[PATCH 1/2] support: Add support_socket_time64_timestamp

[PATCH 1/2] support: Add support_socket_time64_timestamp

[Adhemerval Zanella]

Check if the socket support 64-bit network packages timestamps
(SO_TIMESTAMP and SO_TIMESTAMPNS).  This will be used on recvmsg
and recvmmsg tests to check if the timestamp should be generated.
---
 support/Makefile                          |  1 +
 support/support.h                         |  3 ++
 support/support_socket_time64_timestamp.c | 64 +++++++++++++++++++++++
 3 files changed, 68 insertions(+)
 create mode 100644 support/support_socket_time64_timestamp.c

diff --git a/support/Makefile b/support/Makefile
index 2a0731796f..c34ef2a08b 100644
--- a/support/Makefile
+++ b/support/Makefile
@@ -78,6 +78,7 @@ libsupport-routines = \
   support_set_small_thread_stack_size \
   support_shared_allocate \
   support_small_stack_thread_attribute \
+  support_socket_time64_timestamp \
   support_stat_nanoseconds \
   support_subprocess \
   support_test_compare_blob \
diff --git a/support/support.h b/support/support.h
index 837a806531..ba79271d6d 100644
--- a/support/support.h
+++ b/support/support.h
@@ -176,6 +176,9 @@ extern bool support_select_modifies_timeout (void);
    tv_usec larger than 1000000.  */
 extern bool support_select_normalizes_timeout (void);
 
+/* Return true if socket FD supports 64-bit timestamps.  */
+extern bool support_socket_time64_timestamp (int fd);
+
 /* Create a timer that trigger after SEC seconds and NSEC nanoseconds.  If
    REPEAT is true the timer will repeat indefinitely.  If CALLBACK is not
    NULL, the function will be called when the timer expires; otherwise a
diff --git a/support/support_socket_time64_timestamp.c b/support/support_socket_time64_timestamp.c
new file mode 100644
index 0000000000..a2b059a13d
--- /dev/null
+++ b/support/support_socket_time64_timestamp.c
@@ -0,0 +1,64 @@
+/* Return whether socket supports 64-bit timestamps.
+   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/>.  */
+
+#include <errno.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <sys/socket.h>
+#include <support/support.h>
+
+#ifdef __linux__
+# include <socket-constants-time64.h>
+
+static int
+__attribute_used__
+getsockopt_syscall (int fd)
+{
+  int level = SOL_SOCKET;
+  int optname = COMPAT_SO_TIMESTAMP_NEW;
+  int optval;
+  socklen_t len = sizeof (optval);
+
+  int r = syscall (__NR_getsockopt, fd, level, optname, &optval, &len);
+#  ifdef __NR_socketcall
+  if (r == -1 && errno == ENOSYS)
+    {
+      long int args[] = { fd, level, optname, (long int) &optval,
+			  sizeof (optval) };
+      r = syscall (__NR_socketcall, 15 /* SOCKOP_getsockopt  */ , args);
+    }
+#  endif
+  return r;
+}
+#endif
+
+bool
+support_socket_time64_timestamp (int fd)
+{
+#ifdef __linux__
+# if __LINUX_KERNEL_VERSION >= 0x050100                          \
+   || __WORDSIZE == 64                                           \
+   || (defined __SYSCALL_WORDSIZE && __SYSCALL_WORDSIZE == 64)
+  return true;
+# else
+  return getsockopt_syscall (fd) != -1;
+# endif
+#else
+  return false;
+#endif
+}
-- 
2.30.2

[PATCH 2/2] linux: Fix ancillary 64-bit time timestamp conversion (BZ #28349, BZ #28350)

[Adhemerval Zanella]

The __convert_scm_timestamps() only updates the control message last
pointer for SOL_SOCKET type, so if the message control buffer contains
multiple ancillary message types the converted timestamp one might
overwrite a valid message.

The test check if the extra ancillary space is correctly handled
by recvmsg/recvmmsg, where if there is no extra space for the 64-bit
time_t converted message the control buffer should be marked with
MSG_TRUNC.  It also check if recvmsg/recvmmsg handle correctly multiple
ancillary data.

