Memory corruption issues #2280
Description
What happened?
We're building a new service on top of FrankenPHP.
Around the time of the 1.11.2 security update, we realized that our containers have been crashing at irregular intervals, and the various logging messages indicated some kind of low level memory corruption. At the time we were upgrading from 1.9.0 and similar memory corruption logs were being logged from the previous version.
The various error messages we were seeing include:
- malloc_consolidate(): unaligned fastbin chunk detected
- Out of memory
- zend_mm_heap corrupted
- malloc(): unaligned tcache chunk detected
- memory allocation of [3275089422124871200-8245929725132762100] bytes failed
- double free or corruption (fasttop)
We also noticed that some logs seemed to have been interleaved as well:
- memory allocation of memory allocation of [78096346336516770000000000000000000000-78817066060829420000000000000000000000] bytes failed
- bytes failed
- 7881706606082942000 bytes failed
Our app is still fairly new and does not currently deal with a heavy amount of traffic, but we've been unable to determine a direct cause for the conditions leading up to these memory corruption related crashes. We've tried disabling Datadog's tracing and profiling as well as disabling opcache, but these crashes seem to persist.
Crashes seem to vary pretty wildly in frequency, a 12 hour period having between roughly 0-20 crashes (the extreme ends being less common), with no noticeable correlation to time of day/week.
Build Type
Docker (Debian Trixie)
Worker Mode
No
Operating System
GNU/Linux
CPU Architecture
x86_64
PHP configuration
phpinfo() output
System Linux 6.12.68-92.122.amzn2023.x86_64 #1 SMP PREEMPT_DYNAMIC Mon Feb 9 10:43:10 UTC 2026 x86_64
Build Date Feb 3 2026 02:28:00
Build System Linux - Docker
Build Provider https://github.com/docker-library/php
Configure Command './configure' '--build=x86_64-linux-gnu' '--sysconfdir=/usr/local/etc' '--with-config-file-path=/usr/local/etc/php' '--with-config-file-scan-dir=/usr/local/etc/php/conf.d' '--enable-option-checking=fatal' '--with-mhash' '--with-pic' '--enable-mbstring' '--enable-mysqlnd' '--with-password-argon2' '--with-sodium=shared' '--with-pdo-sqlite=/usr' '--with-sqlite3=/usr' '--with-curl' '--with-iconv' '--with-openssl' '--with-readline' '--with-zlib' '--enable-phpdbg' '--enable-phpdbg-readline' '--with-pear' '--with-libdir=lib/x86_64-linux-gnu' '--enable-embed' '--enable-zts' '--disable-zend-signals' 'build_alias=x86_64-linux-gnu' 'PHP_UNAME=Linux - Docker' 'PHP_BUILD_PROVIDER=https://github.com/docker-library/php'
Server API FrankenPHP
Virtual Directory Support enabled
Configuration File (php.ini) Path /usr/local/etc/php
Loaded Configuration File /usr/local/etc/php/php.ini
Scan this dir for additional .ini files /usr/local/etc/php/conf.d
Additional .ini files parsed /usr/local/etc/php/conf.d/98-ddtrace.ini, /usr/local/etc/php/conf.d/docker-php-ext-awscrt.ini, /usr/local/etc/php/conf.d/docker-php-ext-bcmath.ini, /usr/local/etc/php/conf.d/docker-php-ext-pcntl.ini, /usr/local/etc/php/conf.d/docker-php-ext-pdo_pgsql.ini, /usr/local/etc/php/conf.d/docker-php-ext-redis.ini, /usr/local/etc/php/conf.d/docker-php-ext-sockets.ini, /usr/local/etc/php/conf.d/docker-php-ext-sodium.ini, /usr/local/etc/php/conf.d/docker-php-ext-zip.ini
PHP API 20250925
PHP Extension 20250925
Zend Extension 420250925
Zend Extension Build API420250925,TS
PHP Extension Build API20250925,TS
PHP Integer Size 64 bits
Debug Build no
Thread Safety enabled
Thread API POSIX Threads
Zend Signal Handling disabled
Zend Memory Manager disabled
Zend Multibyte Support provided by mbstring
Zend Max Execution Timers enabled
IPv6 Support enabled
DTrace Support disabled
Registered PHP Streams https, ftps, compress.zlib, php, file, glob, data, http, ftp, phar, zip
Registered Stream Socket Transports tcp, udp, unix, udg, ssl, tls, tlsv1.0, tlsv1.1, tlsv1.2, tlsv1.3
Registered Stream Filters zlib.*, convert.iconv.*, string.rot13, string.toupper, string.tolower, convert.*, consumed, dechunk
Configuration
awscrt
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bcmath
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bcmath.scale 0 0
Core
PHP Version 8.5.2
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allow_url_fopen On On
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arg_separator.input & &
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extension_dir /usr/local/lib/php/extensions/no-debug-zts-20250925 /usr/local/lib/php/extensions/no-debug-zts-20250925
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file_uploads On On
hard_timeout 2 2
