Sargun Dhillon 8649c322f7 pid: Implement pidfd_getfd syscall ... This syscall allows for the retrieval of file descriptors from other processes, based on their pidfd. This is possible using ptrace, and injection of parasitic code to inject code which leverages SCM_RIGHTS to move file descriptors between a tracee and a tracer. Unfortunately, ptrace comes with a high cost of requiring the process to be stopped, and breaks debuggers. This does not require stopping the process under manipulation. One reason to use this is to allow sandboxers to take actions on file descriptors on the behalf of another process. For example, this can be combined with seccomp-bpf's user notification to do on-demand fd extraction and take privileged actions. One such privileged action is binding a socket to a privileged port. /* prototype */ /* flags is currently reserved and should be set to 0 */ int sys_pidfd_getfd(int pidfd, int fd, unsigned int flags); /* testing */ Ran self-test suite on x86_64 Signed-off-by: Sargun Dhillon <sargun@sargun.me> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20200107175927.4558-3-sargun@sargun.me Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>		2020-01-13 21:49:36 +01:00
..
bpf	bpf: Fix precision tracking for unbounded scalars	2019-12-22 17:21:10 -08:00
cgroup	Merge branch 'for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup	2019-11-25 19:23:46 -08:00
configs
debug	kdb: Tweak escape handling for vi users	2019-10-28 12:08:29 +00:00
dma	lib/genalloc.c: rename addr_in_gen_pool to gen_pool_has_addr	2019-12-04 19:44:13 -08:00
events	perf/core: Add SRCU annotation for pmus list walk	2019-12-17 13:32:46 +01:00
gcov
irq	irqchip updates for Linux 5.5	2019-11-20 14:16:34 +01:00
livepatch	New tracing features:	2019-11-27 11:42:01 -08:00
locking	Revert "locking/mutex: Complain upon mutex API misuse in IRQ contexts"	2019-12-11 00:27:43 +01:00
power	Additional power management updates for 5.5-rc1	2019-12-04 10:48:09 -08:00
printk	Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2019-12-03 09:29:50 -08:00
rcu	Merge branches 'doc.2019.10.29a', 'fixes.2019.10.30a', 'nohz.2019.10.28a', 'replace.2019.10.30a', 'torture.2019.10.05a' and 'lkmm.2019.10.05a' into HEAD	2019-10-30 08:47:13 -07:00
sched	Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2019-12-21 10:52:10 -08:00
time	ptp: fix the race between the release of ptp_clock and cdev	2019-12-30 20:19:27 -08:00
trace	tracing: Fix endianness bug in histogram trigger	2019-12-21 16:08:59 -05:00
.gitignore
acct.c
async.c
audit.c	audit: remove redundant condition check in kauditd_thread()	2019-10-25 11:48:14 -04:00
audit.h
audit_fsnotify.c
audit_tree.c
audit_watch.c	audit_get_nd(): don't unlock parent too early	2019-11-10 11:56:55 -05:00
auditfilter.c
auditsc.c	Revert "bpf: Emit audit messages upon successful prog load and unload"	2019-11-23 09:56:02 -08:00
backtracetest.c
bounds.c
capability.c
compat.c	y2038: itimer: compat handling to itimer.c	2019-11-15 14:38:30 +01:00
configs.c
context_tracking.c	context_tracking: Rename context_tracking_is_enabled() => context_tracking_enabled()	2019-10-29 10:01:12 +01:00
cpu.c	Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2019-11-26 16:02:40 -08:00
cpu_pm.c
crash_core.c
crash_dump.c
cred.c	memcg: account security cred as well to kmemcg	2020-01-04 13:55:09 -08:00
delayacct.c
dma.c
