[bp/1.35] compat/openssl: Ensure OpenSSL uses tcmalloc functions - #596
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tedjpoole wants to merge 1 commit into
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[bp/1.35] compat/openssl: Ensure OpenSSL uses tcmalloc functions#596tedjpoole wants to merge 1 commit into
tedjpoole wants to merge 1 commit into
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When dynamically loading the OpenSSL shared libraries, we use the RTLD_DEEPBIND option so that the compatibility layer's wrapper symbols don't shadow the real OpenSSL ones. As an unintended consequence of this, it causes OpenSSL's calls to malloc/realloc/free to bind to glibc's allocator instead of the tcmalloc that is statically linked into Envoy. The result is that OpenSSL operates on a completely separate heap, defeating tcmalloc's performance benefits on the TLS hot path and making all OpenSSL allocations invisible to tcmalloc heap profiling and memory dumps. This is fixed by calling CRYPTO_set_mem_functions() immediately after loading libcrypto.so, thus redirecting OpenSSL's malloc/realloc/free calls to the main executable's tcmalloc functions. Also added a test to verify that OpenSSL is using allocator functions that reside in the main executable (tcmalloc) rather than inside `libcrypto.so` (glibc via `RTLD_DEEPBIND`), preventing regressions. Backport of envoyproxy/envoy#46562 & envoyproxy/envoy#46576 Signed-off-by: Ted Poole <tpoole@redhat.com> Signed-off-by: Jonh Wendell <jwendell@redhat.com> Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
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When dynamically loading the OpenSSL shared libraries, we use the RTLD_DEEPBIND option so that the compatibility layer's wrapper symbols don't shadow the real OpenSSL ones. As an unintended consequence of this, it causes OpenSSL's calls to malloc/realloc/free to bind to glibc's allocator instead of the tcmalloc that is statically linked into Envoy.
The result is that OpenSSL operates on a completely separate heap, defeating tcmalloc's performance benefits on the TLS hot path and making all OpenSSL allocations invisible to tcmalloc heap profiling and memory dumps.
This is fixed by calling CRYPTO_set_mem_functions() immediately after loading libcrypto.so, thus redirecting OpenSSL's malloc/realloc/free calls to the main executable's tcmalloc functions.
Also added a test to verify that OpenSSL is using allocator functions that reside in the main executable (tcmalloc) rather than inside
libcrypto.so(glibc viaRTLD_DEEPBIND), preventing regressions.Backport of envoyproxy/envoy#46562 & envoyproxy/envoy#46576