Checked on x86_64-linux and on i686-linux-gnu on both 5.11 and
4.15 kernel.
---
 sysdeps/unix/sysv/linux/Makefile              |   3 +
 .../unix/sysv/linux/convert_scm_timestamps.c  |  40 +--
 .../sysv/linux/tst-socket-timestamp-time64.c  |   1 +
 .../unix/sysv/linux/tst-socket-timestamp.c    | 338 ++++++++++++++++++
 4 files changed, 362 insertions(+), 20 deletions(-)
 create mode 100644 sysdeps/unix/sysv/linux/tst-socket-timestamp-time64.c
 create mode 100644 sysdeps/unix/sysv/linux/tst-socket-timestamp.c

diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index 76ad06361c..3399c87468 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -262,6 +262,9 @@ sysdep_routines += cmsg_nxthdr
 CFLAGS-recvmmsg.c = -fexceptions -fasynchronous-unwind-tables
 CFLAGS-sendmmsg.c = -fexceptions -fasynchronous-unwind-tables
 
+tests += tst-socket-timestamp
+tests-time64 += tst-socket-timestamp-time64
+
 tests-special += $(objpfx)tst-socket-consts.out
 $(objpfx)tst-socket-consts.out: ../sysdeps/unix/sysv/linux/tst-socket-consts.py
 	PYTHONPATH=../scripts \
diff --git a/sysdeps/unix/sysv/linux/convert_scm_timestamps.c b/sysdeps/unix/sysv/linux/convert_scm_timestamps.c
index 00c934c413..5ee930035b 100644
--- a/sysdeps/unix/sysv/linux/convert_scm_timestamps.c
+++ b/sysdeps/unix/sysv/linux/convert_scm_timestamps.c
@@ -54,26 +54,26 @@ __convert_scm_timestamps (struct msghdr *msg, socklen_t msgsize)
        cmsg != NULL;
        cmsg = CMSG_NXTHDR (msg, cmsg))
     {
-      if (cmsg->cmsg_level != SOL_SOCKET)
-	continue;
-
-      switch (cmsg->cmsg_type)
+      if (cmsg->cmsg_level == SOL_SOCKET)
 	{
-	case COMPAT_SO_TIMESTAMP_OLD:
-	  if (type != 0)
-	    break;
-	  type = COMPAT_SO_TIMESTAMP_NEW;
-	  goto common;
-
-	case COMPAT_SO_TIMESTAMPNS_OLD:
-	  type = COMPAT_SO_TIMESTAMPNS_NEW;
-
-	/* fallthrough  */
-	common:
-	  memcpy (tmp, CMSG_DATA (cmsg), sizeof (tmp));
-	  tvts[0] = tmp[0];
-	  tvts[1] = tmp[1];
-	  break;
+	  switch (cmsg->cmsg_type)
+	    {
+	    case COMPAT_SO_TIMESTAMP_OLD:
+	      if (type != 0)
+		break;
+	      type = COMPAT_SO_TIMESTAMP_NEW;
+	      goto common;
+
+	    case COMPAT_SO_TIMESTAMPNS_OLD:
+	      type = COMPAT_SO_TIMESTAMPNS_NEW;
+
+	    /* fallthrough  */
+	    common:
+	      memcpy (tmp, CMSG_DATA (cmsg), sizeof (tmp));
+	      tvts[0] = tmp[0];
+	      tvts[1] = tmp[1];
+	      break;
+	    }
 	}
 
       last = cmsg;
@@ -89,7 +89,7 @@ __convert_scm_timestamps (struct msghdr *msg, socklen_t msgsize)
     }
 
