RfbRegisterProtocolExtension () function will trigger the heap - use - after - free defects

[Dabiaoge6]

testcase:

EASYFUZZ(QeEmLbyx){

    rfbProtocolExtension * extension_sKWcnQYh = (rfbProtocolExtension *)calloc(1, sizeof(rfbProtocolExtension));
     extension_sKWcnQYh->pseudoEncodings = (int *) fuzzInt32(0);

    rfbRegisterProtocolExtension(extension_sKWcnQYh);

    free(extension_sKWcnQYh);

}

Crashlog:

==2856==ERROR: AddressSanitizer: heap-use-after-free on address 0x607000000140 at pc 0x7f73ecd57669 bp 0x7ffeae7787d0 sp 0x7ffeae7787c0 READ of size 8 at 0x607000000140 thread T0

0 0x7f73ecd57668 in rfbRegisterProtocolExtension /cloud_proj/pr1679995373267xbruewtfxojxvgnl/libvncserver/main.c:94

#1 0x55b77f53a6ca in easyloop /dockerin/test_file.c:40
#2 0x55b77f53a40b in main /opt1/software/betafuzz/srap/wrapentry.c:108
#3 0x7f73eca6fd8f  (/lib/x86_64-linux-gnu/libc.so.6+0x29d8f)
#4 0x7f73eca6fe3f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e3f)
#5 0x55b77f53a464 in _start (/dockerin/clouditera+0x1464)

0x607000000140 is located 64 bytes inside of 72-byte region [0x607000000100,0x607000000148) freed by thread T0 here:

0 0x7f73ecf41517 in __interceptor_free ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:127

#1 0x55b77f53a6d9 in easyloop /dockerin/test_file.c:44
#2 0x55b77f53a40b in main /opt1/software/betafuzz/srap/wrapentry.c:108

previously allocated by thread T0 here:

0 0x7f73ecf41a37 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154

#1 0x55b77f53a672 in easyloop /dockerin/test_file.c:18
#2 0x55b77f53a40b in main /opt1/software/betafuzz/srap/wrapentry.c:108

SUMMARY: AddressSanitizer: heap-use-after-free /cloud_proj/pr1679995373267xbruewtfxojxvgnl/libvncserver/main.c:94 in rfbRegisterProtocolExtension Shadow bytes around the buggy address: 0x0c0e7fff7fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0c0e7fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0c0e7fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0c0e7fff8000: fa fa fa fa fd fd fd fd fd fd fd fd fd fa fa fa 0x0c0e7fff8010: fa fa 00 00 00 00 00 00 00 00 05 fa fa fa fa fa =>0x0c0e7fff8020: fd fd fd fd fd fd fd fd[fd]fa fa fa fa fa 00 00 0x0c0e7fff8030: 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa fa 0x0c0e7fff8040: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c0e7fff8050: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c0e7fff8060: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c0e7fff8070: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa Shadow 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 Shadow gap: cc

[bk138]

@Dabiaoge6 how to reproduce this step by step? Please post the framework you were using and the complete source of wrapentry.c

[bk138]

Tentatively closing as there's no way to repo. Please post new info here once available.