Andrii Nakryiko af6eea5743 bpf: Implement bpf_link-based cgroup BPF program attachment ... Implement new sub-command to attach cgroup BPF programs and return FD-based bpf_link back on success. bpf_link, once attached to cgroup, cannot be replaced, except by owner having its FD. Cgroup bpf_link supports only BPF_F_ALLOW_MULTI semantics. Both link-based and prog-based BPF_F_ALLOW_MULTI attachments can be freely intermixed. To prevent bpf_cgroup_link from keeping cgroup alive past the point when no BPF program can be executed, implement auto-detachment of link. When cgroup_bpf_release() is called, all attached bpf_links are forced to release cgroup refcounts, but they leave bpf_link otherwise active and allocated, as well as still owning underlying bpf_prog. This is because user-space might still have FDs open and active, so bpf_link as a user-referenced object can't be freed yet. Once last active FD is closed, bpf_link will be freed and underlying bpf_prog refcount will be dropped. But cgroup refcount won't be touched, because cgroup is released already. The inherent race between bpf_cgroup_link release (from closing last FD) and cgroup_bpf_release() is resolved by both operations taking cgroup_mutex. So the only additional check required is when bpf_cgroup_link attempts to detach itself from cgroup. At that time we need to check whether there is still cgroup associated with that link. And if not, exit with success, because bpf_cgroup_link was already successfully detached. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Roman Gushchin <guro@fb.com> Link: https://lore.kernel.org/bpf/20200330030001.2312810-2-andriin@fb.com		2020-03-30 17:35:59 -07:00
..
bpf	bpf: Implement bpf_link-based cgroup BPF program attachment	2020-03-30 17:35:59 -07:00
cgroup	bpf: Implement bpf_link-based cgroup BPF program attachment	2020-03-30 17:35:59 -07:00
configs	kvm_config: add CONFIG_VIRTIO_MENU	2018-10-24 20:55:56 -04:00
debug	Revert "kdb: Get rid of confusing diag msg from "rd" if current task has no regs"	2020-02-06 11:40:09 +00:00
dma	dma-direct: improve DMA mask overflow reporting	2020-02-05 18:53:41 +01:00
events	bpf: Add name to struct bpf_ksym	2020-03-13 12:49:51 -07:00
gcov	Revert "um: Enable CONFIG_CONSTRUCTORS"	2020-01-19 22:42:06 +01:00
irq	genirq/proc: Reject invalid affinity masks (again)	2020-02-14 09:43:17 +01:00
livepatch	New tracing features:	2019-11-27 11:42:01 -08:00
locking	proc: convert everything to "struct proc_ops"	2020-02-04 03:05:26 +00:00
power	PM / hibernate: fix typo "reserverd_size" -> "reserved_size"	2020-02-20 11:58:01 +01:00
printk	printk: fix exclusive_console replaying	2020-01-02 16:15:04 +01:00
rcu	rcu: Forgive slow expedited grace periods at boot time	2020-01-25 12:00:40 -08:00
sched	sched/fair: Fix statistics for find_idlest_group()	2020-02-27 10:08:27 +01:00
time	y2038: remove unused time32 interfaces	2020-02-21 11:22:15 -08:00
trace	bpf: Introduce BPF_PROG_TYPE_LSM	2020-03-30 01:34:00 +02:00
.gitignore	Provide in-kernel headers to make extending kernel easier	2019-04-29 16:48:03 +02:00
acct.c	acct: stop using get_seconds()	2019-12-18 18:07:31 +01:00
async.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441	2019-06-05 17:37:17 +02:00
audit_fsnotify.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157	2019-05-30 11:26:37 -07:00
audit_tree.c	fsnotify: switch send_to_group() and ->handle_event to const struct qstr *	2019-04-26 13:51:03 -04:00
audit_watch.c	audit_get_nd(): don't unlock parent too early	2019-11-10 11:56:55 -05:00
audit.c	audit: always check the netlink payload length in audit_receive_msg()	2020-02-24 16:38:57 -05:00
audit.h	audit/stable-5.3 PR 20190702	2019-07-08 18:55:42 -07:00
auditfilter.c	audit: fix error handling in audit_data_to_entry()	2020-02-22 20:36:47 -05:00