   msg->msg_controllen += CMSG_SPACE (sizeof tvts);
-  cmsg = CMSG_NXTHDR(msg, last);
+  cmsg = CMSG_NXTHDR (msg, last);
   if (cmsg == NULL)
     return;
   cmsg->cmsg_level = SOL_SOCKET;
diff --git a/sysdeps/unix/sysv/linux/tst-socket-timestamp-time64.c b/sysdeps/unix/sysv/linux/tst-socket-timestamp-time64.c
new file mode 100644
index 0000000000..ae424c2a70
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tst-socket-timestamp-time64.c
@@ -0,0 +1 @@
+#include "tst-socket-timestamp.c"
diff --git a/sysdeps/unix/sysv/linux/tst-socket-timestamp.c b/sysdeps/unix/sysv/linux/tst-socket-timestamp.c
new file mode 100644
index 0000000000..152325a43c
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tst-socket-timestamp.c
@@ -0,0 +1,338 @@
+/* Check recvmsg/recvmmsg 64-bit timestamp support.
+   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/>.  */
+
+#include <array_length.h>
+#include <arpa/inet.h>
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+#include <support/check.h>
+#include <support/next_to_fault.h>
+#include <support/support.h>
+#include <support/test-driver.h>
+#include <support/xunistd.h>
+#include <support/xsocket.h>
+#include <sys/mman.h>
+
+/* Some extra space added for ancillary data, it might be used to convert
+   32-bit timestamp to 64-bit for _TIME_BITS=64.  */
+enum { slack_max_size = 64 };
+static const int slack[] = { 0, 4, 8, 16, 32, slack_max_size };
+
+static bool support_64_timestamp;
+/* AF_INET socket and address used to send and receive data.  */
+static int srv;
+static struct sockaddr_in srv_addr;
+
+static int
+do_sendto (const struct sockaddr_in *addr, int nmsgs)
+{
+  int s = xsocket (AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
+  xconnect (s, (const struct sockaddr *) addr, sizeof (*addr));
+
+  for (int i = 0; i < nmsgs; i++)
+    xsendto (s, &i, sizeof (i), 0, (const struct sockaddr *) addr,
+	     sizeof (*addr));
+
+  return 0;
+}
+
+static void
+do_recvmsg_slack_ancillary (bool use_multi_call, int s, void *cmsg,
+			    size_t slack, size_t tsize, int exp_msg)
+{
+  int msg;
+  struct iovec iov =
+    {
+      .iov_base = &msg,
+      .iov_len = sizeof (msg)
+    };
+  size_t msgs = CMSG_SPACE (tsize) + slack;
+  struct mmsghdr mmhdr =
+    {
+      .msg_hdr =
+      {
+        .msg_name = NULL,
+        .msg_namelen = 0,
+        .msg_iov = &iov,
+        .msg_iovlen = 1,
+        .msg_controllen = msgs,
+        .msg_control = cmsg != NULL ? cmsg - msgs : NULL,
+      },
+    };
+
+  int r;
+  if (use_multi_call)
+    {
+      r = recvmmsg (s, &mmhdr, 1, 0, NULL);
+      if (r >= 0)
+	r = mmhdr.msg_len;
+    }
+  else
+    r = recvmsg (s, &mmhdr.msg_hdr, 0);
+  TEST_COMPARE (r, sizeof (int));
+  TEST_COMPARE (msg, exp_msg);
+
+  if (cmsg == NULL)
+    return;
+
+  /* A timestamp is expected if 32-bit timestamp are used (support in every
+     configuration) or if underlying kernel support 64-bit timestamps.
+     Otherwise recvmsg will need extra space do add the 64-bit timestamp.  */
+  bool exp_timestamp;
+  if (sizeof (time_t) == 4 || support_64_timestamp)
+    exp_timestamp = true;
+   else
+    exp_timestamp = slack >= CMSG_SPACE (tsize);
+
+  bool timestamp = false;
+  for (struct cmsghdr *cmsg = CMSG_FIRSTHDR (&mmhdr.msg_hdr);
+       cmsg != NULL;
+       cmsg = CMSG_NXTHDR (&mmhdr.msg_hdr, cmsg))
+    {
+      if (cmsg->cmsg_level != SOL_SOCKET)
+	continue;
+      if (cmsg->cmsg_type == SCM_TIMESTAMP
+	  && cmsg->cmsg_len == CMSG_LEN (sizeof (struct timeval)))
