diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2019-04-17 22:56:11 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-04-19 14:07:40 -0700 |
| commit | 0768e17073dc527ccd18ed5f96ce85f9985e9115 (patch) | |
| tree | 4f9898446f998dd34bd56f5329dcc4bbd97f92d5 /include | |
| parent | 5ce5d8a5a4ae64b281bea7ae028c960f12acae21 (diff) | |
net: socket: implement 64-bit timestamps
The 'timeval' and 'timespec' data structures used for socket timestamps
are going to be redefined in user space based on 64-bit time_t in future
versions of the C library to deal with the y2038 overflow problem,
which breaks the ABI definition.
Unlike many modern ioctl commands, SIOCGSTAMP and SIOCGSTAMPNS do not
use the _IOR() macro to encode the size of the transferred data, so it
remains ambiguous whether the application uses the old or new layout.
The best workaround I could find is rather ugly: we redefine the command
code based on the size of the respective data structure with a ternary
operator. This lets it get evaluated as late as possible, hopefully after
that structure is visible to the caller. We cannot use an #ifdef here,
because inux/sockios.h might have been included before any libc header
that could determine the size of time_t.
The ioctl implementation now interprets the new command codes as always
referring to the 64-bit structure on all architectures, while the old
architecture specific command code still refers to the old architecture
specific layout. The new command number is only used when they are
actually different.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/uapi/asm-generic/sockios.h | 4 | ||||
| -rw-r--r-- | include/uapi/linux/sockios.h | 21 |
2 files changed, 23 insertions, 2 deletions
diff --git a/include/uapi/asm-generic/sockios.h b/include/uapi/asm-generic/sockios.h index 64f658c7cec2..44fa3ed70483 100644 --- a/include/uapi/asm-generic/sockios.h +++ b/include/uapi/asm-generic/sockios.h @@ -8,7 +8,7 @@ #define FIOGETOWN 0x8903 #define SIOCGPGRP 0x8904 #define SIOCATMARK 0x8905 -#define SIOCGSTAMP 0x8906 /* Get stamp (timeval) */ -#define SIOCGSTAMPNS 0x8907 /* Get stamp (timespec) */ +#define SIOCGSTAMP_OLD 0x8906 /* Get stamp (timeval) */ +#define SIOCGSTAMPNS_OLD 0x8907 /* Get stamp (timespec) */ #endif /* __ASM_GENERIC_SOCKIOS_H */ diff --git a/include/uapi/linux/sockios.h b/include/uapi/linux/sockios.h index d393e9ed3964..7d1bccbbef78 100644 --- a/include/uapi/linux/sockios.h +++ b/include/uapi/linux/sockios.h @@ -19,6 +19,7 @@ #ifndef _LINUX_SOCKIOS_H #define _LINUX_SOCKIOS_H +#include <asm/bitsperlong.h> #include <asm/sockios.h> /* Linux-specific socket ioctls */ @@ -27,6 +28,26 @@ #define SOCK_IOC_TYPE 0x89 +/* + * the timeval/timespec data structure layout is defined by libc, + * so we need to cover both possible versions on 32-bit. + */ +/* Get stamp (timeval) */ +#define SIOCGSTAMP_NEW _IOR(SOCK_IOC_TYPE, 0x06, long long[2]) +/* Get stamp (timespec) */ +#define SIOCGSTAMPNS_NEW _IOR(SOCK_IOC_TYPE, 0x07, long long[2]) + +#if __BITS_PER_LONG == 64 || (defined(__x86_64__) && defined(__ILP32__)) +/* on 64-bit and x32, avoid the ?: operator */ +#define SIOCGSTAMP SIOCGSTAMP_OLD +#define SIOCGSTAMPNS SIOCGSTAMPNS_OLD +#else +#define SIOCGSTAMP ((sizeof(struct timeval)) == 8 ? \ + SIOCGSTAMP_OLD : SIOCGSTAMP_NEW) +#define SIOCGSTAMPNS ((sizeof(struct timespec)) == 8 ? \ + SIOCGSTAMPNS_OLD : SIOCGSTAMPNS_NEW) +#endif + /* Routing table calls. */ #define SIOCADDRT 0x890B /* add routing table entry */ #define SIOCDELRT 0x890C /* delete routing table entry */ |