elfcore.c	kernel/elfcore.c: include proper prototypes	2019-09-25 17:51:39 -07:00
exec_domain.c
exit.c	for-linus-2020-01-03	2020-01-03 11:17:14 -08:00
extable.c	bpf: Add support for BTF pointers to x86 JIT	2019-10-17 16:44:36 +02:00
fail_function.c
fork.c	Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2019-12-03 12:20:25 -08:00
freezer.c	Revert "libata, freezer: avoid block device removal while system is frozen"	2019-10-06 09:11:37 -06:00
futex.c	futex: Prevent exit livelock	2019-11-20 09:40:38 +01:00
gen_kheaders.sh	kheaders: explain why include/config/autoconf.h is excluded from md5sum	2019-11-11 20:10:01 +09:00
groups.c
hung_task.c
iomem.c
irq_work.c	irq_work: Fix IRQ_WORK_BUSY bit clearing	2019-11-15 10:48:37 +01:00
jump_label.c
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt	sched/Kconfig: Fix spelling mistake in user-visible help text	2019-11-12 11:35:32 +01:00
kcov.c	kcov: remote coverage support	2019-12-04 19:44:14 -08:00
kexec.c
kexec_core.c	kexec: bail out upon SIGKILL when allocating memory.	2019-09-25 17:51:40 -07:00
kexec_elf.c
kexec_file.c	kexec: Fix pointer-to-int-cast warnings	2019-11-01 21:42:58 +01:00
kexec_internal.h
kheaders.c
kmod.c
kprobes.c	Tracing updates:	2019-09-20 11:19:48 -07:00
ksysfs.c
kthread.c	kthread: make __kthread_queue_delayed_work static	2019-10-16 09:20:58 -07:00
latencytop.c
Makefile	Kbuild updates for v5.5	2019-12-02 17:35:04 -08:00
module-internal.h
module.c	This contains 3 changes:	2019-12-11 12:22:38 -08:00
module_signature.c
module_signing.c
notifier.c	kernel/notifier.c: remove blocking_notifier_chain_cond_register()	2019-12-04 19:44:12 -08:00
nsproxy.c
padata.c
panic.c	locking/refcount: Remove unused 'refcount_error_report()' function	2019-11-25 09:15:42 +01:00
params.c
pid.c	pid: Implement pidfd_getfd syscall	2020-01-13 21:49:36 +01:00
pid_namespace.c	fork: extend clone3() to support setting a PID	2019-11-15 23:49:22 +01:00
profile.c	kernel/profile.c: use cpumask_available to check for NULL cpumask	2019-12-04 19:44:12 -08:00
ptrace.c
range.c
reboot.c
relay.c
resource.c	mm/memory_hotplug.c: use PFN_UP / PFN_DOWN in walk_system_ram_range()	2019-09-24 15:54:09 -07:00
rseq.c
seccomp.c	seccomp: Check that seccomp_notif is zeroed out by the user	2020-01-02 13:03:45 -08:00
signal.c	cgroup: freezer: call cgroup_enter_frozen() with preemption disabled in ptrace_stop()	2019-10-11 08:39:57 -07:00
smp.c
smpboot.c
smpboot.h
softirq.c
stackleak.c
stacktrace.c	stacktrace: Get rid of unneeded '!!' pattern	2019-11-11 10:30:59 +01:00
stop_machine.c	Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu	2019-10-31 09:33:19 +01:00
sys.c	kernel/sys.c: avoid copying possible padding bytes in copy_to_user	2019-12-04 19:44:12 -08:00
sys_ni.c	y2038: allow disabling time32 system calls	2019-11-15 14:38:30 +01:00
sysctl-test.c	kernel/sysctl-test: Add null pointer test for sysctl.c:proc_dointvec()	2019-09-30 17:35:01 -06:00
sysctl.c	kernel: sysctl: make drop_caches write-only	2019-12-01 12:59:07 -08:00
sysctl_binary.c	sysctl: Remove the sysctl system call	2019-11-26 13:03:56 -06:00
task_work.c
taskstats.c	taskstats: fix data-race	2019-12-04 15:18:39 +01:00
test_kprobes.c
torture.c
tracepoint.c
tsacct.c
ucount.c
uid16.c
uid16.h
umh.c
up.c
user-return-notifier.c
user.c
user_namespace.c
utsname.c
utsname_sysctl.c
watchdog.c
watchdog_hld.c
workqueue.c	workqueue: Use pr_warn instead of pr_warning	2019-12-06 09:59:30 +01:00
workqueue_internal.h