+	{
+	  struct timeval tv;
+	  memcpy (&tv, CMSG_DATA (cmsg), sizeof (tv));
+	  if (test_verbose)
+	    printf ("SCM_TIMESTAMP:   {%jd, %jd}\n", (intmax_t)tv.tv_sec,
+		    (intmax_t)tv.tv_usec);
+	  timestamp = true;
+	}
+      else if (cmsg->cmsg_type == SCM_TIMESTAMPNS
+	       && cmsg->cmsg_len == CMSG_LEN (sizeof (struct timespec)))
+	{
+	  struct timespec ts;
+	  memcpy (&ts, CMSG_DATA (cmsg), sizeof (ts));
+	  if (test_verbose)
+	    printf ("SCM_TIMESTAMPNS: {%jd, %jd}\n", (intmax_t)ts.tv_sec,
+		    (intmax_t)ts.tv_nsec);
+	  timestamp = true;
+	}
+    }
+
+  /* If there is not timestamp in the ancilliary data, recvmsg should set
+     the flag inidcating it.  */
+  if (exp_timestamp && !timestamp)
+    TEST_VERIFY (mmhdr.msg_hdr.msg_flags & MSG_TRUNC);
+  else
+    TEST_COMPARE (timestamp, exp_timestamp);
+}
+
+/* Check if the extra anciallry space is correctly handled by recvmsg and
+   recvmmsg: if there is no extra space for the 64-bit timestamp the syscall
+   should set MSG_TRUNC flag, otherwise an extra cmsghdr with the converted
+   timestamp is appended at the message control buffer.  */
+static void
+do_test_slack_space (void)
+{
+  /* Setup the ancillary data buffer with an extra page with PROT_NONE to
+     check the possible timestamp conversion on some systems.  */
+  struct support_next_to_fault nf =
+    support_next_to_fault_allocate (slack_max_size);
+  void *msgbuf = nf.buffer + slack_max_size;
+
+  /* Enable the timestamp using struct timeval precision.  */
+  {
+    int r = setsockopt (srv, SOL_SOCKET, SO_TIMESTAMP, &(int){1},
+			sizeof (int));
+    TEST_VERIFY_EXIT (r != -1);
+  }
+  /* Check recvmsg.  */
+  do_sendto (&srv_addr, array_length (slack));
+  for (int s = 0; s < array_length (slack); s++)
+    do_recvmsg_slack_ancillary (false, srv, msgbuf, slack[s],
+				sizeof (struct timeval), s);
+  /* Check recvmmsg.  */
+  do_sendto (&srv_addr, array_length (slack));
+  for (int s = 0; s < array_length (slack); s++)
+    do_recvmsg_slack_ancillary (true, srv, msgbuf, slack[s],
+				sizeof (struct timeval), s);
+
+  /* Now enable timestamp using a higher precision, it overwrites the previous
+     precision.  */
+  {
+    int r = setsockopt (srv, SOL_SOCKET, SO_TIMESTAMPNS, &(int){1},
+			sizeof (int));
+    TEST_VERIFY_EXIT (r != -1);
+  }
+  /* Check recvmsg.  */
+  do_sendto (&srv_addr, array_length (slack));
+  for (int s = 0; s < array_length (slack); s++)
+    do_recvmsg_slack_ancillary (false, srv, msgbuf, slack[s],
+				sizeof (struct timespec), s);
+  /* Check recvmmsg.  */
+  do_sendto (&srv_addr, array_length (slack));
+  for (int s = 0; s < array_length (slack); s++)
+    do_recvmsg_slack_ancillary (true, srv, msgbuf, slack[s],
+				sizeof (struct timespec), s);
+
+  support_next_to_fault_free (&nf);
+}
+
+/* Check if the converted 64-bit timestamp is correctly appended when there
+   are multiple ancillary messages.  */
+static void
+do_recvmsg_multiple_ancillary (bool use_multi_call, int s, void *cmsg,
+			       size_t cmsgsize, int exp_msg)
+{
+  int msg;
+  struct iovec iov =
+    {
+      .iov_base = &msg,
+      .iov_len = sizeof (msg)
+    };
+  size_t msgs = cmsgsize;
+  struct mmsghdr mmhdr =
+    {
+      .msg_hdr =
+      {
+        .msg_name = NULL,
+        .msg_namelen = 0,
+        .msg_iov = &iov,
+        .msg_iovlen = 1,
+        .msg_controllen = msgs,
+        .msg_control = cmsg,
+      },
+    };
+
+  int r;
+  if (use_multi_call)
