From 13c51549e2077f2f3bf84e8fd0b46d8b0c615912 Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Mon, 7 Sep 2020 17:08:46 -0300 Subject: linux: Add fallback for 64-bit time_t SO_TIMESTAMP{NS} The recvmsg handling is more complicated because it requires check the returned kernel control message and make some convertions. For !__ASSUME_TIME64_SYSCALLS it converts the first 32-bit time SO_TIMESTAMP or SO_TIMESTAMPNS and appends it to the control buffer if has extra space or returns MSG_CTRUNC otherwise. The 32-bit time field is kept as-is. Calls with __TIMESIZE=32 will see the converted 64-bit time control messages as spurious control message of unknown type. Calls with __TIMESIZE=64 running on pre-time64 kernels will see the original message as a spurious control ones of unknown typ while running on kernel with native 64-bit time support will only see the time64 version of the control message. Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15 kernel). Reviewed-by: Carlos O'Donell Tested-by: Carlos O'Donell --- include/sys/socket.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include') diff --git a/include/sys/socket.h b/include/sys/socket.h index 0e39dd2a3a..38a1f76b3b 100644 --- a/include/sys/socket.h +++ b/include/sys/socket.h @@ -164,5 +164,10 @@ libc_hidden_proto (__libc_sa_len) libc_hidden_proto (__cmsg_nxthdr) +#ifndef __ASSUME_TIME64_SYSCALLS +extern void __convert_scm_timestamps (struct msghdr *msg, socklen_t msgsize) + attribute_hidden; +#endif + #endif #endif -- cgit v1.2.3