feat(cef): LD_PRELOAD mallinfo shim to fix MemoryInfra SIGILL#508
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feat(cef): LD_PRELOAD mallinfo shim to fix MemoryInfra SIGILL#508
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…e CEF 144 The MemoryInfra SIGILL is an int overflow in libcef.so's call to glibc's legacy int-based mallinfo(). Spotify's official CEF builds compile against a Debian bullseye sysroot (glibc 2.31) which lacks mallinfo2, so the int API is baked in. When the CEF process arena exceeds 2 GiB, the int fields overflow to negative, Chromium checked_cast<size_t> them, the narrowing check fails, and Chromium CHECKs -> SIGILL. This is the real root cause, identified in CEF issue #3963 and upstream Chromium bug 401168177. It is not a Chrome-runtime regression — Chrome runtime just makes it more visible through more long-lived allocations. Fix: LD_PRELOAD a small shim that interposes mallinfo() and returns zeros. Chromium narrows 0 to size_t without overflow; the memory dump records zero bytes for the CEF process (we don't use MemoryInfra in production). Workaround confirmed by another user on #3963. - docker/gstcefsrc/mallinfo_shim.c: new shim source (~30 lines of C). - docker/gstcefsrc/Dockerfile: compile shim to libmallinfo_shim.so during build, ship in output tarball. Restore CEF 144.0.11 and pin gstcefsrc master HEAD (b63340852f) — the shim removes the reason to downgrade. - .github/workflows/build-gstcefsrc.yml: update defaults to CEF 144 and current gstcefsrc master. - docker/strom-full/entrypoint.sh: LD_PRELOAD the shim before exec. - docs/CEF_SIGILL_CRASH.md: document the real bug and the shim-based fix; explain why downgrading is no longer needed. Safety: the shim only replaces the mallinfo() symbol; all allocator entry points (malloc/free/calloc/realloc) are untouched. GStreamer, GLib, Rust's allocator, and our own code do not call mallinfo(). The only consumer in our process tree is Chromium's MemoryInfra thread — which is exactly what we want to silence. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
mallinfo(); when the CEF arena exceeds 2 GiB the int fields overflow, Chromiumchecked_cast<size_t>fails, and Chromium CHECKs → SIGILL.mallinfo()with a zero-filled struct. No overflow, no crash, and zero impact on GStreamer/GLib/Rust (nothing in our stack callsmallinfo).Test plan
build-gstcefsrc.ymlsucceeds for both linux-amd64 and linux-arm64gstcefsrc-144.0.11-linux-*.tar.gzcontainslib/cef/libmallinfo_shim.sostrom-fullruns withLD_PRELOADset; cefsrc flows run without SIGILL beyond 2 GiB arena usage