+    {
+      r = recvmmsg (s, &mmhdr, 1, 0, NULL);
+      if (r >= 0)
+	r = mmhdr.msg_len;
+    }
+  else
+    r = recvmsg (s, &mmhdr.msg_hdr, 0);
+  TEST_COMPARE (r, sizeof (int));
+  TEST_COMPARE (msg, exp_msg);
+
+  if (cmsg == NULL)
+    return;
+
+  bool timestamp = false;
+  bool origdstaddr = false;
+  for (struct cmsghdr *cmsg = CMSG_FIRSTHDR (&mmhdr.msg_hdr);
+       cmsg != NULL;
+       cmsg = CMSG_NXTHDR (&mmhdr.msg_hdr, cmsg))
+    {
+      if (cmsg->cmsg_level == SOL_IP
+	  && cmsg->cmsg_type == IP_ORIGDSTADDR
+	  && cmsg->cmsg_len >= CMSG_LEN (sizeof (struct sockaddr_in)))
+	{
+	  struct sockaddr_in sa;
+	  memcpy (&sa, CMSG_DATA (cmsg), sizeof (sa));
+	  if (test_verbose)
+	    {
+	      char str[INET_ADDRSTRLEN];
+	      inet_ntop (AF_INET, &sa.sin_addr, str, INET_ADDRSTRLEN);
+	      printf ("IP_ORIGDSTADDR:  %s:%d\n", str, ntohs (sa.sin_port));
+	    }
+	  origdstaddr = sa.sin_addr.s_addr == srv_addr.sin_addr.s_addr
+			&& sa.sin_port == srv_addr.sin_port;
+	}
+      if (cmsg->cmsg_level == SOL_SOCKET
+	  && cmsg->cmsg_type == SCM_TIMESTAMP
+	  && cmsg->cmsg_len >= CMSG_LEN (sizeof (struct timeval)))
+	{
+	  struct timeval tv;
+	  memcpy (&tv, CMSG_DATA (cmsg), sizeof (tv));
+	  if (test_verbose)
+	    printf ("SCM_TIMESTAMP:   {%jd, %jd}\n", (intmax_t)tv.tv_sec,
+		    (intmax_t)tv.tv_usec);
+	  timestamp = true;
+	}
+    }
+
+  /* If there is not timestamp in the ancilliary data, recvmsg should set
+     the flag inidcating it.  */
+  if (!timestamp)
+    TEST_VERIFY (mmhdr.msg_hdr.msg_flags & MSG_TRUNC);
+  else
+    TEST_COMPARE (timestamp, true);
+  TEST_COMPARE (origdstaddr, true);
+}
+
+static void
+do_test_multiple_ancillary (void)
+{
+  {
+    int r = setsockopt (srv, SOL_SOCKET, SO_TIMESTAMP, &(int){1},
+			sizeof (int));
+    TEST_VERIFY_EXIT (r != -1);
+  }
+  {
+    int r = setsockopt (srv, IPPROTO_IP, IP_RECVORIGDSTADDR, &(int){1},
+			sizeof (int));
+    TEST_VERIFY_EXIT (r != -1);
+  }
+
+  /* Enougth data for default SO_TIMESTAMP, the IP_RECVORIGDSTADDR, and the
+     extra 64-bit SO_TIMESTAMP.  */
+  enum { msgbuflen = CMSG_SPACE (2 * sizeof (uint64_t))
+		     + CMSG_SPACE (sizeof (struct sockaddr_in))
+		     + CMSG_SPACE (2 * sizeof (uint64_t)) };
+  char msgbuf[msgbuflen];
+
+  enum { nmsgs = 8 };
+  /* Check recvmsg.  */
+  do_sendto (&srv_addr, nmsgs);
+  for (int s = 0; s < nmsgs; s++)
+    do_recvmsg_multiple_ancillary (false, srv, msgbuf, msgbuflen, s);
+  /* Check recvmmsg.  */
+  do_sendto (&srv_addr, nmsgs);
+  for (int s = 0; s < nmsgs; s++)
+    do_recvmsg_multiple_ancillary (true, srv, msgbuf, msgbuflen, s);
+}
+
+static int
+do_test (void)
+{
+  srv = xsocket (AF_INET, SOCK_DGRAM, 0);
+  srv_addr = (struct sockaddr_in) {
+    .sin_family = AF_INET,
+    .sin_addr = {.s_addr = htonl (INADDR_LOOPBACK) },
+  };
+  xbind (srv, (struct sockaddr *) &srv_addr, sizeof (srv_addr));
+  {
+    socklen_t sa_len = sizeof (srv_addr);
+    xgetsockname (srv, (struct sockaddr *) &srv_addr, &sa_len);
+    TEST_VERIFY (sa_len == sizeof (srv_addr));
+  }
+
+  TEST_COMPARE (recvmsg (-1, NULL, 0), -1);
+  TEST_COMPARE (errno, EBADF);
+  TEST_COMPARE (recvmmsg (-1, NULL, 0, 0, NULL), -1);
+  TEST_COMPARE (errno, EBADF);
+
+  /* If underlying kernel does not support   */
+  support_64_timestamp = support_socket_time64_timestamp (srv);
+
+  do_test_slack_space ();
+  do_test_multiple_ancillary ();
+
+  xclose (srv);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
-- 
2.30.2

