Fix some potential null derefs

[N-R-K]

These got caught by trying to compile with LTO enabled.

There were a couple more, which I'm not sure what to do with. Opened a PR just so other's who are interested can take a look as well: #233

[rkta]

Instead of checking for NULL after every newBuffer call I suggest to exit if malloc fails. Exiting is a pattern that is used in many places already. Also, in the very unlikely case that malloc fails, there is not much we can do.

See my patch here: https://git.sr.ht/~rkta/w3m/commit/1f88544c1a009ed2088ff20973bcfffe6cbcb5de

@N-R-K what do you think?

[N-R-K]

Instead of checking for NULL after every newBuffer call I suggest to exit if malloc fails. Exiting is a pattern that is used in many places already. Also, in the very unlikely case that malloc fails, there is not much we can do.

See my patch here: https://git.sr.ht/~rkta/w3m/commit/1f88544c1a009ed2088ff20973bcfffe6cbcb5de

@N-R-K what do you think?

That would be my preference as well - but I wasn't sure if that's acceptable upstream or not since there are a couple places where allocation failure results in showing an error msg but not exiting.

About your patch - I'd print some diagnostic to stderr as well - perhaps with perror().

[rkta]

On Sun, Nov 27, 2022 at 04:10:47AM -0800, N-R-K wrote: > Instead of checking for NULL after every newBuffer call I suggest to exit if malloc fails. Exiting is a pattern that is used in many places already. Also, in the very unlikely case that malloc fails, there is not much we can do. > > See my patch here: https://git.sr.ht/~rkta/w3m/commit/1f88544c1a009ed2088ff20973bcfffe6cbcb5de > > @N-R-K what do you think? That would be my preference as well - but I wasn't sure if that's acceptable upstream or not since there are a couple places where allocation failure results in showing an error msg but not exiting.

Then let's wait for upstream.

About your patch - I'd print some diagnostic to `stderr` as well - perhaps with `perror()`.

I was not sure if the message will be readable after w3m exits. That's why I exit with. Idea was to use a special value for malloc failures. Gotta test if perror() will work. But given how unlikely a malloc failure is, I put it low on my TODO list. :)

[tats]

@rkta

See my patch here: https://git.sr.ht/~rkta/w3m/commit/1f88544c1a009ed2088ff20973bcfffe6cbcb5de

For now, I've applied your patch for newBuffer() to exit with error.

allocStr() seems already done.

Thanks for your contribution.

[N-R-K]

For now, I've applied your patch for newBuffer() to exit with error.

IMO it was the right decision. It's better to fix the source of the problem than to fix the call-sites!