Re: [PATCH] Fix out-of-bouds access (src/common/wchar.c) - Mailing list pgsql-hackers

From Kyotaro Horiguchi
Subject Re: [PATCH] Fix out-of-bouds access (src/common/wchar.c)
Date
Msg-id 20220217.172458.760758446159742763.horikyota.ntt@gmail.com
Whole thread Raw
In response to Re: [PATCH] Fix out-of-bouds access (src/common/wchar.c)  (Julien Rouhaud <rjuju123@gmail.com>)
Responses Re: [PATCH] Fix out-of-bouds access (src/common/wchar.c)  (Julien Rouhaud <rjuju123@gmail.com>)
Re: [PATCH] Fix out-of-bouds access (src/common/wchar.c)  (Ranier Vilela <ranier.vf@gmail.com>)
Re: [PATCH] Fix out-of-bouds access (src/common/wchar.c)  (Ranier Vilela <ranier.vf@gmail.com>)
List pgsql-hackers
At Thu, 17 Feb 2022 15:50:09 +0800, Julien Rouhaud <rjuju123@gmail.com> wrote in 
> On Thu, Feb 17, 2022 at 03:51:26PM +0900, Kyotaro Horiguchi wrote:
> > So, the function doesn't return 63 for all registered names and wrong
> > names.
> > 
> > So other possibilities I can think of are..
> > - Someone had broken pg_encname_tbl[]
> > - Cosmic ray hit, or ill memory cell.
> > - Coverity worked wrong way.
> > 
> > Could you show the workload for the Coverity warning here?
> 
> The 63 upthread was hypothetical right?  pg_encoding_max_length() shouldn't be

I understand that Coverity complaind pg_verify_mbstr_len is fed with
encoding = 63 by length_in_encoding.  I don't know what made Coverity
think so.

> called with user-dependent data (unlike pg_encoding_max_length_sql()), so I
> also don't see any value spending cycles in release builds.  The error should
> only happen with bogus code, and assert builds are there to avoid that, or
> corrupted memory and in that case we can't make any promise.

Well, It's more or less what I wanted to say. Thanks.

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center



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