fix(userspace/libsinsp): fixed possible buffer overflow in sinsp_plugin::get_metrics

[FedeDP]

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:

This PR fixes a possible source of buffer overflow in the recently-added sinsp_plugin::get_metrics API (#1828).

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Output on master:

[ RUN      ] sinsp_with_test_input.plugin_metrics
*** buffer overflow detected ***: terminated
Annullato (core dump creato)

Full trace (courtesy of valgrind massif (?)):

[ RUN      ] sinsp_with_test_input.plugin_metrics
*** buffer overflow detected ***: terminated
==311913== 
==311913== Process terminating with default action of signal 6 (SIGABRT)
==311913==    at 0x5215B1C: __pthread_kill_implementation (pthread_kill.c:44)
==311913==    by 0x5215B1C: __pthread_kill_internal (pthread_kill.c:78)
==311913==    by 0x5215B1C: pthread_kill@@GLIBC_2.34 (pthread_kill.c:89)
==311913==    by 0x51BC26D: raise (raise.c:26)
==311913==    by 0x519F8FE: abort (abort.c:79)
==311913==    by 0x51A07B5: __libc_message_impl.cold (libc_fatal.c:132)
==311913==    by 0x52ADC18: __fortify_fail (fortify_fail.c:24)
==311913==    by 0x52AD5D3: __chk_fail (chk_fail.c:28)
==311913==    by 0x52AF018: __strlcpy_chk (strlcpy_chk.c:28)
==311913==    by 0x7312C2: strlcpy (string_fortified.h:156)
==311913==    by 0x7312C2: sinsp_plugin::get_metrics() const (plugin.cpp:944)
==311913==    by 0x72B1EB: libs::metrics::libs_metrics_collector::snapshot() (metrics_collector.cpp:468)
==311913==    by 0x46F515: sinsp_with_test_input_plugin_metrics_Test::TestBody() (plugins.ut.cpp:909)
==311913==    by 0x8B6DEE: void testing::internal::HandleExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) (in /home/federico/Work/libs/build/libsinsp/test/unit-test-libsinsp)
==311913==    by 0x89EB15: testing::Test::Run() (in /home/federico/Work/libs/build/libsinsp/test/unit-test-libsinsp)
==311913==    by 0x89ECD4: testing::TestInfo::Run() (in /home/federico/Work/libs/build/libsinsp/test/unit-test-libsinsp)
==311913==    by 0x89EEBE: testing::TestSuite::Run() (in /home/federico/Work/libs/build/libsinsp/test/unit-test-libsinsp)
==311913==    by 0x8ACD2B: testing::internal::UnitTestImpl::RunAllTests() (in /home/federico/Work/libs/build/libsinsp/test/unit-test-libsinsp)
==311913==    by 0x8B74C6: bool testing::internal::HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) (in /home/federico/Work/libs/build/libsinsp/test/unit-test-libsinsp)
==311913==    by 0x89F0B7: testing::UnitTest::Run() (in /home/federico/Work/libs/build/libsinsp/test/unit-test-libsinsp)
==311913==    by 0x2C0143: main (in /home/federico/Work/libs/build/libsinsp/test/unit-test-libsinsp)
==311913== 
Annullato (core dump creato)

Does this PR introduce a user-facing change?:

fix(userspace/libsinsp): fixed possible buffer overflow in sinsp_plugin::get_metrics

/milestone 0.17.1

[Molter73]

/lgtm

Nice catch!

[FedeDP]

/hold

[FedeDP]

/cc @LucaGuerra

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: FedeDP, LucaGuerra, Molter73

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• OWNERS [FedeDP,LucaGuerra,Molter73]

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[FedeDP]

/unhold