highlight.comment #FF8000 #FF8000
highlight.default #0000BB #0000BB
highlight.html #000000 #000000
highlight.keyword #007700 #007700
highlight.string #DD0000 #DD0000
html_errors On On
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include_path .:/usr/local/lib/php .:/usr/local/lib/php
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SMTP localhost localhost
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ctype
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curl
cURL support enabled
cURL Information 8.14.1
Age 11
Features
AsynchDNS Yes
CharConv No
Debug No
GSS-Negotiate No
IDN Yes
IPv6 Yes
krb4 No
Largefile Yes
libz Yes
NTLM Yes
NTLMWB No
SPNEGO Yes
SSL Yes
SSPI No
TLS-SRP Yes
HTTP2 Yes
GSSAPI Yes
KERBEROS5 Yes
UNIX_SOCKETS Yes
PSL Yes
HTTPS_PROXY Yes
MULTI_SSL No
BROTLI Yes
ALTSVC Yes
HTTP3 Yes
UNICODE No
ZSTD Yes
HSTS Yes
GSASL No
Protocols dict, file, ftp, ftps, gopher, gophers, http, https, imap, imaps, ldap, ldaps, mqtt, pop3, pop3s, rtmp, rtmpe, rtmps, rtmpt, rtmpte, rtmpts, rtsp, scp, sftp, smb, smbs, smtp, smtps, telnet, tftp, ws, wss
Host x86_64-pc-linux-gnu
SSL Version OpenSSL/3.5.4
ZLib Version 1.3.1
libSSH Version libssh2/1.11.1
Directive Local Value Master Value
curl.cainfo no value no value
datadog-profiling
Version 1.16.0
Profiling Enabled true
Profiling Experimental Features Enabled false
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Timeline Enabled true
Exception Profiling Enabled true
I/O Profiling Enabled false
Endpoint Collection Enabled true
Platform's CPU Time API Works true
Profiling Log Level off
Profiling Agent Endpoint unix:///var/run/datadog/apm.socket
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datadog.profiling.allocation_enabled On On
datadog.profiling.allocation_sampling_distance 4194304 4194304
datadog.profiling.enabled On On
datadog.profiling.endpoint_collection_enabled On On
datadog.profiling.exception_enabled On On
datadog.profiling.exception_message_enabled Off Off
datadog.profiling.exception_sampling_distance 100 100
datadog.profiling.experimental_allocation_enabled On On
datadog.profiling.experimental_cpu_enabled On On
datadog.profiling.experimental_cpu_time_enabled On On
datadog.profiling.experimental_exception_enabled On On
datadog.profiling.experimental_exception_sampling_distance 100 100
datadog.profiling.experimental_features_enabled Off Off
datadog.profiling.experimental_io_enabled Off Off
datadog.profiling.experimental_timeline_enabled On On
datadog.profiling.log_level off off
datadog.profiling.output_pprof no value no value
datadog.profiling.timeline_enabled On On
datadog.profiling.walltime_enabled On On
Zend OPcache
Opcode Caching Up and Running
Optimization Enabled
SHM Cache Enabled
File Cache Disabled
JIT Disabled
Startup OK
Shared memory model mmap
Cache hits 1888559
Cache misses 761
Used memory -232594744
Free memory 232594744
Wasted memory 0
Interned Strings Used memory 8434496
Interned Strings Free memory 8342720
Cached scripts 756
Cached keys 1448
Max keys 32531
OOM restarts 0
Hash keys restarts 0
Manual restarts 0
Start time 2026-03-13T14:19:23+0000
Last restart time none
Last force restart time none
Directive Local Value Master Value
opcache.blacklist_filename no value no value
opcache.dups_fix Off Off
opcache.enable On On
opcache.enable_cli On On
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opcache.error_log no value no value
opcache.file_cache no value no value
opcache.file_cache_consistency_checks On On
opcache.file_cache_only Off Off
opcache.file_cache_read_only Off Off
opcache.file_update_protection 0 0
opcache.force_restart_timeout 180 180
opcache.huge_code_pages Off Off
opcache.interned_strings_buffer 16 16
opcache.jit disable disable
opcache.jit_bisect_limit 0 0
opcache.jit_blacklist_root_trace 16 16
opcache.jit_blacklist_side_trace 8 8
opcache.jit_buffer_size 128M 128M
opcache.jit_debug 0 0
opcache.jit_hot_func 127 127
opcache.jit_hot_loop 61 61
opcache.jit_hot_return 8 8
opcache.jit_hot_side_exit 8 8
opcache.jit_max_exit_counters 8192 8192
opcache.jit_max_loop_unrolls 8 8
opcache.jit_max_polymorphic_calls 2 2
opcache.jit_max_recursive_calls 2 2
opcache.jit_max_recursive_returns 2 2
opcache.jit_max_root_traces 2048 2048
opcache.jit_max_side_traces 256 256
opcache.jit_max_trace_length 1024 1024
opcache.jit_prof_threshold 0.001 0.001
opcache.lockfile_path /tmp /tmp
opcache.log_verbosity_level 1 1
opcache.max_accelerated_files 32531 32531
opcache.max_file_size 0 0
opcache.max_wasted_percentage 5 5
opcache.memory_consumption 256M 256M
opcache.opt_debug_level 0 0
opcache.optimization_level 0x7FFEBFFF 0x7FFEBFFF
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