David Herrmann 0ee5dc31c7 shm: add memfd_create() syscall ... memfd_create() is similar to mmap(MAP_ANON), but returns a file-descriptor that you can pass to mmap(). It can support sealing and avoids any connection to user-visible mount-points. Thus, it's not subject to quotas on mounted file-systems, but can be used like malloc()'ed memory, but with a file-descriptor to it. memfd_create() returns the raw shmem file, so calls like ftruncate() can be used to modify the underlying inode. Also calls like fstat() will return proper information and mark the file as regular file. If you want sealing, you can specify MFD_ALLOW_SEALING. Otherwise, sealing is not supported (like on all other regular files). Compared to O_TMPFILE, it does not require a tmpfs mount-point and is not subject to a filesystem size limit. It is still properly accounted to memcg limits, though, and to the same overcommit or no-overcommit accounting as all user memory. Signed-off-by: David Herrmann <dh.herrmann@gmail.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Ryan Lortie <desrt@desrt.ca> Cc: Lennart Poettering <lennart@poettering.net> Cc: Daniel Mack <zonque@gmail.com> Cc: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Change-Id: I1ce97f3a4b9723e8ed1ff99697212c75db4fd0bd		2020-01-22 21:32:52 +01:00
..
debug	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
events	perf/hwbp: Simplify the perf-hwbp code, fix documentation	2020-01-22 21:32:06 +01:00
gcov
irq	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
power	power: reduce timeout for stopping processes	2019-10-18 22:26:40 +02:00
sched	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
time	alarmtimer: Prevent overflow for relative nanosleep	2019-08-09 12:03:09 +02:00
trace	UPSTREAM: ring-buffer: Prevent overflow of size in ring_buffer_resize()	2019-08-06 12:24:25 +02:00
.gitignore
acct.c
async.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
audit.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
audit.h
audit_tree.c	VFS: Make clone_mnt()/copy_tree()/collect_mounts() return errors	2019-08-06 10:44:11 +02:00
audit_watch.c	get rid of kern_path_parent()	2019-08-06 10:44:16 +02:00
auditfilter.c
auditsc.c	seccomp: remove duplicated failure logging	2019-08-05 14:22:29 +02:00
backtracetest.c
bounds.c
capability.c
cgroup.c	Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0	2019-08-06 11:41:21 +02:00
cgroup_freezer.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
compat.c
configs.c
cpu.c	CPU hotplug: Provide lockless versions of callback registration functions	2019-08-05 14:22:43 +02:00
cpu_pm.c
cpuset.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
crash_dump.c
cred.c
delayacct.c
dma.c
elfcore.c
exec_domain.c	Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0	2019-08-06 11:41:21 +02:00
exit.c	Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0	2019-08-06 11:41:21 +02:00
extable.c
fork.c	Revert "proc: smaps: Allow smaps access for CAP_SYS_RESOURCE"	2019-08-06 12:26:28 +02:00
freezer.c	Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0	2019-08-06 11:41:21 +02:00
futex.c	futex: Remove unnecessary warning from get_futex_key	2019-08-08 16:37:20 +02:00
futex_compat.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
groups.c	misc: Import SM-G900H kernel source code	2019-08-02 15:14:10 +02:00
hrtimer.c	time: Remove CONFIG_TIMER_STATS	2019-08-06 12:26:30 +02:00
hung_task.c
irq_work.c
itimer.c
jump_label.c
kallsyms.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c
kfifo.c	misc: Import SM-G900H kernel source code	2019-08-02 15:14:10 +02:00
kmod.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
kprobes.c
ksysfs.c	rcu: Add a module parameter to force use of expedited RCU primitives	2014-05-05 15:49:18 -07:00
kthread.c
latencytop.c
lglock.c	brlocks/lglocks: turn into functions	2019-08-06 10:41:58 +02:00
lockdep.c	Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0	2019-08-06 11:41:21 +02:00