Re: [PATCH 1/2] support: Add support_socket_time64_timestamp

[Michael Hudson-Doyle]

On Wed, 29 Sept 2021 at 02:40, Adhemerval Zanella via Libc-alpha <
libc-alpha@sourceware.org> wrote:

> Check if the socket support 64-bit network packages timestamps
> (SO_TIMESTAMP and SO_TIMESTAMPNS).  This will be used on recvmsg
> and recvmmsg tests to check if the timestamp should be generated.
> ---
>  support/Makefile                          |  1 +
>  support/support.h                         |  3 ++
>  support/support_socket_time64_timestamp.c | 64 +++++++++++++++++++++++
>  3 files changed, 68 insertions(+)
>  create mode 100644 support/support_socket_time64_timestamp.c
>
> diff --git a/support/Makefile b/support/Makefile
> index 2a0731796f..c34ef2a08b 100644
> --- a/support/Makefile
> +++ b/support/Makefile
> @@ -78,6 +78,7 @@ libsupport-routines = \
>    support_set_small_thread_stack_size \
>    support_shared_allocate \
>    support_small_stack_thread_attribute \
> +  support_socket_time64_timestamp \
>    support_stat_nanoseconds \
>    support_subprocess \
>    support_test_compare_blob \
> diff --git a/support/support.h b/support/support.h
> index 837a806531..ba79271d6d 100644
> --- a/support/support.h
> +++ b/support/support.h
> @@ -176,6 +176,9 @@ extern bool support_select_modifies_timeout (void);
>     tv_usec larger than 1000000.  */
>  extern bool support_select_normalizes_timeout (void);
>
> +/* Return true if socket FD supports 64-bit timestamps.  */
> +extern bool support_socket_time64_timestamp (int fd);
> +
>  /* Create a timer that trigger after SEC seconds and NSEC nanoseconds.  If
>     REPEAT is true the timer will repeat indefinitely.  If CALLBACK is not
>     NULL, the function will be called when the timer expires; otherwise a
> diff --git a/support/support_socket_time64_timestamp.c
> b/support/support_socket_time64_timestamp.c
> new file mode 100644
> index 0000000000..a2b059a13d
> --- /dev/null
> +++ b/support/support_socket_time64_timestamp.c
> @@ -0,0 +1,64 @@
> +/* Return whether socket supports 64-bit timestamps.
> +   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/>.  */
> +
> +#include <errno.h>
> +#include <unistd.h>
> +#include <sys/syscall.h>
> +#include <sys/socket.h>
> +#include <support/support.h>
> +
> +#ifdef __linux__
> +# include <socket-constants-time64.h>
> +
> +static int
> +__attribute_used__
> +getsockopt_syscall (int fd)
>

I don't find this function name explains what it does very clearly -- maybe
so_timestamp_new_supported or something like that would be better?

Cheers,
mwh


> +{
> +  int level = SOL_SOCKET;
> +  int optname = COMPAT_SO_TIMESTAMP_NEW;
> +  int optval;
> +  socklen_t len = sizeof (optval);
> +
> +  int r = syscall (__NR_getsockopt, fd, level, optname, &optval, &len);
> +#  ifdef __NR_socketcall
> +  if (r == -1 && errno == ENOSYS)
> +    {
> +      long int args[] = { fd, level, optname, (long int) &optval,
> +                         sizeof (optval) };
> +      r = syscall (__NR_socketcall, 15 /* SOCKOP_getsockopt  */ , args);
> +    }
> +#  endif
> +  return r;
> +}
> +#endif
> +
> +bool
> +support_socket_time64_timestamp (int fd)
> +{
> +#ifdef __linux__
> +# if __LINUX_KERNEL_VERSION >= 0x050100                          \
> +   || __WORDSIZE == 64                                           \
> +   || (defined __SYSCALL_WORDSIZE && __SYSCALL_WORDSIZE == 64)
> +  return true;
> +# else
> +  return getsockopt_syscall (fd) != -1;
> +# endif
> +#else
> +  return false;
> +#endif
> +}
> --
> 2.30.2
>
>

