Submit #554574: UnQLite mater Heap-based Buffer Overflow

Hi,

We found a heap buffer overflow using a new concolic execution tool. Please check the below and the attached file for reproduction.

```
$cd build/example
$./unqlitec input.sql
=================================================================
==19425==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x61b000001c5c at pc 0x555555796fad bp 0x7fffffffc3c0 sp 0x7fffffffc3b0
READ of size 4 at 0x61b000001c5c thread T0
#0 0x555555796fac in jx9MemObjStore /data/src/benchmarks/unqlite/unqlite.c:31737
#1 0x5555557d4504 in VmByteCodeExec /data/src/benchmarks/unqlite/unqlite.c:43880
#2 0x5555557e00d1 in jx9VmByteCodeExec /data/src/benchmarks/unqlite/unqlite.c:45623
#3 0x5555556f4d2e in unqlite_vm_exec /data/src/benchmarks/unqlite/unqlite.c:4572
#4 0x5555556f0821 in execute_sql_commands /data/src/benchmarks/unqlite/example/unqlite.c:72
#5 0x5555556f0ee0 in main /data/src/benchmarks/unqlite/example/unqlite.c:101
#6 0x7ffff6e22c86 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21c86)
#7 0x5555555f1a19 in _start (/data/src/benchmarks/unqlite/build-gcov/example/unqlitec+0x9da19)

0x61b000001c5c is located 36 bytes to the left of 1428-byte region [0x61b000001c80,0x61b000002214)
allocated by thread T0 here:
#0 0x5555556af7f0 in malloc (/data/src/benchmarks/unqlite/build-gcov/example/unqlitec+0x15b7f0)
#1 0x555555773d96 in SyOSHeapAlloc /data/src/benchmarks/unqlite/unqlite.c:26911
#2 0x555555777366 in MemOSAlloc /data/src/benchmarks/unqlite/unqlite.c:27100
#3 0x55555577763b in MemBackendAlloc /data/src/benchmarks/unqlite/unqlite.c:27154
#4 0x5555557779fd in SyMemBackendAlloc /data/src/benchmarks/unqlite/unqlite.c:27184
#5 0x5555557cb0c9 in VmNewOperandStack /data/src/benchmarks/unqlite/unqlite.c:42476
#6 0x5555557cb342 in jx9VmMakeReady /data/src/benchmarks/unqlite/unqlite.c:42516
#7 0x5555557016b2 in ProcessScript /data/src/benchmarks/unqlite/unqlite.c:7557
#8 0x555555701b66 in jx9_compile /data/src/benchmarks/unqlite/unqlite.c:7615
#9 0x5555556f454d in unqlite_compile /data/src/benchmarks/unqlite/unqlite.c:4466
#10 0x5555556f0471 in execute_sql_commands /data/src/benchmarks/unqlite/example/unqlite.c:51
#11 0x5555556f0ee0 in main /data/src/benchmarks/unqlite/example/unqlite.c:101
#12 0x7ffff6e22c86 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21c86)

SUMMARY: AddressSanitizer: heap-buffer-overflow /data/src/benchmarks/unqlite/unqlite.c:31737 in jx9MemObjStore
Shadow bytes around the buggy address:
0x0c367fff8330: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x0c367fff8340: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x0c367fff8350: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x0c367fff8360: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x0c367fff8370: fd fd fd fa fa fa fa fa fa fa fa fa fa fa fa fa
=>0x0c367fff8380: fa fa fa fa fa fa fa fa fa fa fa[fa]fa fa fa fa
0x0c367fff8390: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c367fff83a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c367fff83b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c367fff83c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c367fff83d0: 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
==19425==ABORTING

```

Building instruction `cmake -DCMAKE_C_COMPILER=gcc -DCMAKE_C_FLAGS="-g -fsanitize=address" ..`
GCC version `gcc-7.5.0`
OS: `x86_64 ubuntu 18.04`
Git version of unqlite `957c377cb691a4f617db9aba5cc46d90425071e2` (master)
Reproducible files [unqlite-reproduce-heap-overflow.zip](https://github.com/user-attachments/files/19652580/unqlite-reproduce-heap-overflow.zip)

Best regards,
Hx

• Quelle: ⚠️ https://github.com/symisc/unqlite/issues/173
• Benutzer: Haoxin Tu (UID 81718)
• Einreichung: 09.04.2025 03:53 (vor 1 Jahr)
• Moderieren: 18.04.2025 04:49 (9 days later)
• Status: Akzeptiert
• VulDB Eintrag: 305614 [symisc UnQLite bis 957c377cb691a4f617db9aba5cc46d90425071e2 unqlite.c jx9MemObjStore Pufferüberlauf]
• Punkte: 20