fix(userspace/libsinsp): stringop-overflow on libvirt_lxc

[deepskyblue86]

What type of PR is this?
/kind bug

Any specific area of the project related to this PR?

/area libsinsp

Does this PR require a change in the driver versions?

What this PR does / why we need it:

Building with Red Hat g++ 11.2.1-9 we get the following error on string assignment:

[ 34%] Building CXX object libsinsp/CMakeFiles/sinsp.dir/container_engine/libvirt_lxc.cpp.o
In file included from /opt/rh/devtoolset-11/root/usr/include/c++/11/ios:40,
                 from /opt/rh/devtoolset-11/root/usr/include/c++/11/ostream:38,
                 from /opt/rh/devtoolset-11/root/usr/include/c++/11/bits/unique_ptr.h:42,
                 from /opt/rh/devtoolset-11/root/usr/include/c++/11/memory:76,
                 from /code/agent/deps/agent-libs/userspace/libsinsp/container_engine/container_engine_base.h:21,
                 from /code/agent/deps/agent-libs/userspace/libsinsp/container_engine/libvirt_lxc.h:24,
                 from /code/agent/deps/agent-libs/userspace/libsinsp/container_engine/libvirt_lxc.cpp:19:
In static member function 'static constexpr std::char_traits<char>::char_type* std::char_traits<char>::copy(std::char_traits<char>::char_type*, const char_type*, std::size_t)',
    inlined from 'static void std::basic_string<_CharT, _Traits, _Alloc>::_M_copy(_CharT*, const _CharT*, std::basic_string<_CharT, _Traits, _Alloc>::size_type) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]' at /opt/rh/devtoolset-11/root/usr/include/c++/11/bits/basic_string.h:3464:21,
    inlined from 'std::basic_string<_CharT, _Traits, _Allocator>& std::basic_string<_CharT, _Traits, _Alloc>::assign(const _CharT*, std::basic_string<_CharT, _Traits, _Alloc>::size_type) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]' at /opt/rh/devtoolset-11/root/usr/include/c++/11/bits/basic_string.tcc:701:13,
    inlined from 'std::basic_string<_CharT, _Traits, _Allocator>& std::basic_string<_CharT, _Traits, _Alloc>::assign(const _CharT*, std::basic_string<_CharT, _Traits, _Alloc>::size_type) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]' at /opt/rh/devtoolset-11/root/usr/include/c++/11/bits/basic_string.tcc:689:5,
    inlined from 'std::basic_string<_CharT, _Traits, _Alloc>& std::basic_string<_CharT, _Traits, _Alloc>::assign(const _CharT*) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]' at /opt/rh/devtoolset-11/root/usr/include/c++/11/bits/basic_string.h:4461:21,
    inlined from 'std::basic_string<_CharT, _Traits, _Alloc>& std::basic_string<_CharT, _Traits, _Alloc>::operator=(const _CharT*) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]' at /opt/rh/devtoolset-11/root/usr/include/c++/11/bits/basic_string.h:3784:28,
    inlined from 'bool libsinsp::container_engine::libvirt_lxc::match(sinsp_threadinfo*, sinsp_container_info&)' at /code/agent/deps/agent-libs/userspace/libsinsp/container_engine/libvirt_lxc.cpp:51:17:
/opt/rh/devtoolset-11/root/usr/include/c++/11/bits/char_traits.h:437:56: error: 'void* __builtin_memcpy(void*, const void*, long unsigned int)' writing 14 bytes into a region of size 7 overflows the destination [-Werror=stringop-overflow=]
  437 |         return static_cast<char_type*>(__builtin_memcpy(__s1, __s2, __n));
      |                                        ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~

Let's just do a single assignment, and avoid eventual resize.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[poiana]

LGTM label has been added.

Git tree hash: 842e280311388b9580f641a3a9f2eef7ff9d97bf

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 3 lines in your changes missing coverage. Please review.

Project coverage is 73.70%. Comparing base (c082ec3) to head (c0d8766).
Report is 3 commits behind head on master.

