Bug #73005 [NEW]: In child process overdo call sem_release resulting max_acquire overflow

From: consatan at gmail dot com Operating system: Unix like OS PHP version: Irrelevant Package: Semaphore related Bug Type: Bug Bug description:In child process overdo call sem_release resulting max_acquire overflow Description: ------------ Test in OS: Debian 8.5 and CentOS 7.2.1511 PHP: 5.6.25 and 7.0.10 configure: --enable-pcntl --enable-sysvshm --enable-sysvsem --enable-sysvmsg Look like the semaphore resource in each child process is an clone not a reference. The semaphore resources state in child process was cloned from the last state before parent process triggered pcntl_fork(). Test script: --------------- <?php $ipcs = "ipcs -s -i ipcs -s | grep 0x0001e240 | awk '{print $2}' | awk 'NR==9'"; $sem = sem_get(123456, 3, 0666, 0); echo exec($ipcs) . " first\n"; for ($i = 0; $i < 3; $i++) { sem_acquire($sem); if (pcntl_fork() === 0) { echo exec($ipcs) . " $i start\n"; for ($j = 0; $j < 3; $j++) sem_release($sem); echo exec($ipcs) . " $i end\n"; exit(0); } } usleep(50000); echo exec($ipcs) . " last\n"; sem_remove($sem); Expected result: ---------------- 6 times Warning semaphore's max_acquirce <= 3 Actual result: -------------- 0 3 0 0 7128 first 0 0 0 0 7128 2 start 0 3 0 0 7138 1 start Warning: sem_release(): SysV semaphore 4 (key 0x1e240) is not currently acquired in /tmp/sem.php on line 10 0 5 0 0 7137 0 start Warning: sem_release(): SysV semaphore 4 (key 0x1e240) is not currently acquired in /tmp/sem.php on line 10 Warning: sem_release(): SysV semaphore 4 (key 0x1e240) is not currently acquired in /tmp/sem.php on line 10 0 6 0 0 7136 1 end 0 4 0 0 7137 2 end 0 1 0 0 7138 0 end 0 0 0 0 7136 last -- Edit bug report at https://bugs.php.net/bug.php?id=73005&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=73005&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=73005&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=73005&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=73005&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=73005&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=73005&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=73005&r=needscript Try newer version: https://bugs.php.net/fix.php?id=73005&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=73005&r=support Expected behavior: https://bugs.php.net/fix.php?id=73005&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=73005&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=73005&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=73005&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=73005&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=73005&r=dst IIS Stability: https://bugs.php.net/fix.php?id=73005&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=73005&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=73005&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=73005&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=73005&r=mysqlcfg