user/sven/linux.git/include/linux/compat.h, branch v5.5.14

Merge tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground

2019-12-01T22:00:59Z

Pull y2038 cleanups from Arnd Bergmann: "y2038 syscall implementation cleanups This is a series of cleanups for the y2038 work, mostly intended for namespace cleaning: the kernel defines the traditional time_t, timeval and timespec types that often lead to y2038-unsafe code. Even though the unsafe usage is mostly gone from the kernel, having the types and associated functions around means that we can still grow new users, and that we may be missing conversions to safe types that actually matter. There are still a number of driver specific patches needed to get the last users of these types removed, those have been submitted to the respective maintainers" Link: https://lore.kernel.org/lkml/20191108210236.1296047-1-arnd@arndb.de/ * tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (26 commits) y2038: alarm: fix half-second cut-off y2038: ipc: fix x32 ABI breakage y2038: fix typo in powerpc vdso "LOPART" y2038: allow disabling time32 system calls y2038: itimer: change implementation to timespec64 y2038: move itimer reset into itimer.c y2038: use compat_{get,set}_itimer on alpha y2038: itimer: compat handling to itimer.c y2038: time: avoid timespec usage in settimeofday() y2038: timerfd: Use timespec64 internally y2038: elfcore: Use __kernel_old_timeval for process times y2038: make ns_to_compat_timeval use __kernel_old_timeval y2038: socket: use __kernel_old_timespec instead of timespec y2038: socket: remove timespec reference in timestamping y2038: syscalls: change remaining timeval to __kernel_old_timeval y2038: rusage: use __kernel_old_timeval y2038: uapi: change __kernel_time_t to __kernel_old_time_t y2038: stat: avoid 'time_t' in 'struct stat' y2038: ipc: remove __kernel_time_t reference from headers y2038: vdso: powerpc: avoid timespec references ...

futex: Move futex exit handling into futex code

2019-11-20T08:40:07Z

The futex exit handling is #ifdeffed into mm_release() which is not pretty to begin with. But upcoming changes to address futex exit races need to add more functionality to this exit code. Split it out into a function, move it into futex code and make the various futex exit functions static. Preparatory only and no functional change. Folded build fix from Borislav. Signed-off-by: Thomas Gleixner Reviewed-by: Ingo Molnar Acked-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20191106224556.049705556@linutronix.de

y2038: itimer: compat handling to itimer.c

2019-11-15T13:38:30Z

The structure is only used in one place, moving it there simplifies the interface and helps with later changes to this code. Rename it to match the other time32 structures in the process. Reviewed-by: Thomas Gleixner Signed-off-by: Arnd Bergmann

y2038: make ns_to_compat_timeval use __kernel_old_timeval

2019-11-15T13:38:29Z

This gets us one step closer to removing 'struct timeval' from the kernel. We still keep __kernel_old_timeval for interfaces that we cannot fix otherwise, and ns_to_compat_timeval() is provably safe for interfaces that are legitimate users of __kernel_old_timeval on native kernels, so this is an obvious change. Signed-off-by: Arnd Bergmann

signal: simplify set_user_sigmask/restore_user_sigmask

2019-07-17T02:23:24Z

task->saved_sigmask and ->restore_sigmask are only used in the ret-from- syscall paths. This means that set_user_sigmask() can save ->blocked in ->saved_sigmask and do set_restore_sigmask() to indicate that ->blocked was modified. This way the callers do not need 2 sigset_t's passed to set/restore and restore_user_sigmask() renamed to restore_saved_sigmask_unless() turns into the trivial helper which just calls restore_saved_sigmask(). Link: http://lkml.kernel.org/r/20190606113206.GA9464@redhat.com Signed-off-by: Oleg Nesterov Cc: Deepa Dinamani Cc: Arnd Bergmann Cc: Jens Axboe Cc: Davidlohr Bueso Cc: Eric Wong Cc: Jason Baron Cc: Thomas Gleixner Cc: Al Viro Cc: Eric W. Biederman Cc: David Laight Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

y2038: syscalls: rename y2038 compat syscalls

2019-02-06T23:13:27Z

A lot of system calls that pass a time_t somewhere have an implementation using a COMPAT_SYSCALL_DEFINEx() on 64-bit architectures, and have been reworked so that this implementation can now be used on 32-bit architectures as well. The missing step is to redefine them using the regular SYSCALL_DEFINEx() to get them out of the compat namespace and make it possible to build them on 32-bit architectures. Any system call that ends in 'time' gets a '32' suffix on its name for that version, while the others get a '_time32' suffix, to distinguish them from the normal version, which takes a 64-bit time argument in the future. In this step, only 64-bit architectures are changed, doing this rename first lets us avoid touching the 32-bit architectures twice. Acked-by: Catalin Marinas Signed-off-by: Arnd Bergmann