Files with missing lines	Patch %	Lines
...serspace/libsinsp/container_engine/libvirt_lxc.cpp	0.00%	3 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2115   +/-   ##
=======================================
  Coverage   73.69%   73.70%           
=======================================
  Files         253      253           
  Lines       31916    31915    -1     
  Branches     5608     5627   +19     
=======================================
+ Hits        23521    23522    +1     
- Misses       8364     8387   +23     
+ Partials       31        6   -25     

Flag	Coverage Δ
libsinsp	73.70% <0.00%> (+<0.01%)	⬆️

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

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[github-actions]

Perf diff from master - unit tests

     3.40%     -0.97%  [.] sinsp_thread_manager::find_thread
     3.89%     +0.90%  [.] sinsp_evt::load_params
     8.96%     +0.89%  [.] sinsp_parser::reset
     1.56%     +0.83%  [.] scap_event_decode_params
     4.94%     -0.74%  [.] sinsp_parser::process_event
     1.00%     -0.56%  [.] sinsp_fdtable::find
     1.50%     -0.55%  [.] sinsp_threadinfo::~sinsp_threadinfo
     1.56%     -0.51%  [.] sinsp_evt::get_ts
     0.22%     +0.51%  [.] std::_Hashtable<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, libsinsp::state::dynamic_struct::field_info>, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, libsinsp::state::dynamic_struct::field_info> >, std::__detail::_Select1st, std::equal_to<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::hash<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, false, true> >::_M_emplace<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, libsinsp::state::dynamic_struct::field_info> >
     7.95%     -0.50%  [.] sinsp::next

Heap diff from master - unit tests

peak heap memory consumption: -5.18K
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                                            +0.0315         +0.0317           147           152           147           152
BM_sinsp_split_median                                          +0.0285         +0.0286           148           152           148           152
BM_sinsp_split_stddev                                          -0.0747         -0.0747             1             1             1             1
BM_sinsp_split_cv                                              -0.1030         -0.1032             0             0             0             0
BM_sinsp_concatenate_paths_relative_path_mean                  +0.1051         +0.1052            56            61            56            61
BM_sinsp_concatenate_paths_relative_path_median                +0.0946         +0.0948            56            61            56            61
BM_sinsp_concatenate_paths_relative_path_stddev                -0.8957         -0.8952             1             0             1             0
BM_sinsp_concatenate_paths_relative_path_cv                    -0.9056         -0.9052             0             0             0             0
BM_sinsp_concatenate_paths_empty_path_mean                     +0.0146         +0.0148            25            25            25            25
BM_sinsp_concatenate_paths_empty_path_median                   +0.0117         +0.0120            24            25            24            25
BM_sinsp_concatenate_paths_empty_path_stddev                   +0.4113         +0.4088             0             0             0             0
BM_sinsp_concatenate_paths_empty_path_cv                       +0.3909         +0.3883             0             0             0             0
BM_sinsp_concatenate_paths_absolute_path_mean                  +0.0943         +0.0943            56            61            56            61
BM_sinsp_concatenate_paths_absolute_path_median                +0.0662         +0.0662            56            59            56            59
BM_sinsp_concatenate_paths_absolute_path_stddev                +5.6010         +5.6086             0             2             0             2
BM_sinsp_concatenate_paths_absolute_path_cv                    +5.0321         +5.0391             0             0             0             0
BM_sinsp_split_container_image_mean                            +0.0008         +0.0008           391           391           391           391
BM_sinsp_split_container_image_median                          -0.0022         -0.0023           391           390           391           390
BM_sinsp_split_container_image_stddev                          +1.3500         +1.3512             1             3             1             3
BM_sinsp_split_container_image_cv                              +1.3480         +1.3493             0             0             0             0

[FedeDP]

Great catch, thanks for the fix!
/approve

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: deepskyblue86, FedeDP

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

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• OWNERS [FedeDP]

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[FedeDP]

/milestone 0.19.0