Subject: b2sum: heap-overflow in digest_check

From: Frank Busse <[email-masked]>
Date: Thu, 22 Jun 2023 17:33:40 +0100

Hi,

KLEE reported a heap-overflow in b2sum (Coreutils 9.3). When running it
with:

$ printf '\n\n0A0BA0' | coreutils-9.3/bin/b2sum -c

(even '0BA0' seems to work on my machine) ASAN confirms the issue:

> #1  0x0000000000473de0 in __interceptor_strchr (s=<optimized out>, c=<optimized out>)
> #2  0x0000000000500a81 in digest_check (checkfile_name=0x7fffffffe69e "stdin") at /tmp/src/coreutils-9.3/src/digest.c:1216
> #3  0x00000000005005e9 in main (argc=3, argv=0x7fffffffe3a8) at /tmp/src/coreutils-9.3/src/digest.c:1607

Best,

Frank