Thread: Re: [PATCH] snowball: fix potential NULL dereference

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<m.korotkov@postgrespro.ru>writes: 
> I found the case of potential NULL pointer dereference.
> In snowball/libstemmer/api.c if we transfer control to the SN_create_env() function
> by using the error label when there is a memory allocation error of z->p or z->S,
> we can then dereference the NULL pointer z->S in the function SN_close_env().
> Added the pointer check for avoiding a potential problem.

I believe you are right: OOM partway through SN_create_env would fail.
However, backend/snowball is not our code so applying our own local
patch is not the way to fix it.  You should report this upstream;
see src/backend/snowball/README.

(Whenever they apply the patch, we should then re-sync...)

            regards, tom lane

Hi
On 2025-02-11 19:53, Tom Lane wrote:
> You should report this upstream;
> (Whenever they apply the patch, we should then re-sync...)

FYI, the patch to fix this problem was applied by upstream.
---
Best regards, Korotkov Maksim
PostgresPro
m.korotkov@postgrespro.ru

Maksim Korotkov <m.korotkov@postgrespro.ru> writes:
> On 2025-02-11 19:53, Tom Lane wrote:
>> You should report this upstream;
>> (Whenever they apply the patch, we should then re-sync...)

> FYI, the patch to fix this problem was applied by upstream.

Thanks.  Barring objections, I'll do a full resync per
src/backend/snowball/README on HEAD, and then extract just
the null-dereference fix to apply to our back branches.

            regards, tom lane