linux: Add fallback for 64-bit time_t SO_{RCV,SND}TIMEO

The constant values will be changed for __TIMESIZE=64, so binaries built
with 64-bit time support might fail to work properly on old kernels.
Both {get,set}sockopt will retry the syscall with the old constant
values and the timeout value adjusted when kernel returns ENOTPROTOPT.

It also adds an internal only SO_{RCV,SND}TIMEO where
COMPAT_SO_{RCV,SND}TIMEO_OLD indicates pre 32-bit time support and
COMPAT_SO_{RCV,SND}TIMEO_NEW indicates time64 support.  It allows to
refer to constant independently of the time_t ABI and kernel version
used.

Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15
kernel).

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>

7 files changed, 276 insertions, 15 deletions

diff --git a/sysdeps/unix/sysv/linux/getsockopt.c b/sysdeps/unix/sysv/linux/getsockopt.c
index 76ee8a9..688a7de 100644
--- a/sysdeps/unix/sysv/linux/getsockopt.c
+++ b/sysdeps/unix/sysv/linux/getsockopt.c
@@ -15,16 +15,15 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#include <errno.h>
-#include <signal.h>
 #include <sys/socket.h>
-
+#include <time.h>
+#include <sysdep.h>
 #include <socketcall.h>
-#include <kernel-features.h>
-#include <sys/syscall.h>
+#include <socket-constants-time64.h>
 
-int
-__getsockopt (int fd, int level, int optname, void *optval, socklen_t *len)
+static int
+getsockopt_syscall (int fd, int level, int optname, void *optval,
+		    socklen_t *len)
 {
 #ifdef __ASSUME_GETSOCKOPT_SYSCALL
   return INLINE_SYSCALL (getsockopt, 5, fd, level, optname, optval, len);
@@ -32,4 +31,61 @@ __getsockopt (int fd, int level, int optname, void *optval, socklen_t *len)
   return SOCKETCALL (getsockopt, fd, level, optname, optval, len);
 #endif
 }
+
+#ifndef __ASSUME_TIME64_SYSCALLS
+static int
+getsockopt32 (int fd, int level, int optname, void *optval,
+	      socklen_t *len)
+{
+  int r = -1;
+
+  if (level != SOL_SOCKET)
+    return r;
+
+  switch (optname)
+    {
+    case COMPAT_SO_RCVTIMEO_NEW:
+    case COMPAT_SO_SNDTIMEO_NEW:
+      {
+	if (optname == COMPAT_SO_RCVTIMEO_NEW)
+	  optname = COMPAT_SO_RCVTIMEO_OLD;
+	if (optname == COMPAT_SO_SNDTIMEO_NEW)
+	  optname = COMPAT_SO_SNDTIMEO_OLD;
+
+	struct __timeval32 tv32;
+	r = getsockopt_syscall (fd, level, optname, &tv32,
+				(socklen_t[]) { sizeof tv32 });
+	if (r < 0)
+	  break;
+
+	/* POSIX states that if the size of the option value is greater than
+	   then option length, the option value argument shall be silently
+	   truncated.  */
+	if (*len >= sizeof (struct __timeval64))
+	  {
+	    struct __timeval64 *tv64 = (struct __timeval64 *) optval;
+	    *tv64 = valid_timeval32_to_timeval64 (tv32);
+	    *len = sizeof (*tv64);
+	  }
+	else
+	  memcpy (optval, &tv32, sizeof tv32);
+      }
+    }
+
+  return r;
+}
+#endif
+
+int
+__getsockopt (int fd, int level, int optname, void *optval, socklen_t *len)
+{
+  int r = getsockopt_syscall (fd, level, optname, optval, len);
+
+#ifndef __ASSUME_TIME64_SYSCALLS
+  if (r == -1 && errno == ENOPROTOOPT)
+    r = getsockopt32 (fd, level, optname, optval, len);
+#endif
+
+ return r;
+}
 weak_alias (__getsockopt, getsockopt)
diff --git a/sysdeps/unix/sysv/linux/hppa/socket-constants-time64.h b/sysdeps/unix/sysv/linux/hppa/socket-constants-time64.h
new file mode 100644
index 0000000..9fe7576
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/hppa/socket-constants-time64.h
@@ -0,0 +1,30 @@
+/* Compat socket constants used in 64-bit compat code.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _SOCKET_CONSTANTS_TIME64_H
+#define _SOCKET_CONSTANTS_TIME64_H
+
+/* The compat code requires the SO_* constants used for both 32 and 64-bit
+   time_t, however they were only added on v5.1 kernel.  */
+
+#define COMPAT_SO_RCVTIMEO_OLD 4102
+#define COMPAT_SO_SNDTIMEO_OLD 4101
+#define COMPAT_SO_RCVTIMEO_NEW 16448
+#define COMPAT_SO_SNDTIMEO_NEW 16449
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/mips/socket-constants-time64.h b/sysdeps/unix/sysv/linux/mips/socket-constants-time64.h
new file mode 100644
index 0000000..1252a8a
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/mips/socket-constants-time64.h
@@ -0,0 +1,30 @@
+/* Compat socket constants used in 64-bit compat code.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _SOCKET_CONSTANTS_TIME64_H
+#define _SOCKET_CONSTANTS_TIME64_H
+
+/* The compat code requires the SO_* constants used for both 32 and 64-bit
+   time_t, however they were only added on v5.1 kernel.  */
+
+#define COMPAT_SO_RCVTIMEO_OLD 4102
+#define COMPAT_SO_SNDTIMEO_OLD 4101
+#define COMPAT_SO_RCVTIMEO_NEW 66
+#define COMPAT_SO_SNDTIMEO_NEW 67
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/powerpc/socket-constants-time64.h b/sysdeps/unix/sysv/linux/powerpc/socket-constants-time64.h
new file mode 100644
index 0000000..26e8b71
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/powerpc/socket-constants-time64.h
@@ -0,0 +1,30 @@
+/* Compat socket constants used in 64-bit compat code.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _SOCKET_CONSTANTS_TIME64_H
+#define _SOCKET_CONSTANTS_TIME64_H
+
+/* The compat code requires the SO_* constants used for both 32 and 64-bit
+   time_t, however they were only added on v5.1 kernel.  */
+
+#define COMPAT_SO_RCVTIMEO_OLD 18
+#define COMPAT_SO_SNDTIMEO_OLD 19
+#define COMPAT_SO_RCVTIMEO_NEW 66
+#define COMPAT_SO_SNDTIMEO_NEW 67
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/setsockopt.c b/sysdeps/unix/sysv/linux/setsockopt.c
index 12fd7bd..6505202 100644
--- a/sysdeps/unix/sysv/linux/setsockopt.c
+++ b/sysdeps/unix/sysv/linux/setsockopt.c
@@ -15,21 +15,76 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#include <errno.h>
-#include <signal.h>
 #include <sys/socket.h>
-
+#include <time.h>
+#include <sysdep.h>
 #include <socketcall.h>
-#include <kernel-features.h>
-#include <sys/syscall.h>
+#include <socket-constants-time64.h>
 
