Andrii Nakryiko 1a80dbcb2d bpf: support deferring bpf_link dealloc to after RCU grace period ... BPF link for some program types is passed as a "context" which can be used by those BPF programs to look up additional information. E.g., for multi-kprobes and multi-uprobes, link is used to fetch BPF cookie values. Because of this runtime dependency, when bpf_link refcnt drops to zero there could still be active BPF programs running accessing link data. This patch adds generic support to defer bpf_link dealloc callback to after RCU GP, if requested. This is done by exposing two different deallocation callbacks, one synchronous and one deferred. If deferred one is provided, bpf_link_free() will schedule dealloc_deferred() callback to happen after RCU GP. BPF is using two flavors of RCU: "classic" non-sleepable one and RCU tasks trace one. The latter is used when sleepable BPF programs are used. bpf_link_free() accommodates that by checking underlying BPF program's sleepable flag, and goes either through normal RCU GP only for non-sleepable, or through RCU tasks trace GP *and* then normal RCU GP (taking into account rcu_trace_implies_rcu_gp() optimization), if BPF program is sleepable. We use this for multi-kprobe and multi-uprobe links, which dereference link during program run. We also preventively switch raw_tp link to use deferred dealloc callback, as upcoming changes in bpf-next tree expose raw_tp link data (specifically, cookie value) to BPF program at runtime as well. Fixes: 0dcac27254 ("bpf: Add multi kprobe link") Fixes: 89ae89f53d ("bpf: Add multi uprobe link") Reported-by: syzbot+981935d9485a560bfbcb@syzkaller.appspotmail.com Reported-by: syzbot+2cb5a6c573e98db598cc@syzkaller.appspotmail.com Reported-by: syzbot+62d8b26793e8a2bd0516@syzkaller.appspotmail.com Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20240328052426.3042617-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>		2024-03-28 18:47:45 -07:00
..
bpf	bpf: support deferring bpf_link dealloc to after RCU grace period	2024-03-28 18:47:45 -07:00
cgroup	Networking changes for 6.9.	2024-03-12 17:44:08 -07:00
configs	Networking changes for 6.9.	2024-03-12 17:44:08 -07:00
debug	kdb: Fix a potential buffer overflow in kdb_local()	2024-01-17 17:19:06 +00:00
dma	dma-mapping fixes for Linux 6.9	2024-03-24 10:45:31 -07:00
entry	entry: Respect changes to system call number by trace_sys_enter()	2024-03-12 13:23:32 +01:00
events	- Sumanth Korikkar has taught s390 to allocate hotplug-time page frames	2024-03-14 17:43:30 -07:00
futex	futex: Prevent the reuse of stale pi_state	2024-01-19 12:58:17 +01:00
gcov	gcov: annotate struct gcov_iterator with __counted_by	2023-10-18 14:43:22 -07:00
irq	Updates for the MSI interrupt subsystem and RISC-V initial MSI support:	2024-03-11 14:03:03 -07:00
kcsan	mm: delete checks for xor_unlock_is_negative_byte()	2023-10-18 14:34:17 -07:00
livepatch	livepatch: Fix missing newline character in klp_resolve_symbols()	2023-09-20 11:24:18 +02:00
locking	locking/rtmutex: Use try_cmpxchg_relaxed() in mark_rt_mutex_waiters()	2024-03-01 13:02:05 +01:00
module	This push fixes a regression that broke iwd as well as a divide by	2024-03-25 10:48:23 -07:00
power	RTC for 6.9	2024-03-21 17:16:46 -07:00
printk	printk changes for 6.9-rc2	2024-03-26 09:25:57 -07:00
rcu	Merge branches 'rcu-doc.2024.02.14a', 'rcu-nocb.2024.02.14a', 'rcu-exp.2024.02.14a', 'rcu-tasks.2024.02.26a' and 'rcu-misc.2024.02.14a' into rcu.2024.02.26a	2024-02-26 17:37:25 -08:00
sched	RISC-V Patches for the 6.9 Merge Window	2024-03-22 10:41:13 -07:00
time	Fix memory leak in posix_clock_open()	2024-03-27 09:03:22 -07:00
trace	bpf: support deferring bpf_link dealloc to after RCU grace period	2024-03-28 18:47:45 -07:00
