apcsmart driver "nument or entlen out of range" when connecting

[eimparas]

apcsmart driver "nument or entlen out of range" when connecting

[jimklimov]

That rings a bell a bit, at least the driver was recently discussed. Not on PC now - can you please search issues for apcsmart?

Not sure if this driver was addressed by code changes after 2.8.0 release, but it's always worth trying a custom build of current NUT to know if the issue still needs solving :} Wiki has an article on "in-place" build configs to have a custom build configured similarly to your packaged one; a driver test run can be done from a build workspace without impacting the OS.

Also, can you try starting the driver binary with debug options (wiki suggests some ways) to help pinpoint where/why it gets that "bad" data.

[jimklimov]

So, dug a bit into code history - the message originates from beb4b54

So before this fix, the code went:
https://github.com/networkupstools/nut/blame/cbfe9ab178183a85a216fd8f789895d786d3055c/drivers/apcsmart.c#L1019-L1023

...and might end up with negative nument and/or entlen. Which, looking a bit more at the rest of code, would make the rest of the cycle no-op. Probably bailing out was too harsh here, reporting and ignoring (going to next loop) may be the proper approach after all.

[jimklimov]

CC @aquette as the initial committer (though I guess it is further shrouded in SVN history), and @msoltyspl.

[jimklimov]

Posted a PR - if you have a chance to build and test that branch, would be great!