Re: Don't pass NULL pointer to strcmp().

Looking closer, I realized that my proposed change in RestoreGUCState is unnecessary, because guc_free() is already permissive about being passed a NULL. That leaves us with one live bug in get_explain_guc_options, two probably-unreachable hazards in check_GUC_init and write_one_nondefault_variabl

Re: Don't pass NULL pointer to strcmp().

Hi, Seems that Tom's patch cannot be applied to the current master branch. I just re-generate the patch for others to play with. On 11/2/23, Nathan Bossart wrote: > On Wed, Nov 01, 2023 at 10:39:04PM -0400, Tom Lane wrote: >> Nathan Bossart writes: >>> What if we disallowed NULL string GUCs in

Re: Don't pass NULL pointer to strcmp().

On Wed, Nov 01, 2023 at 10:39:04PM -0400, Tom Lane wrote: > Nathan Bossart writes: >> What if we disallowed NULL string GUCs in v17? > > Well, we'd need to devise some other solution for hacks like the > one used by timezone_abbreviations (see comment in > check_timezone_abbreviations). I think

Re: Don't pass NULL pointer to strcmp().

Nathan Bossart writes: > On Wed, Nov 01, 2023 at 09:57:18PM -0400, Tom Lane wrote: >> After digging around for a bit, I think part of the problem is a lack >> of a clearly defined spec for what should happen with NULL string GUCs. > What if we disallowed NULL string GUCs in v17? Well, we'd need

Re: Don't pass NULL pointer to strcmp().

On Wed, Nov 01, 2023 at 09:57:18PM -0400, Tom Lane wrote: > I wrote: >> Hmm ... if we're doing it ourselves, I suppose we've got to consider >> it supported :-(. But I'm still wondering how many seldom-used >> code paths didn't get the message. An example here is that this >> could lead to GetCon

Re: Don't pass NULL pointer to strcmp().

Thank you Tom! Your comment "NULL doesn't have semantics that are visibly different from an empty string" is exactly what I want to confirm :-) On 11/2/23, Tom Lane wrote: > I wrote: >> Hmm ... if we're doing it ourselves, I suppose we've got to consider >> it supported :-(. But I'm still wonde

Re: Don't pass NULL pointer to strcmp().

I wrote: > Hmm ... if we're doing it ourselves, I suppose we've got to consider > it supported :-(. But I'm still wondering how many seldom-used > code paths didn't get the message. An example here is that this > could lead to GetConfigOptionResetString returning NULL, which > I think is outside

Re: Don't pass NULL pointer to strcmp().

Xing Guo writes: > There're extensions that set their boot_val to NULL. E.g., postgres_fdw Hmm ... if we're doing it ourselves, I suppose we've got to consider it supported :-(. But I'm still wondering how many seldom-used code paths didn't get the message. An example here is that this could le

Re: Don't pass NULL pointer to strcmp().

Hi Tom, There're extensions that set their boot_val to NULL. E.g., postgres_fdw ( https://github.com/postgres/postgres/blob/4210b55f598534db9d52c4535b7dcc777dda75a6/contrib/postgres_fdw/option.c#L582), plperl ( https://github.com/postgres/postgres/blob/4210b55f598534db9d52c4535b7dcc777dda75a6/src/

Re: Don't pass NULL pointer to strcmp().

Xing Guo writes: > Thanks for your comments. I have updated the patch accordingly. I'm leery of accepting this patch, as I see no reason that we should consider it valid for an extension to have a string GUC with a boot_val of NULL. I realize that we have a few core GUCs that are like that, but

Re: Don't pass NULL pointer to strcmp().

Hi Aleksander and Junwang, Thanks for your comments. I have updated the patch accordingly. Best Regards, Xing On Wed, Nov 1, 2023 at 7:44 PM Aleksander Alekseev wrote: > Hi, > > > > I found that there's a nullable pointer being passed to strcmp() and > > > can make the server crash. It

Re: Don't pass NULL pointer to strcmp().

Hi, > > I found that there's a nullable pointer being passed to strcmp() and > > can make the server crash. It can be reproduced on the latest master > > branch by crafting an extension[1]. Patch for fixing it is attatched. > > > > [1] https://github.com/higuoxing/guc_crash/tree/pg Thanks for rep

Re: Don't pass NULL pointer to strcmp().

On Wed, Nov 1, 2023 at 5:25 PM Xing Guo wrote: > > Hi hackers, > > I found that there's a nullable pointer being passed to strcmp() and > can make the server crash. It can be reproduced on the latest master > branch by crafting an extension[1]. Patch for fixing it is attatched. > > [1] https://git

Don't pass NULL pointer to strcmp().

Hi hackers, I found that there's a nullable pointer being passed to strcmp() and can make the server crash. It can be reproduced on the latest master branch by crafting an extension[1]. Patch for fixing it is attatched. [1] https://github.com/higuoxing/guc_crash/tree/pg -- Best Regards, Xing Fr