[UBSAN] Fix runtime error about variable length array bound

[smuzaffar]

This should fix the ubsan errors of type [a]. SiStripFedZeroSuppression::suppress(...) does not do much for inSize=0.

[a] https://cmssdt.cern.ch/SDT/jenkins-artifacts/ubsan_logs/CMSSW_13_2_X_2023-06-02-2300/logs/50/5072528821a0b4b2f766743a9c79dd0d/log

10001.0/step2:RecoLocalTracker/SiStripZeroSuppression/src/SiStripFedZeroSuppression.cc:95:22: runtime error: variable length array bound evaluates to non-positive value 0
10002.0/step2:RecoLocalTracker/SiStripZeroSuppression/src/SiStripFedZeroSuppression.cc:95:22: runtime error: variable length array bound evaluates to non-positive value 0
10003.0/step2:RecoLocalTracker/SiStripZeroSuppression/src/SiStripFedZeroSuppression.cc:95:22: runtime error: variable length array bound evaluates to non-positive value 0
10004.0/step2:RecoLocalTracker/SiStripZeroSuppression/src/SiStripFedZeroSuppression.cc:95:22: runtime error: variable length array bound evaluates to non-positive value 0

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-41881/35802

• This PR adds an extra 16KB to repository

[cmsbuild]

A new Pull Request was created by @smuzaffar (Malik Shahzad Muzaffar) for master.

It involves the following packages:

• RecoLocalTracker/SiStripZeroSuppression (reconstruction)

@cmsbuild, @mandrenguyen, @clacaputo can you please review it and eventually sign? Thanks.
@echabert, @VourMa, @gbenelli, @missirol, @GiacomoSguazzoni, @yduhm, @robervalwalsh, @JanFSchulte, @rovere, @VinInn, @alesaggio, @felicepantaleo, @mtosi, @gpetruc, @mmusich, @threus, @jlidrych this is something you requested to watch as well.
@perrotta, @dpiparo, @rappoccio you are the release manager for this.

cms-bot commands are listed here

[VinInn]

why changing it to size_t?

[smuzaffar]

It was not needed to fix the UBSAN error but thought that as inSize is >=0 ( std::vector::size() returns size_t ... rigth) that is why I converted it to size_t and then update loop index i to be of same type and avoid extra arithmetic [a]

[a]

RecoLocalTracker/SiStripZeroSuppression/src/SiStripFedZeroSuppression.cc:144:22: error: comparison of unsigned expression in '>= 0' is always true [-Werror=type-limits]
  144 |     } else if (i - 1 >= 0 && in[i - 1].strip() == strip - 1) {
      |                ~~~~~~^~~~
RecoLocalTracker/SiStripZeroSuppression/src/SiStripFedZeroSuppression.cc:148:24: error: comparison of unsigned expression in '>= 0' is always true [-Werror=type-limits]
  148 |       } else if (i - 2 >= 0 && in[i - 2].strip() == strip - 2) {
      |                  ~~~~~~^~~~

[smuzaffar]

please test

[cmsbuild]

+1

Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-240b3e/33010/summary.html
COMMIT: 5be700a
CMSSW: CMSSW_13_2_X_2023-06-06-1100/el8_amd64_gcc11
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week0/cms-sw/cmssw/41881/33010/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• You potentially added 18 lines to the logs
• Reco comparison results: 5 differences found in the comparisons
• DQMHistoTests: Total files compared: 48
• DQMHistoTests: Total histograms compared: 3219909
• DQMHistoTests: Total failures: 6
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 3219881
• DQMHistoTests: Total skipped: 22
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 47 files compared)
• Checked 207 log files, 159 edm output root files, 48 DQM output files
• TriggerResults: no differences found

[mandrenguyen]

+1

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next master IBs (tests are also fine). This pull request will now be reviewed by the release team before it's merged. @perrotta, @dpiparo, @rappoccio (and backports should be raised in the release meeting by the corresponding L2)

[perrotta]

+1