lockdep_internals.h
lockdep_proc.c
lockdep_states.h
Makefile	brlocks/lglocks: turn into functions	2019-08-06 10:41:58 +02:00
module.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
mutex-debug.c
mutex-debug.h
mutex.c	misc: Import SM-G900H kernel source code	2019-08-02 15:14:10 +02:00
mutex.h
notifier.c
nsproxy.c	userns: make each net (net_ns) belong to a user_ns	2019-08-08 15:08:49 +02:00
padata.c
panic.c	misc: Allow kernel to be compiled with SEC_DEBUG disabled	2019-08-09 09:59:25 +02:00
params.c
pid.c	misc: Import SM-G900H kernel source code	2019-08-02 15:14:10 +02:00
pid_namespace.c	proc: Usable inode numbers for the namespace file descriptors.	2015-09-11 14:44:24 +05:30
posix-cpu-timers.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
posix-timers.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
printk.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
profile.c
ptrace.c	__ptrace_may_access() should not deny sub-threads	2019-08-06 08:48:40 +02:00
range.c
rcu.h	rcu: Add a module parameter to force use of expedited RCU primitives	2014-05-05 15:49:18 -07:00
rcupdate.c	rcu: Make exit_rcu() more precise and consolidate	2014-07-21 21:31:55 +05:30
rcutiny.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
rcutiny_plugin.h	rcu: Make exit_rcu() more precise and consolidate	2014-07-21 21:31:55 +05:30
rcutorture.c
rcutree.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
rcutree.h	Revert "rcu: Move PREEMPT_RCU preemption to switch_to() invocation"	2014-07-21 21:46:54 +05:30
rcutree_plugin.h	Revert "rcu: Move PREEMPT_RCU preemption to switch_to() invocation"	2014-07-21 21:46:54 +05:30
rcutree_trace.c	rcu: Make rcu_barrier() less disruptive	2014-07-21 21:37:29 +05:30
relay.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
res_counter.c
resource.c	/proc/iomem: only expose physical resource addresses to privileged users	2019-08-09 11:48:51 +02:00
rtmutex-debug.c
rtmutex-debug.h	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
rtmutex-tester.c
rtmutex.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
rtmutex.h	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
rtmutex_common.h
rwsem.c
seccomp.c	seccomp: Replace BUG(!spin_is_locked()) with assert_spin_lock	2019-08-05 14:22:42 +02:00
semaphore.c
signal.c	Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0	2019-08-06 11:41:21 +02:00
smp.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
softirq.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
spinlock.c
srcu.c
stacktrace.c
stop_machine.c	Drop whitespace, Kconfigs, Makefile noise and dead code	2013-03-14 09:32:58 -07:00
sys.c	userns: Add kuid_t and kgid_t and associated infrastructure in uidgid.h	2019-08-08 15:08:48 +02:00
sys_ni.c	shm: add memfd_create() syscall	2020-01-22 21:32:52 +01:00
sysctl.c	add toggle for disabling newly added USB devices	2019-08-09 12:02:50 +02:00
sysctl_binary.c	kernel/sysctl_binary.c: check name array length in deprecated_sysctl_warning()	2019-08-08 12:09:29 +02:00
taskstats.c
test_kprobes.c
time.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
timeconst.bc	kernel: Replace timeconst.pl with a bc script	2019-08-05 09:09:45 +02:00
timeconst.pl	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
timer.c	time: Remove CONFIG_TIMER_STATS	2019-08-06 12:26:30 +02:00
tracepoint.c	Merge tag 'v3.4.113' into lineage-16.0	2019-08-05 14:20:47 +02:00
tsacct.c
uid16.c
up.c
user-return-notifier.c
user.c	proc: Usable inode numbers for the namespace file descriptors.	2015-09-11 14:44:24 +05:30
user_namespace.c	proc: fix build broken by proc inode per namespace patch	2019-08-05 09:13:23 +02:00
utsname.c	proc: Usable inode numbers for the namespace file descriptors.	2015-09-11 14:44:24 +05:30
utsname_sysctl.c
wait.c
watchdog.c	Merge remote-tracking branch 'google-common/deprecated/android-3.4' into lineage-16.0	2019-08-06 11:41:21 +02:00
workqueue.c	time: Remove CONFIG_TIMER_STATS	2019-08-06 12:26:30 +02:00
workqueue_sched.h