -fno-omit-frame-pointer -g -o heap_ovf_test heap_ovf_test.c [root@yglocal asan_test]# ./heap_ovf_test 2>&1 | ./asan_symbolize.py ===================================================================66336==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x603000000030 at pc 0x7f0e8b19ea1d bp 0x7ffc0764d8a0 sp 0x7ffc0764d048WRITE of size 8 at 0x603000000030 thread T0    #0 0x7f0e8b19ea1c in __interceptor_strpbrk ??:?    #1 0x400845 in main /root/asan_test/heap_ovf_test.c:9    #1 0x7f0e8adbe872 in __libc_start_main ??:?    #2 0x40075d in _start ??:? 0x603000000030 is located 0 bytes to the right of 32-byte region [0x603000000010,0x603000000030)allocated by thread T0 here:    #0 0x7f0e8b24dba8 in malloc ??:?    #1 0x400827 in main /root/asan_test/heap_ovf_test.c:8    #1 0x7f0e8adbe872 in __libc_start_main ??:? SUMMARY: AddressSanitizer: heap-buffer-overflow (/lib64/libasan.so.5+0x40a1c)Shadow bytes around the buggy address:  0x0c067fff7fb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  0x0c067fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00=>0x0c067fff8000: fa fa 00 00 00 00[fa]fa fa fa fa fa fa fa fa fa  0x0c067fff8010: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8020: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8030: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8040: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa  0x0c067fff8050: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa faShadow byte legend (one shadow byte represents 8 application bytes):  Addressable:           00  Partially addressable: 01 02 03 04 05 06 07  Heap left redzone:       fa  Freed heap region:       fd  Stack left redzone:      f1  Stack mid redzone:       f2  Stack right redzone:     f3  Stack after return:      f5  Stack use after scope:   f8  Global redzone:          f9  Global init order:       f6  Poisoned by user:        f7  Container overflow:      fc  Array cookie:            ac  Intra object redzone:    bb  ASan internal:           fe  Left alloca redzone:     ca  Right alloca redzone:    cb==66336==ABORTING

[root@yglocal asan_test]# ASAN_OPTIONS=help=1 ./use-after-scope Available flags for AddressSanitizer:        ......        debug                - If set, prints some debugging information and does additional checks.        check_initialization_order               - If set, attempts to catch initialization order issues.        replace_str                - If set, uses custom wrappers and replacements for libc string functions to find more errors.        replace_intrin                - If set, uses custom wrappers for memset/memcpy/memmove intrinsics.        detect_stack_use_after_return                - Enables stack-use-after-return checking at run-time.        ......                - Number of seconds to sleep after AddressSanitizer is initialized. Useful for debugging purposes (e.g. when one needs to attach gdb).        check_malloc_usable_size                - Allows the users to work around the bug in Nvidia drivers prior to 295.*.        unmap_shadow_on_exit                - If set, explicitly unmaps the (huge) shadow at exit.        protect_shadow_gap                - If set, mprotect the shadow gap        print_stats                - Print various statistics after printing an error message or if atexit=1.        print_legend                - Print the legend for the shadow bytes.        print_scariness                - Print the scariness score. Experimental.        ......                - If true, ASan tweaks a bunch of other flags (quarantine, redzone, heap poisoning) to reduce memory consumption as much as possible, and restores them to original values when the first instrumented module is loaded into the process. This is mainly intended to be used on Android.         detect_invalid_pointer_pairs                - If >= 2, detect operations like <, <=, >, >= and - on invalid pointer pairs (e.g. when pointers belong to different objects); If == 1, detect invalid operations only when both pointers are non-null.        detect_container_overflow                - If true, honor the container overflow annotations. See https://github.com/google/sanitizers/wiki/AddressSanitizerContainerOverflow        detect_odr_violation                - If >=2, detect violation of One-Definition-Rule (ODR); If ==1, detect ODR-violation only if the two variables have different sizes        suppressions                - Suppressions file name.        halt_on_error                - Crash the program after printing the first error report (WARNING: USE AT YOUR OWN RISK!)        use_odr_indicator                - Use special ODR indicator symbol for ODR violation detection        allocator_frees_and_returns_null_on_realloc_zero                - realloc(p, 0) is equivalent to free(p) by default (Same as the POSIX standard). If set to false, realloc(p, 0) will return a pointer to an allocated space which can not be used.        verify_asan_link_order                - Check position of ASan runtime in library list (needs to be disabled when other library has to be preloaded system-wide)        symbolize                - If set, use the online symbolizer from common sanitizer runtime to turn virtual addresses to file/line locations.        external_symbolizer_path                - Path to external symbolizer. If empty, the tool will search $PATH for the symbolizer.        allow_addr2line                - If set, allows online symbolizer to run addr2line binary to symbolize stack traces (addr2line will only be used if llvm-symbolizer binary is unavailable.        strip_path_prefix                - Strips this prefix from file paths in error reports.        ......