auditsc.c	Revert "bpf: Emit audit messages upon successful prog load and unload"	2019-11-23 09:56:02 -08:00
backtracetest.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441	2019-06-05 17:37:17 +02:00
bounds.c	kbuild: fix kernel/bounds.c 'W=1' warning	2018-10-31 08:54:14 -07:00
capability.c	LSM: add SafeSetID module that gates setid calls	2019-01-25 11:22:43 -08:00
compat.c	y2038: remove unused time32 interfaces	2020-02-21 11:22:15 -08:00
configs.c	proc: convert everything to "struct proc_ops"	2020-02-04 03:05:26 +00:00
context_tracking.c	context_tracking: Rename context_tracking_is_enabled() => context_tracking_enabled()	2019-10-29 10:01:12 +01:00
cpu_pm.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282	2019-06-05 17:36:37 +02:00
cpu.c	Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2020-01-28 10:07:09 -08:00
crash_core.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230	2019-06-19 17:09:06 +02:00
crash_dump.c	treewide: Add SPDX license identifier for missed files	2019-05-21 10:50:45 +02:00
cred.c	Merge branch 'dhowells' (patches from DavidH)	2020-01-14 09:56:31 -08:00
delayacct.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 25	2019-05-21 11:52:39 +02:00
dma.c
elfcore.c	kernel/elfcore.c: include proper prototypes	2019-09-25 17:51:39 -07:00
exec_domain.c
exit.c	exit: Fix Sparse errors and warnings	2020-02-28 13:34:39 +01:00
extable.c	bpf: Remove bpf_image tree	2020-03-13 12:49:52 -07:00
fail_function.c	fail_function: no need to check return value of debugfs_create functions	2019-06-03 15:49:06 +02:00
fork.c	fork: Use RCU_INIT_POINTER() instead of rcu_access_pointer()	2020-02-28 13:34:36 +01:00
freezer.c	Revert "libata, freezer: avoid block device removal while system is frozen"	2019-10-06 09:11:37 -06:00
futex.c	futex: Fix kernel-doc notation warning	2020-01-09 13:23:40 +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	treewide: Add SPDX license identifier for missed files	2019-05-21 10:50:45 +02:00
iomem.c	mm/nvdimm: add is_ioremap_addr and use that to check ioremap address	2019-07-12 11:05:40 -07:00
irq_work.c	irq_work: Fix IRQ_WORK_BUSY bit clearing	2019-11-15 10:48:37 +01:00
jump_label.c	jump_label: Don't warn on __exit jump entries	2019-08-29 15:10:10 +01:00
kallsyms.c	Kbuild updates for v5.6 (2nd)	2020-02-09 16:05:50 -08:00
kcmp.c
Kconfig.freezer	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Kconfig.hz	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Kconfig.locks	sched/rt, locking: Use CONFIG_PREEMPTION	2019-12-08 14:37:36 +01:00
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_core.c	kexec: add machine_kexec_post_load()	2020-01-08 16:32:55 +00:00
kexec_elf.c	kexec_elf: support 32 bit ELF files	2019-09-06 23:58:44 +02:00
kexec_file.c	kexec: add machine_kexec_post_load()	2020-01-08 16:32:55 +00:00
kexec_internal.h	kexec: add machine_kexec_post_load()	2020-01-08 16:32:55 +00:00
kexec.c	kexec: add machine_kexec_post_load()	2020-01-08 16:32:55 +00:00
kheaders.c	kheaders: Move from proc to sysfs	2019-05-24 20:16:01 +02:00
kmod.c
kprobes.c	kprobes: Fix optimize_kprobe()/unoptimize_kprobe() cancellation logic	2020-01-09 12:40:13 +01:00
ksysfs.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 170	2019-05-30 11:26:39 -07:00
kthread.c	kthread: make __kthread_queue_delayed_work static	2019-10-16 09:20:58 -07:00
latencytop.c	proc: convert everything to "struct proc_ops"	2020-02-04 03:05:26 +00:00
Makefile	kcov: ignore fault-inject and stacktrace	2020-01-31 10:30:41 -08:00
module_signature.c	MODSIGN: Export module signature definitions	2019-08-05 18:39:56 -04:00
module_signing.c	MODSIGN: Export module signature definitions	2019-08-05 18:39:56 -04:00
module-internal.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36	2019-05-24 17:27:11 +02:00
module.c	proc: convert everything to "struct proc_ops"	2020-02-04 03:05:26 +00:00