-int
-setsockopt (int fd, int level, int optname, const void *optval, socklen_t len)
+static int
+setsockopt_syscall (int fd, int level, int optname, const void *optval,
+		    socklen_t len)
 {
 #ifdef __ASSUME_SETSOCKOPT_SYSCALL
-  return INLINE_SYSCALL (setsockopt, 5, fd, level, optname, optval, len);
+  return INLINE_SYSCALL_CALL (setsockopt, fd, level, optname, optval, len);
 #else
   return SOCKETCALL (setsockopt, fd, level, optname, optval, len);
 #endif
 }
+
+#ifndef __ASSUME_TIME64_SYSCALLS
+static int
+setsockopt32 (int fd, int level, int optname, const void *optval,
+	      socklen_t len)
+{
+  int r = -1;
+
+  if (level != SOL_SOCKET)
+    return r;
+
+  switch (optname)
+    {
+    case COMPAT_SO_RCVTIMEO_NEW:
+    case COMPAT_SO_SNDTIMEO_NEW:
+      {
+        if (len < sizeof (struct __timeval64))
+	  {
+	    __set_errno (EINVAL);
+	    break;
+	  }
+
+	struct __timeval64 *tv64 = (struct __timeval64 *) optval;
+	if (! in_time_t_range (tv64->tv_sec))
+	  {
+	    __set_errno (EOVERFLOW);
+	    break;
+	  }
+
+	if (optname == COMPAT_SO_RCVTIMEO_NEW)
+	  optname = COMPAT_SO_RCVTIMEO_OLD;
+	if (optname == COMPAT_SO_SNDTIMEO_NEW)
+	  optname = COMPAT_SO_SNDTIMEO_OLD;
+
+	struct __timeval32 tv32 = valid_timeval64_to_timeval32 (*tv64);
+
+	r = setsockopt_syscall (fd, level, optname, &tv32, sizeof (tv32));
+      }
+    }
+
+  return r;
+}
+#endif
+
+int
+setsockopt (int fd, int level, int optname, const void *optval, socklen_t len)
+{
+  int r = setsockopt_syscall (fd, level, optname, optval, len);
+
+#ifndef __ASSUME_TIME64_SYSCALLS
+  if (r == -1 && errno == ENOPROTOOPT)
+    r = setsockopt32 (fd, level, optname, optval, len);
+#endif
+
+  return r;
+}
 weak_alias (setsockopt, __setsockopt)
diff --git a/sysdeps/unix/sysv/linux/socket-constants-time64.h b/sysdeps/unix/sysv/linux/socket-constants-time64.h
new file mode 100644
index 0000000..d09c39d
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/socket-constants-time64.h
@@ -0,0 +1,30 @@
+/* Compat socket constants used in 64-bit compat code.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _SOCKET_CONSTANTS_TIME64_H
+#define _SOCKET_CONSTANTS_TIME64_H
+
+/* The compat code requires the SO_* constants used for both 32 and 64-bit
+   time_t, however they were only added on v5.1 kernel.  */
+
+#define COMPAT_SO_RCVTIMEO_OLD 20
+#define COMPAT_SO_SNDTIMEO_OLD 21
+#define COMPAT_SO_RCVTIMEO_NEW 66
+#define COMPAT_SO_SNDTIMEO_NEW 67
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/sparc/socket-constants-time64.h b/sysdeps/unix/sysv/linux/sparc/socket-constants-time64.h
new file mode 100644
index 0000000..f4668db
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/sparc/socket-constants-time64.h
@@ -0,0 +1,30 @@
+/* Compat socket constants used in 64-bit compat code.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _SOCKET_CONSTANTS_TIME64_H
+#define _SOCKET_CONSTANTS_TIME64_H
+
+/* The compat code requires the SO_* constants used for both 32 and 64-bit
+   time_t, however they were only added on v5.1 kernel.  */
+
+#define COMPAT_SO_RCVTIMEO_OLD 8192
+#define COMPAT_SO_SNDTIMEO_OLD 16384
+#define COMPAT_SO_RCVTIMEO_NEW 68
+#define COMPAT_SO_SNDTIMEO_NEW 69
+
+#endif