## heap-buffer-overflow, one_one_mapping, progs/dump_entry.c:1373, ncurses 6.1
POC: https://github.com/zjuchenyuan/fuzzpoc/raw/master/infotocap_poc1
```
# ./infotocap -o /dev/null infotocap_poc1
==34599==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x61c00000ff4e at pc 0x000000440933 bp 0x7ffffffeb1f0 sp 0x7ffffffeb1e0
READ of size 1 at 0x61c00000ff4e thread T0
#0 0x440932 in one_one_mapping ../progs/dump_entry.c:1373
#1 0x440932 in purged_acs ../progs/dump_entry.c:1399
#2 0x440932 in dump_entry ../progs/dump_entry.c:1561
#3 0x405006 in main ../progs/tic.c:1035
#4 0x7ffff6ac082f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2082f)
#5 0x408b98 in _start (/d/p/cveasan/infotocap+0x408b98)
0x61c00000ff4e is located 0 bytes to the right of 1742-byte region [0x61c00000f880,0x61c00000ff4e)
allocated by thread T0 here:
#0 0x7ffff6f02602 in malloc (/usr/lib/x86_64-linux-gnu/libasan.so.2+0x98602)
#1 0x4f492c in _nc_wrap_entry ../ncurses/./tinfo/alloc_entry.c:177
#2 0x62100001a4ff (<unknown module>)
SUMMARY: AddressSanitizer: heap-buffer-overflow ../progs/dump_entry.c:1373 one_one_mapping
Shadow bytes around the buggy address:
0x0c387fff9f90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c387fff9fa0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c387fff9fb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c387fff9fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c387fff9fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x0c387fff9fe0: 00 00 00 00 00 00 00 00 00[06]fa fa fa fa fa fa
0x0c387fff9ff0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0c387fffa000: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0c387fffa010: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0c387fffa020: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0c387fffa030: 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
Heap right redzone: fb
Freed heap region: fd
Stack left redzone: f1
Stack mid redzone: f2
Stack right redzone: f3
Stack partial redzone: f4
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
==34599==ABORTING
```
corresponding source code:
```
1366 static bool
1367 one_one_mapping(const char *mapping)
1368 {
1369 bool result = TRUE;
1370
1371 if (VALID_STRING(mapping)) {
1372 int n = 0;
1373 while (mapping[n] != '\0') {
1374 if (isLine(mapping[n]) &&
1375 mapping[n] != mapping[n + 1]) {
1376 result = FALSE;
1377 break;
1378 }
1379 n += 2;
1380 }
1381 }
1382 return result;
1383 }
```
Reproducible Docker image has been pushed to `zjuchenyuan/dockerized_poc:ncurses`, Dockerfile:
```
FROM zjuchenyuan/afl
ENV AFL_USE_ASAN=1 ASAN_OPTIONS="detect_leaks=0"
RUN git clone https://github.com/ThomasDickey/ncurses-snapshots &&\
cd ncurses-snapshots &&\
git checkout 8805e9e &&\
./configure --disable-shared &&\
make -j &&\
cp ./progs/tic /tmp/infotocap
RUN git clone https://github.com/zjuchenyuan/fuzzpoc
RUN /tmp/infotocap fuzzpoc/infotocap_poc1 || exit 0
```