Re: [PATCH 2/2] linux: Fix ancillary 64-bit time timestamp conversion (BZ #28349, BZ #28350)

[Michael Hudson-Doyle]

I think I experienced this bug while trying to fix systemd-networkd's DHCP6
issues on armhf. But I've lost the test environment now and am not sure I
have the energy to recreate it... Do you plan to backport this to
release/2.34/master?

On Wed, 29 Sept 2021 at 02:40, Adhemerval Zanella via Libc-alpha <
libc-alpha@sourceware.org> wrote:

>
> +
> +/* Check if the extra anciallry space is correctly handled by recvmsg and
>

Typo: ancillary


> +   recvmmsg: if there is no extra space for the 64-bit timestamp the
> syscall
> +   should set MSG_TRUNC flag, otherwise an extra cmsghdr with the
> converted
> +   timestamp is appended at the message control buffer.  */
> +static void
> +do_test_slack_space (void)



>
>
+
> +  /* If there is not timestamp in the ancilliary data, recvmsg should set
> +     the flag inidcating it.  */
>

Typo: indicating. Also probably "if there is *no* timestamp" in the
previous line.


> +  if (!timestamp)
> +    TEST_VERIFY (mmhdr.msg_hdr.msg_flags & MSG_TRUNC);
> +  else
> +    TEST_COMPARE (timestamp, true);
> +  TEST_COMPARE (origdstaddr, true);
> +}
>

Cheers,
mwh

Re: [PATCH 1/2] support: Add support_socket_time64_timestamp

[Adhemerval Zanella]

On 28/09/2021 21:58, Michael Hudson-Doyle via Libc-alpha wrote:
>> +#ifdef __linux__
>> +# include <socket-constants-time64.h>
>> +
>> +static int
>> +__attribute_used__
>> +getsockopt_syscall (int fd)
>>
> 
> I don't find this function name explains what it does very clearly -- maybe
> so_timestamp_new_supported or something like that would be better?

I change to support_socket_so_timestamp_time64() and update the comment to
reflect exact what it checks.

Re: [PATCH 2/2] linux: Fix ancillary 64-bit time timestamp conversion (BZ #28349, BZ #28350)

[Adhemerval Zanella]

On 28/09/2021 22:10, Michael Hudson-Doyle wrote:
> I think I experienced this bug while trying to fix systemd-networkd's DHCP6 issues on armhf. But I've lost the test environment now and am not sure I have the energy to recreate it... Do you plan to backport this to release/2.34/master?

Yes.

> 
> On Wed, 29 Sept 2021 at 02:40, Adhemerval Zanella via Libc-alpha <libc-alpha@sourceware.org <mailto:libc-alpha@sourceware.org>> wrote:
> 
> 
>     +
>     +/* Check if the extra anciallry space is correctly handled by recvmsg and
> 
> 
> Typo: ancillary

Ack.

>  
> 
>     +   recvmmsg: if there is no extra space for the 64-bit timestamp the syscall
>     +   should set MSG_TRUNC flag, otherwise an extra cmsghdr with the converted
>     +   timestamp is appended at the message control buffer.  */
>     +static void
>     +do_test_slack_space (void)
> 
>  
> 
>      
> 
>     +
>     +  /* If there is not timestamp in the ancilliary data, recvmsg should set
>     +     the flag inidcating it.  */
> 
> 
> Typo: indicating. Also probably "if there is *no* timestamp" in the previous line.

Ack.

>  
> 
>     +  if (!timestamp)
>     +    TEST_VERIFY (mmhdr.msg_hdr.msg_flags & MSG_TRUNC);
>     +  else
>     +    TEST_COMPARE (timestamp, true);
>     +  TEST_COMPARE (origdstaddr, true);
>     +}
> 
> 
> Cheers,
> mwh