gitlab: add lsan suppression file to workaround tcmalloc issues

The up-coming upgrade to Fedora 37 will bring in libtcmalloc as a
dependency of libglusterfs which confuses our fuzz run. Rather than
disable the build lets use LSAN's suppression mechanism to prevent the
job from failing.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Cc: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230124180127.1881110-10-alex.bennee@linaro.org>

.gitlab-ci.d/buildtest.yml

@@ -511,6 +511,7 @@ build-oss-fuzz:
     IMAGE: fedora
   script:
     - mkdir build-oss-fuzz
+    - export LSAN_OPTIONS=suppressions=scripts/oss-fuzz/lsan_suppressions.txt
     - CC="clang" CXX="clang++" CFLAGS="-fsanitize=address"
       ./scripts/oss-fuzz/build.sh
     - export ASAN_OPTIONS="fast_unwind_on_malloc=0"

scripts/oss-fuzz/lsan_suppressions.txt

@@ -0,0 +1,2 @@
+# The tcmalloc on Fedora37 confuses things
+leak:/lib64/libtcmalloc_minimal.so.4