From 948ce73b31fdb0860bcec4b8e62b14e88234f98a Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Thu, 27 Jan 2022 16:45:18 -0300 Subject: Linux: Only generate 64 bit timestamps for 64 bit time_t recvmsg/recvmmsg The timestamps created by __convert_scm_timestamps only make sense for 64 bit time_t programs, 32 bit time_t programs will ignore 64 bit time_t timestamps since SO_TIMESTAMP will be defined to old values (either by glibc or kernel headers). Worse, if the buffer is not suffice MSG_CTRUNC is set to indicate it (which breaks some programs [1]). This patch makes only 64 bit time_t recvmsg and recvmmsg to call __convert_scm_timestamps. Also, the assumption to called it is changed from __ASSUME_TIME64_SYSCALLS to __TIMESIZE != 64 since the setsockopt might be called by libraries built without __TIME_BITS=64. The MSG_CTRUNC is only set for the 64 bit symbols, it should happen only if 64 bit time_t programs run older kernels. Checked on x86_64-linux-gnu and i686-linux-gnu. [1] https://github.com/systemd/systemd/pull/20567 Reviewed-by: Florian Weimer --- include/sys/socket.h | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'include/sys/socket.h') diff --git a/include/sys/socket.h b/include/sys/socket.h index a1d749f9fa..6e4cf5077f 100644 --- a/include/sys/socket.h +++ b/include/sys/socket.h @@ -98,15 +98,21 @@ extern int __sendmmsg (int __fd, struct mmsghdr *__vmessages, libc_hidden_proto (__sendmmsg) #endif -/* Receive a message as described by MESSAGE from socket FD. - Returns the number of bytes read or -1 for errors. */ extern ssize_t __libc_recvmsg (int __fd, struct msghdr *__message, int __flags); extern ssize_t __recvmsg (int __fd, struct msghdr *__message, int __flags) attribute_hidden; #if __TIMESIZE == 64 +# define __libc_recvmsg64 __libc_recvmsg +# define __recvmsg64 __recvmsg # define __recvmmsg64 __recvmmsg #else +extern ssize_t __libc_recvmsg64 (int __fd, struct msghdr *__message, + int __flags); +extern ssize_t __recvmsg64 (int __fd, struct msghdr *__message, + int __flags); +/* Receive a message as described by MESSAGE from socket FD. + Returns the number of bytes read or -1 for errors. */ extern int __recvmmsg64 (int __fd, struct mmsghdr *vmessages, unsigned int vlen, int flags, struct __timespec64 *timeout); -- cgit 1.4.1