fix(modern): check cred field is not NULL before the access

[Andreagit97]

What type of PR is this?

/kind bug

Any specific area of the project related to this PR?

/area driver-modern-bpf

Does this PR require a change in the driver versions?

No

What this PR does / why we need it:

See #2118. Even if this is a possible fix to the issue I don't want to close the issue since we need to investigate more and maybe report it to COS or the upstream kernel if we notice something weird.

Since the bug doesn't depend on us I would suggest fixing it in this way (so we work again on GKE) and report it when we have enough info

Which issue(s) this PR fixes:

See #2118

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[FedeDP]

/approve

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Andreagit97, FedeDP

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• driver/OWNERS [Andreagit97,FedeDP]

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[poiana]

LGTM label has been added.

Git tree hash: 62806b3bb7d2c521b5f2e0574d8eae4cab5483a8

[github-actions]

Perf diff from master - unit tests

     8.85%     +1.90%  [.] sinsp_parser::reset
     8.39%     -1.68%  [.] sinsp::next
     5.62%     -1.27%  [.] sinsp_parser::process_event
     5.84%     -1.09%  [.] sinsp_evt::get_type
     1.59%     +0.68%  [.] sinsp::fetch_next_event
     0.85%     +0.49%  [.] std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_construct<char*>
     0.45%     +0.48%  [.] sinsp_split[abi:cxx11]
     0.74%     -0.42%  [.] sinsp_container_manager::resolve_container
     0.85%     -0.42%  [.] sinsp_fdtable::find
     0.17%     +0.42%  [.] sinsp_threadinfo::sinsp_threadinfo

Heap diff from master - unit tests

peak heap memory consumption: 0B
peak RSS (including heaptrack overhead): 0B
total memory leaked: 0B

Heap diff from master - scap file

peak heap memory consumption: 0B
peak RSS (including heaptrack overhead): 0B
total memory leaked: 0B

Benchmarks diff from master

Comparing gbench_data.json to /root/actions-runner/_work/libs/libs/build/gbench_data.json
Benchmark                                                         Time             CPU      Time Old      Time New       CPU Old       CPU New
----------------------------------------------------------------------------------------------------------------------------------------------
BM_sinsp_split_mean                                            +0.0030         +0.0030           155           155           155           155
BM_sinsp_split_median                                          +0.0105         +0.0105           154           156           154           156
BM_sinsp_split_stddev                                          -0.5096         -0.5098             3             1             3             1
BM_sinsp_split_cv                                              -0.5110         -0.5113             0             0             0             0
BM_sinsp_concatenate_paths_relative_path_mean                  +0.0286         +0.0286            60            62            60            62
BM_sinsp_concatenate_paths_relative_path_median                +0.0260         +0.0260            60            62            60            62
BM_sinsp_concatenate_paths_relative_path_stddev                +2.5630         +2.5656             0             2             0             2
BM_sinsp_concatenate_paths_relative_path_cv                    +2.4638         +2.4664             0             0             0             0
BM_sinsp_concatenate_paths_empty_path_mean                     +0.0117         +0.0117            25            25            25            25
BM_sinsp_concatenate_paths_empty_path_median                   +0.0120         +0.0120            25            25            25            25
BM_sinsp_concatenate_paths_empty_path_stddev                   +1.0090         +1.0104             0             0             0             0
BM_sinsp_concatenate_paths_empty_path_cv                       +0.9858         +0.9871             0             0             0             0
BM_sinsp_concatenate_paths_absolute_path_mean                  +0.0126         +0.0126            62            63            62            63
BM_sinsp_concatenate_paths_absolute_path_median                +0.0025         +0.0025            63            63            63            63
BM_sinsp_concatenate_paths_absolute_path_stddev                -0.8262         -0.8260             1             0             1             0
BM_sinsp_concatenate_paths_absolute_path_cv                    -0.8284         -0.8281             0             0             0             0
BM_sinsp_split_container_image_mean                            +0.0123         +0.0123           391           396           391           396
BM_sinsp_split_container_image_median                          +0.0109         +0.0109           392           396           392           396
BM_sinsp_split_container_image_stddev                          -0.3641         -0.3639             3             2             3             2
BM_sinsp_split_container_image_cv                              -0.3718         -0.3716             0             0             0             0

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 73.69%. Comparing base (c082ec3) to head (615c94a).
Report is 4 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2119   +/-   ##
=======================================
  Coverage   73.69%   73.69%           
=======================================
  Files         253      253           
  Lines       31916    31915    -1     
  Branches     5608     5619   +11     
=======================================
  Hits        23521    23521           
- Misses       8364     8367    +3     
+ Partials       31       27    -4     

Flag	Coverage Δ
libsinsp	73.69% <ø> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[github-actions]

X64 kernel testing matrix

KERNEL	CMAKE-CONFIGURE	KMOD BUILD	KMOD SCAP-OPEN	BPF-PROBE BUILD	BPF-PROBE SCAP-OPEN	MODERN-BPF SCAP-OPEN
amazonlinux2-4.19	🟢	🟢	🟢	🟢	🟢	🟡
amazonlinux2-5.10	🟢	🟢	🟢	🟢	🟢	🟢
amazonlinux2-5.15	🟢	🟢	🟢	🟢	🟢	🟢
amazonlinux2-5.4	🟢	🟢	🟢	🟢	🟢	🟡
amazonlinux2022-5.15	🟢	🟢	🟢	🟢	🟢	🟢
amazonlinux2023-6.1	🟢	🟢	🟢	🟢	🟢	🟢
archlinux-6.0	🟢	🟢	🟢	🟢	🟢	🟢
archlinux-6.7	🟢	🟢	🟢	🟢	🟢	🟢
centos-3.10	🟢	🟢	🟢	🟡	🟡	🟡
centos-4.18	🟢	🟢	🟢	🟢	🟢	🟢
centos-5.14	🟢	🟢	🟢	🟢	🟢	🟢
fedora-5.17	🟢	🟢	🟢	🟢	🟢	🟢
fedora-5.8	🟢	🟢	🟢	🟢	🟢	🟢
fedora-6.2	🟢	🟢	🟢	🟢	🟢	🟢
oraclelinux-3.10	🟢	🟢	🟢	🟡	🟡	🟡
oraclelinux-4.14	🟢	🟢	🟢	🟢	🟢	🟡
oraclelinux-5.15	🟢	🟢	🟢	🟢	🟢	🟢
oraclelinux-5.4	🟢	🟢	🟢	🟢	🟢	🟡
ubuntu-4.15	🟢	🟢	🟢	🟢	🟢	🟡
ubuntu-5.8	🟢	🟢	🟢	🟢	🟢	🟡
ubuntu-6.5	🟢	🟢	🟢	🟢	🟢	🟢

ARM64 kernel testing matrix

KERNEL	CMAKE-CONFIGURE	KMOD BUILD	KMOD SCAP-OPEN	BPF-PROBE BUILD	BPF-PROBE SCAP-OPEN	MODERN-BPF SCAP-OPEN
amazonlinux2-5.4	🟢	🟢	🟢	🟢	🟢	🟡
amazonlinux2022-5.15	🟢	🟢	🟢	🟢	🟢	🟢
fedora-6.2	🟢	🟢	🟢	🟢	🟢	🟢
oraclelinux-4.14	🟢	🟢	🟢	🟡	🟡	🟡
oraclelinux-5.15	🟢	🟢	🟢	🟢	🟢	🟢
ubuntu-6.5	🟢	🟢	🟢	🟢	🟢	🟢

[FedeDP]

/milestone 0.18.2