Bug #66623 [Asn->Csd]: no EINTR check on flock(LOCK_EX)

Edit report at https://bugs.php.net/bug.php?id=66623&edit=1 ID: 66623 Updated by: yohgaki@php.net Reported by: php at bof dot de Summary: no EINTR check on flock(LOCK_EX) -Status: Assigned +Status: Closed Type: Bug Package: Session related PHP Version: 5.6.0alpha1 Assigned To: yohgaki Block user comment: N Private report: N New Comment: Automatic comment on behalf of yohgaki Revision: http://git.php.net/?p=php-src.git;a=commit;h=b41a6c6f055e87d87b42bfd87fbad14a23134e4e Log: Fixed Bug #66623 no EINTR check on flock(LOCK_EX) Previous Comments: ------------------------------------------------------------------------ [2014-12-10 22:49:04] yohgaki@php.net I'll process my list of todos before PHP7, hopefully. ------------------------------------------------------------------------ [2014-10-17 13:59:18] tyrael@php.net any update on this? ------------------------------------------------------------------------ [2014-02-01 22:28:12] yohgaki@php.net Thank you for reporting. ------------------------------------------------------------------------ [2014-02-01 08:48:21] php at bof dot de Description: ------------ Noticed a problem in ext/session/mod_files.c : > Some syscalls can fail with EINTR, when a signal hits while within the > kernel. This is especially true for flock(LOCK_EX) because in the > already-locked case the second call will go to sleep for a while waiting > for the lock to clear. But it is also possible, I think, for the > pread/read/write calls. The usual handling for the case (-1 return && > errno > == EINTR) is to just repeat the call in a while loop. I think that at > least > doing so for the LOCK_EX calls, would be prudent. Re-Read the manpage (*) a bit... read/pread/write should be safe here, going to disk, and not a pipe or socket. But flock() will return EINTR when signalled and the signal handler did not use SA_RESTART. Most PHP execution will _probably_ okay anyway as $restart_syscalls is default true for pcntl_signal(), but handling would be safer anyway. ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=66623&edit=1