From ccd566af20dc47a5708e2e707c9624796ea79bef Mon Sep 17 00:00:00 2001 From: Daniel Black Date: Thu, 19 Apr 2018 07:38:57 +1000 Subject: [PATCH] MDEV-8743: mysqld port/socket - FD_CLOEXEC if no SOCK_CLOEXEC In MDEV-8743, the port/socket of mysqld was changed to set FD_CLOEXEC. The existing mysql_socket_socket function already set that with SOCK_CLOEXEC when the socket was created. So here we move the fcntl functionality to the mysql_socket_socket as port/socket are the only callers. Preprocessor checks of SOCK_CLOEXEC cannot be done as its a 0 if not there and SOCK_CLOEXEC (being the value of the enum in bits/socket_type.h) Preprocesssor logic for arithmetic and non-arithmetic defines are hard/nonportable/ugly to read. As such we just check in my_global.h and define HAVE_SOCK_CLOEXEC if we have it. There was a disparity in behaviour between defined(WITH_WSREP) and not depending on the OS, so the WITH_WSREP condition was removed from setting calling fcntl. All sockets are now maked SOCK_CLOEXEC/FD_CLOEXEC. strace of mysqld with SOCK_CLOEXEC: socket(AF_INET, SOCK_STREAM|SOCK_CLOEXEC, IPPROTO_TCP) = 10 write(2, "180419 14:52:40 [Note] Server socket created on IP: '127.0.0.1'.\n", 65180419 14:52:40 [Note] Server socket created on IP: '127.0.0.1'. ) = 65 setsockopt(10, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 bind(10, {sa_family=AF_INET, sin_port=htons(16020), sin_addr=inet_addr("127.0.0.1")}, 16) = 0 listen(10, 150) = 0 socket(AF_INET, SOCK_STREAM|SOCK_CLOEXEC, IPPROTO_TCP) = 11 write(2, "180419 14:52:40 [Note] Server socket created on IP: '127.0.0.1'.\n", 65180419 14:52:40 [Note] Server socket created on IP: '127.0.0.1'. ) = 65 setsockopt(11, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 bind(11, {sa_family=AF_INET, sin_port=htons(16021), sin_addr=inet_addr("127.0.0.1")}, 16) = 0 listen(11, 150) = 0 socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0) = 12 unlink("/home/dan/repos/build-mariadb-server-10.0/mysql-test/var/tmp/mysqld.1.sock") = -1 ENOENT (No such file or directory) setsockopt(12, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 umask(000) = 006 bind(12, {sa_family=AF_UNIX, sun_path="/home/dan/repos/build-mariadb-server-10.0/mysql-test/var/tmp/mysqld.1.sock"}, 110) = 0 umask(006) = 000 listen(12, 150) = 0 --- include/my_global.h | 2 ++ include/mysql/psi/mysql_socket.h | 6 ++++++ sql/mysqld.cc | 7 ------- 3 files changed, 8 insertions(+), 7 deletions(-) diff --git a/include/my_global.h b/include/my_global.h index ad1527d7b37..057c613d64c 100644 --- a/include/my_global.h +++ b/include/my_global.h @@ -608,6 +608,8 @@ typedef SOCKET_SIZE_TYPE size_socket; #endif #ifndef SOCK_CLOEXEC #define SOCK_CLOEXEC 0 +#else +#define HAVE_SOCK_CLOEXEC #endif /* additional file share flags for win32 */ diff --git a/include/mysql/psi/mysql_socket.h b/include/mysql/psi/mysql_socket.h index bd05ef9b8a9..70700a733d8 100644 --- a/include/mysql/psi/mysql_socket.h +++ b/include/mysql/psi/mysql_socket.h @@ -562,6 +562,12 @@ inline_mysql_socket_socket (key, (const my_socket*)&mysql_socket.fd, NULL, 0); } #endif + + /* SOCK_CLOEXEC isn't always a number - can't preprocessor compare */ +#if defined(HAVE_FCNTL) && defined(FD_CLOEXEC) && !defined(HAVE_SOCK_CLOEXEC) + (void) fcntl(mysql_socket.fd, F_SETFD, FD_CLOEXEC); +#endif + return mysql_socket; } diff --git a/sql/mysqld.cc b/sql/mysqld.cc index 8575709203c..15f4af5edbb 100644 --- a/sql/mysqld.cc +++ b/sql/mysqld.cc @@ -2593,10 +2593,6 @@ static MYSQL_SOCKET activate_tcp_port(uint port) socket_errno); unireg_abort(1); } -#if defined(WITH_WSREP) && defined(HAVE_FCNTL) && defined(FD_CLOEXEC) - (void) fcntl(mysql_socket_getfd(ip_sock), F_SETFD, FD_CLOEXEC); -#endif /* WITH_WSREP */ - DBUG_RETURN(ip_sock); } @@ -2714,9 +2710,6 @@ static void network_init(void) if (mysql_socket_listen(unix_sock,(int) back_log) < 0) sql_print_warning("listen() on Unix socket failed with error %d", socket_errno); -#if defined(WITH_WSREP) && defined(HAVE_FCNTL) - (void) fcntl(mysql_socket_getfd(unix_sock), F_SETFD, FD_CLOEXEC); -#endif /* WITH_WSREP */ } #endif DBUG_PRINT("info",("server started"));