time: make adjtime compat handling available for 32 bit

2019-02-06T23:13:27Z

We want to reuse the compat_timex handling on 32-bit architectures the same way we are using the compat handling for timespec when moving to 64-bit time_t. Move all definitions related to compat_timex out of the compat code into the normal timekeeping code, along with a rename to old_timex32, corresponding to the timespec/timeval structures, and make it controlled by CONFIG_COMPAT_32BIT_TIME, which 32-bit architectures will then select. Signed-off-by: Arnd Bergmann

y2038: signal: Add compat_sys_rt_sigtimedwait_time64

2018-12-18T15:13:04Z

Now that 32-bit architectures have two variants of sys_rt_sigtimedwaid() for 32-bit and 64-bit time_t, we also need to have a second compat system call entry point on the corresponding 64-bit architectures. The traditional system call keeps getting handled by compat_sys_rt_sigtimedwait(), and this adds a new compat_sys_rt_sigtimedwait_time64() that differs only in the timeout argument type. The naming remains a bit asymmetric for the moment. Ideally we would want to have compat_sys_rt_sigtimedwait_time32() for the old version and compat_sys_rt_sigtimedwait() for the new one to mirror the names of the native entry points, but renaming the existing system call tables causes unnecessary churn. I would suggest renaming all such system calls together at a later point. Signed-off-by: Arnd Bergmann

y2038: socket: Add compat_sys_recvmmsg_time64

2018-12-18T15:13:04Z

recvmmsg() takes two arguments to pointers of structures that differ between 32-bit and 64-bit architectures: mmsghdr and timespec. For y2038 compatbility, we are changing the native system call from timespec to __kernel_timespec with a 64-bit time_t (in another patch), and use the existing compat system call on both 32-bit and 64-bit architectures for compatibility with traditional 32-bit user space. As we now have two variants of recvmmsg() for 32-bit tasks that are both different from the variant that we use on 64-bit tasks, this means we also require two compat system calls! The solution I picked is to flip things around: The existing compat_sys_recvmmsg() call gets moved from net/compat.c into net/socket.c and now handles the case for old user space on all architectures that have set CONFIG_COMPAT_32BIT_TIME. A new compat_sys_recvmmsg_time64() call gets added in the old place for 64-bit architectures only, this one handles the case of a compat mmsghdr structure combined with __kernel_timespec. In the indirect sys_socketcall(), we now need to call either do_sys_recvmmsg() or __compat_sys_recvmmsg(), depending on what kind of architecture we are on. For compat_sys_socketcall(), no such change is needed, we always call __compat_sys_recvmmsg(). I decided to not add a new SYS_RECVMMSG_TIME64 socketcall: Any libc implementation for 64-bit time_t will need significant changes including an updated asm/unistd.h, and it seems better to consistently use the separate syscalls that configuration, leaving the socketcall only for backward compatibility with 32-bit time_t based libc. The naming is asymmetric for the moment, so both existing syscalls entry points keep their names, while the new ones are recvmmsg_time32 and compat_recvmmsg_time64 respectively. I expect that we will rename the compat syscalls later as we start using generated syscall tables everywhere and add these entry points. Signed-off-by: Arnd Bergmann

io_pgetevents: use __kernel_timespec

2018-12-06T16:23:31Z

struct timespec is not y2038 safe. struct __kernel_timespec is the new y2038 safe structure for all syscalls that are using struct timespec. Update io_pgetevents interfaces to use struct __kernel_timespec. sigset_t also has different representations on 32 bit and 64 bit architectures. Hence, we need to support the following different syscalls: New y2038 safe syscalls: (Controlled by CONFIG_64BIT_TIME for 32 bit ABIs) Native 64 bit(unchanged) and native 32 bit : sys_io_pgetevents Compat : compat_sys_io_pgetevents_time64 Older y2038 unsafe syscalls: (Controlled by CONFIG_32BIT_COMPAT_TIME for 32 bit ABIs) Native 32 bit : sys_io_pgetevents_time32 Compat : compat_sys_io_pgetevents Note that io_getevents syscalls do not have a y2038 safe solution. Signed-off-by: Deepa Dinamani Signed-off-by: Arnd Bergmann