.gitignore
acct.c	fs: rename __mnt_{want,drop}_write*() helpers	2023-09-11 15:05:50 +02:00
async.c	async: Use a dedicated unbound workqueue with raised min_active	2024-02-09 11:13:59 -10:00
audit_fsnotify.c
audit_tree.c	As usual, lots of singleton and doubleton patches all over the tree and	2023-11-02 20:53:31 -10:00
audit_watch.c	audit: don't WARN_ON_ONCE(!current->mm) in audit_exe_compare()	2023-11-14 17:34:27 -05:00
audit.c	audit: use KMEM_CACHE() instead of kmem_cache_create()	2024-01-25 10:12:22 -05:00
audit.h	audit: correct audit_filter_inodes() definition	2023-07-21 12:17:25 -04:00
auditfilter.c	audit: remove unnecessary assignment in audit_dupe_lsm_field()	2024-01-25 09:59:27 -05:00
auditsc.c	audit,io_uring: io_uring openat triggers audit reference count underflow	2023-10-13 18:34:46 +02:00
backtracetest.c	backtracetest: Convert from tasklet to BH workqueue	2024-02-05 13:22:34 -10:00
bounds.c	bounds: support non-power-of-two CONFIG_NR_CPUS	2024-02-22 15:38:51 -08:00
capability.c	lsm: constify the 'target' parameter in security_capget()	2023-08-08 16:48:47 -04:00
cfi.c
compat.c
configs.c
context_tracking.c	context_tracking: Fix kerneldoc headers for __ct_user_{enter,exit}()	2024-02-14 07:53:50 -08:00
cpu_pm.c
cpu.c	Rework of APIC enumeration and topology evaluation:	2024-03-11 15:45:55 -07:00
crash_core.c	crash: split crash dumping code out from kexec_core.c	2024-02-23 17:48:22 -08:00
crash_reserve.c	crash: use macro to add crashk_res into iomem early for specific arch	2024-03-26 11:14:12 -07:00
cred.c	cred: Use KMEM_CACHE() instead of kmem_cache_create()	2024-02-23 17:33:31 -05:00
delayacct.c
dma.c
elfcorehdr.c	crash: remove dependency of FA_DUMP on CRASH_DUMP	2024-02-23 17:48:22 -08:00
exec_domain.c
exit.c	vfs-6.9.pidfd	2024-03-11 10:21:06 -07:00
exit.h	exit: add internal include file with helpers	2023-09-21 12:03:50 -06:00
extable.c
fail_function.c
fork.c	RCU pull request for v6.9	2024-03-11 12:02:50 -07:00
freezer.c	Linux 6.7-rc6	2023-12-23 15:52:13 +01:00
gen_kheaders.sh	Revert "kheaders: substituting --sort in archive creation"	2023-05-28 16:20:21 +09:00
groups.c	groups: Convert group_info.usage to refcount_t	2023-09-29 11:28:39 -07:00
hung_task.c	kernel/hung_task.c: export sysctl_hung_task_timeout_secs	2024-03-13 21:22:04 -04:00
iomem.c	kernel/iomem.c: remove __weak ioremap_cache helper	2023-08-21 13:37:28 -07:00
irq_work.c
jump_label.c
kallsyms_internal.h
kallsyms_selftest.c	mm/vmalloc: remove vmap_area_list	2024-02-23 17:48:19 -08:00
kallsyms_selftest.h
kallsyms.c	kallsyms: Change func signature for cleanup_symbol_name()	2023-08-25 15:00:36 -07:00
kcmp.c	file: convert to SLAB_TYPESAFE_BY_RCU	2023-10-19 11:02:48 +02:00
Kconfig.freezer
Kconfig.hz
Kconfig.kexec	crash: clean up kdump related config items	2024-02-23 17:48:22 -08:00
Kconfig.locks
Kconfig.preempt
kcov.c	kcov: add prototypes for helper functions	2023-06-09 17:44:17 -07:00
kexec_core.c	- Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min	2024-03-14 18:03:09 -07:00
kexec_elf.c
kexec_file.c	arm64, crash: wrap crash dumping code into crash related ifdefs	2024-02-23 17:48:23 -08:00
kexec_internal.h	crash: remove dependency of FA_DUMP on CRASH_DUMP	2024-02-23 17:48:22 -08:00
kexec.c	crash: split crash dumping code out from kexec_core.c	2024-02-23 17:48:22 -08:00
kheaders.c
kprobes.c	kprobes: Remove unnecessary initial values of variables	2024-02-08 23:29:29 +09:00
ksyms_common.c	kallsyms: make kallsyms_show_value() as generic function	2023-06-08 12:27:20 -07:00
ksysfs.c	Driver core changes for 6.9-rc1	2024-03-21 13:34:15 -07:00
kthread.c	As usual, lots of singleton and doubleton patches all over the tree and	2023-11-02 20:53:31 -10:00
latencytop.c