notifier.c	kernel/notifier.c: remove blocking_notifier_chain_cond_register()	2019-12-04 19:44:12 -08:00
nsproxy.c	ns: Introduce Time Namespace	2020-01-14 12:20:48 +01:00
padata.c	padata: update documentation	2019-12-11 16:37:02 +08:00
panic.c	locking/refcount: Remove unused 'refcount_error_report()' function	2019-11-25 09:15:42 +01:00
params.c	lockdown: Lock down module params that specify hardware parameters (eg. ioport)	2019-08-19 21:54:16 -07:00
pid_namespace.c	fork: extend clone3() to support setting a PID	2019-11-15 23:49:22 +01:00
pid.c	pid: make ENOMEM return value more obvious	2020-03-09 23:40:05 +01:00
profile.c	proc: convert everything to "struct proc_ops"	2020-02-04 03:05:26 +00:00
ptrace.c	ptrace: reintroduce usage of subjective credentials in ptrace_has_cap()	2020-01-18 13:51:39 +01:00
range.c
reboot.c	treewide: Add SPDX license identifier for missed files	2019-05-21 10:50:45 +02:00
relay.c	Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2019-03-12 13:27:20 -07:00
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	rseq: Reject unknown flags on rseq unregister	2019-12-25 10:41:20 +01:00
seccomp.c	bpf: Use bpf_prog_run_pin_on_cpu() at simple call sites.	2020-02-24 16:20:09 -08:00
signal.c	signal: avoid double atomic counter increments for user accounting	2020-02-26 09:54:03 -08:00
smp.c	smp: Remove superfluous cond_func check in smp_call_function_many_cond()	2020-01-28 15:43:00 +01:00
smpboot.c	treewide: Add SPDX license identifier for missed files	2019-05-21 10:50:45 +02:00
smpboot.h
softirq.c	Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2019-07-08 11:01:13 -07:00
stackleak.c	stackleak: Mark stackleak_track_stack() as notrace	2018-12-05 19:31:44 -08:00
stacktrace.c	stacktrace: Get rid of unneeded '!!' pattern	2019-11-11 10:30:59 +01:00
stop_machine.c	stop_machine: Make stop_cpus() static	2020-01-17 10:19:21 +01:00
sys_ni.c	y2038: allow disabling time32 system calls	2019-11-15 14:38:30 +01:00
sys.c	prctl: PR_{G,S}ET_IO_FLUSHER to support controlling memory reclaim	2020-01-28 10:09:51 +01:00
sysctl_binary.c	sysctl: Remove the sysctl system call	2019-11-26 13:03:56 -06:00
sysctl-test.c	kunit: allow kunit tests to be loaded as a module	2020-01-09 16:42:29 -07:00
sysctl.c	s390: remove obsolete ieee_emulation_warnings	2020-02-19 13:51:46 +01:00
task_work.c
taskstats.c	taskstats: fix data-race	2019-12-04 15:18:39 +01:00
test_kprobes.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 25	2019-05-21 11:52:39 +02:00
torture.c	torture: Remove exporting of internal functions	2019-08-01 14:30:22 -07:00
tracepoint.c	The main changes in this release include:	2019-07-18 11:51:00 -07:00
tsacct.c	tsacct: add 64-bit btime field	2019-12-18 18:07:31 +01:00
ucount.c	proc/sysctl: add shared variables for range check	2019-07-18 17:08:07 -07:00
uid16.c
uid16.h
umh.c	treewide: Add SPDX license identifier for missed files	2019-05-21 10:50:45 +02:00
up.c	smp/up: Make smp_call_function_single() match SMP semantics	2020-02-07 15:34:12 +01:00
user_namespace.c	Keyrings namespacing	2019-07-08 19:36:47 -07:00
user-return-notifier.c	treewide: Add SPDX license identifier for missed files	2019-05-21 10:50:45 +02:00
user.c	Keyrings namespacing	2019-07-08 19:36:47 -07:00
utsname_sysctl.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441	2019-06-05 17:37:17 +02:00
utsname.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441	2019-06-05 17:37:17 +02:00
watchdog_hld.c	kernel/watchdog_hld.c: hard lockup message should end with a newline	2019-04-19 09:46:05 -07:00
watchdog.c	watchdog/softlockup: Enforce that timestamp is valid on boot	2020-01-17 11:19:22 +01:00
workqueue_internal.h	sched/core, workqueues: Distangle worker accounting from rq lock	2019-04-16 16:55:15 +02:00
workqueue.c	workqueue: don't use wq_select_unbound_cpu() for bound works	2020-03-10 10:30:51 -04:00