Re: [9fans] sed crash

[Pietro Gagliardi <pietro10@mac.com>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

The bug doesn't seem to be in sed. The match() function calls
rregexec(), which sets a strucuture that is set to loc2, which is made
null for some reason.

On Feb 4, 2009, at 10:08 PM, Pietro Gagliardi wrote:

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> 	lp = loc2;
> 	loc2 = sp - genbuf + linebuf;
> 	while(*sp++ = *lp++)
>
> At the point of crash, loc2 is a null pointer when it is assigned to
> lp, so when the while() statement executes, crash. Now to find out
> why and when loc2 becomes null.
>
> On Feb 4, 2009, at 9:59 PM, Pietro Gagliardi wrote:
>
>> -----BEGIN PGP SIGNED MESSAGE-----
>> Hash: SHA1
>>
>> On Feb 4, 2009, at 9:28 PM, Uriel wrote:
>>
>>> For those that enjoy fixing bugs:
>>>
>>> % echo foo | sed
>>> 's
>>> /..a|..b|..c|..d|..e|..f|..g|..h|..i|..j|..k|..l|..m|..n|..o|..p//g'
>>>
>>> Will crash both native and p9p sed.
>>>
>>> Yes, I know it is a nonsensical expression, but it is the simplest
>>> one
>>> that still made it crash, I have lost the original version which was
>>> much more complex.
>>>
>>> Note that providing two characters as input will still crash, but if
>>> the input line is a single character it wont crash.
>>>
>>> I have been meaning to get all the fun of tracking this one down
>>> myself for a while, but seems that I never get to it, so I will let
>>> others enjoy the fun of fixing it.
>>>
>>> Peace
>>>
>>> uriel
>>>
>> For me, it crashes on the second line of input, in the dosub()
>> function. Will investigate now.
>> -----BEGIN PGP SIGNATURE-----
>> Version: GnuPG v1.4.8 (Darwin)
>>
>> iEYEARECAAYFAkmKVgoACgkQuv7AVNQDs+x7ZACfYvtxSB5c8TD8LFFjPPHsgtah
>> 9DwAnjIQ0GM4b82JGPpdJIUYfHjs7+Pv
>> =7lRk
>> -----END PGP SIGNATURE-----
>>
>
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1.4.8 (Darwin)
>
> iEYEARECAAYFAkmKWCEACgkQuv7AVNQDs+xSQQCgoFPwqMsaphtaKBTHHLFryiJr
> eUMAnA9BjuDpMU40VqJp5hu1EDr3mdXp
> =XF/E
> -----END PGP SIGNATURE-----
>

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.8 (Darwin)

iEUEARECAAYFAkmKYMwACgkQuv7AVNQDs+xcpACYi9wXYM/0ONUOOrqPJu4ViRFZ
BACfTLv0GRuZzUP/WYeU72Jm+KqDunw=
=Vrfb
-----END PGP SIGNATURE-----