myxce/.wolf/bugs/bug-1840.md
Rongsong Shen 25d8a461fa
chore: gitea-sync refreshes 23 recent bug issues to the record format
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-09-28 03:44:30 +00:00

3.8 KiB

id status status_updated status_note component severity timestamp last_seen occurrences files tags related repro_attempts legacy gitea_issue gitea_synced_status gitea_synced_hash
bug-1840 cannot-reproduce 2026-09-25 no ASAN repro found. Strongest code-level candidate fixed 2026-09-25: bug-1769 (sched_make_alter_allocation wrote obj1->alloc 136 bytes into a 24-byte heap chunk for any ALTER '{..}||{..}' job -- exactly the kind of out-of-bounds write that corrupts glibc fastbin metadata and surfaces later in an unrelated malloc_consolidate). Reopen to investigating if it recurs, ideally captured on an ASAN build. scheduler crash 2026-09-22T02:35:00Z 2026-09-22T02:35:00Z 1
unknown -- heap corruption detected far from its cause
scheduler
heap-corruption
malloc-consolidate
netio
ssl-handshake
live-crash
user-reported
needs-asan-repro
needs-diagnosis
bug-1839
0/1 ASAN run, 2026-09-25: 3-node HA + worker + scheduler, 8 waves x 6 concurrent 'jobsub -a 50' (2400 elements) on the current ASAN build -- no AddressSanitizer report from the scheduler; plus ~10 ASAN HA soaks today (sequential/chaotic, all with scheduler replay-verify) with no scheduler heap error true 74 cannot-reproduce 0bf94f05143e

bug-1840: Live 3-node HA cluster crash (same soak run as bug-1839): xce_scheduler SIGABRT, glibc…

Description

Live 3-node HA cluster crash (same soak run as bug-1839): xce_scheduler SIGABRT, glibc malloc_consolidate(): unaligned fastbin chunk detected, surfacing during an OpenSSL TLS handshake's MAC-buffer growth: abort -> malloc_printerr -> malloc_consolidate -> _int_malloc -> __libc_malloc2 -> CRYPTO_malloc -> CRYPTO_clear_realloc -> BUF_MEM_grow_clean -> mem_write -> bwrite_conv -> BIO_write -> ssl3_finish_mac -> tls_get_message_body -> state_machine -> handle_ssl_handshake (netio.c:548) -> io_handler (netio.c:588) -> io_worker_dispatch_batch (netio.c:648) -> io_worker (netio.c:689).

Environment

Not recorded (migrated from buglog.json).

Reproduction

  • Attempts: 0/1 ASAN run, 2026-09-25: 3-node HA + worker + scheduler, 8 waves x 6 concurrent 'jobsub -a 50' (2400 elements) on the current ASAN build -- no AddressSanitizer report from the scheduler; plus ~10 ASAN HA soaks today (sequential/chaotic, all with scheduler replay-verify) with no scheduler heap error

Root cause

NOT YET DIAGNOSED -- heap corruption detected far from its cause; a corrupted fastbin chunk was only found during an unrelated later malloc_consolidate() call, inside an OpenSSL TLS handshake on the scheduler's io_worker thread. The actual out-of-bounds write that corrupted the allocator's freelist could have happened in any thread, any amount of time earlier, and is not reconstructable from a non-ASAN build.dbg core dump -- there is no shadow memory, no poisoning, nothing to localize it to a specific allocation or write site. Confirmed directly via gdb against the real core file (/tmp/core.xce_scheduler, build cd9ecb41): the crashing frames' locals (malloc_consolidate's av/fb/p) are all optimized out / no debug symbols available for glibc or libcrypto/libssl in this environment, so there is nothing further to extract from the core itself beyond the symbol-only backtrace already captured. Needs an ASAN reproduction of the same 3-node HA deploy soak scenario to catch the actual out-of-bounds write with a real stack trace.

Fix

NOT FIXED -- awaiting an ASAN repro. Recommended next step: /xce-build scheduler asan (or bash src/tools/xce-build.sh scheduler asan), then rerun the same HA deploy scenario that produced /tmp/core.xce_scheduler until ASAN aborts at the real corruption site, which will pinpoint the actual overflow/write instead of just its downstream symptom.

Verification

Not recorded (migrated from buglog.json).

References

  • Related: bug-1839
  • Gitea: #74