Re: Remaining memory corruption bugs in readline

[Chet Ramey]

On 6/8/17 11:09 AM, dualbus wrote:
> On Fri, Jun 02, 2017 at 12:07:34AM -0500, dualbus wrote:
> [...]
>> #1 _rl_get_char_len / update_line
> [...]
>>   ==5781==ERROR: AddressSanitizer: heap-buffer-overflow on address 
>> 0x61900000cc80 at pc 0x7f400d00b063 bp 0x7ffcbce72250 sp 0x7ffcbce71a00
>>   READ of size 851 at 0x61900000cc80 thread T0
>>       #0 0x7f400d00b062  (/usr/lib/x86_64-linux-gnu/libasan.so.3+0x3c062)
>>       #1 0x559b50a04821 in _rl_get_char_len 
>> ../../../bash/lib/readline/mbutil.c:223
>>       #2 0x559b50a048e0 in _rl_compare_chars 
>> ../../../bash/lib/readline/mbutil.c:252
>>       #3 0x559b509db526 in update_line 
>> ../../../bash/lib/readline/display.c:1664
> [...]
> 
> I have been looking at this specific example for some time now.
> 
> The problem is that _rl_get_char_len assumes it's being called with a
> \0-terminated string, but under some cases (that I haven't been able to
> figure out), there's no \0 at the end, so the strlen reads more than it
> should.

I've been traveling and have not looked at this.

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/