Makefile	crash: split crash dumping code out from kexec_core.c	2024-02-23 17:48:22 -08:00
module_signature.c
notifier.c
nsproxy.c	pidfd: add pidfs	2024-03-01 12:23:37 +01:00
numa.c	kernel/numa.c: Move logging out of numa.h	2023-12-20 19:26:30 -05:00
padata.c	Author: Gang Li padata: dispatch works on	2024-03-06 13:04:17 -08:00
panic.c	- Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min	2024-03-14 18:03:09 -07:00
params.c	params: Fix multi-line comment style	2023-12-01 09:51:44 -08:00
pid_namespace.c	wait: Remove uapi header file from main header file	2023-12-20 19:26:31 -05:00
pid_sysctl.h	memfd: replace ratcheting feature from vm.memfd_noexec with hierarchy	2023-08-21 13:37:59 -07:00
pid.c	pidfs: remove config option	2024-03-13 12:53:53 -07:00
profile.c
ptrace.c	ptrace_attach: shift send(SIGSTOP) into ptrace_set_stopped()	2024-02-22 15:38:52 -08:00
range.c
reboot.c	Thermal control updates for 6.8-rc1	2024-01-09 16:20:17 -08:00
regset.c
relay.c	kernel: relay: remove relay_file_splice_read dead code, doesn't work	2023-12-29 12:22:27 -08:00
resource_kunit.c
resource.c	Quite a lot of kexec work this time around. Many singleton patches in	2024-01-09 11:46:20 -08:00
rseq.c
scftorture.c	scftorture: Pause testing after memory-allocation failure	2023-07-14 15:02:57 -07:00
scs.c
seccomp.c	file: remove __receive_fd()	2023-12-12 14:24:14 +01:00
signal.c	- Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min	2024-03-14 18:03:09 -07:00
smp.c	CSD lock commits for v6.7	2023-10-30 17:56:53 -10:00
smpboot.c	kthread: add kthread_stop_put	2023-10-04 10:41:57 -07:00
smpboot.h
softirq.c	workqueue: Drain BH work items on hot-unplugged CPUs	2024-02-29 11:51:24 -10:00
stackleak.c
stacktrace.c	stacktrace: fix kernel-doc typo	2023-12-29 12:22:29 -08:00
static_call_inline.c
static_call.c
stop_machine.c
sys_ni.c	lsm/stable-6.8 PR 20240105	2024-01-09 12:57:46 -08:00
sys.c	prctl: generalize PR_SET_MDWE support check to be per-arch	2024-03-26 11:07:22 -07:00
sysctl-test.c
sysctl.c	tracing: Support to dump instance traces by ftrace_dump_on_oops	2024-03-18 10:33:06 -04:00
task_work.c	task_work: add kerneldoc annotation for 'data' argument	2023-09-19 13:21:32 -07:00
taskstats.c	taskstats: fill_stats_for_tgid: use for_each_thread()	2023-10-04 10:41:57 -07:00
torture.c	torture: Print out torture module parameters	2023-09-24 17:24:01 +02:00
tracepoint.c
tsacct.c
ucount.c	sysctl: Add size to register_sysctl	2023-08-15 15:26:17 -07:00
uid16.c
uid16.h
umh.c	sysctl: fix unused proc_cap_handler() function warning	2023-06-29 15:19:43 -07:00
up.c	smp: Change function signatures to use call_single_data_t	2023-09-13 14:59:24 +02:00
user_namespace.c	user_namespace: remove unnecessary NULL values from kbuf	2024-02-22 15:38:52 -08:00
user-return-notifier.c
user.c	binfmt_misc: enable sandboxed mounts	2023-10-11 08:46:01 -07:00
usermode_driver.c
utsname_sysctl.c
utsname.c
vhost_task.c	vhost: Fix worker hangs due to missed wake up calls	2023-06-08 15:43:09 -04:00
vmcore_info.c	crash_core: export vmemmap when CONFIG_SPARSEMEM_VMEMMAP is enabled	2024-03-04 17:01:27 -08:00
watch_queue.c	watch_queue: fix kcalloc() arguments order	2023-12-21 13:17:54 +01:00
watchdog_buddy.c	watchdog/hardlockup: move SMP barriers from common code to buddy code	2023-06-19 16:25:28 -07:00
watchdog_perf.c	watchdog/perf: add a weak function for an arch to detect if perf can use NMIs	2023-06-09 17:44:21 -07:00
watchdog.c	watchdog/core: remove sysctl handlers from public header	2024-03-12 13:09:23 -07:00
workqueue_internal.h	workqueue: Drop the special locking rule for worker->flags and worker_pool->flags	2023-08-07 15:57:22 -10:00
workqueue.c	Driver core changes for 6.9-rc1	2024-03-21 13:34:15 -07:00