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Dmitrii Banshchikov 439b99314b bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs 
commit 5e0bc3082e2e403ac0753e099c2b01446bb35578 upstream.

Use of bpf_ktime_get_coarse_ns() and bpf_timer_* helpers in tracing
progs may result in locking issues.

bpf_ktime_get_coarse_ns() uses ktime_get_coarse_ns() time accessor that
isn't safe for any context:
======================================================
WARNING: possible circular locking dependency detected
5.15.0-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.4/14877 is trying to acquire lock:
ffffffff8cb30008 (tk_core.seq.seqcount){----}-{0:0}, at: ktime_get_coarse_ts64+0x25/0x110 kernel/time/timekeeping.c:2255

but task is already holding lock:
ffffffff90dbf200 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_deactivate+0x61/0x400 lib/debugobjects.c:735

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&obj_hash[i].lock){-.-.}-{2:2}:
       lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       __debug_object_init+0xd9/0x1860 lib/debugobjects.c:569
       debug_hrtimer_init kernel/time/hrtimer.c:414 [inline]
       debug_init kernel/time/hrtimer.c:468 [inline]
       hrtimer_init+0x20/0x40 kernel/time/hrtimer.c:1592
       ntp_init_cmos_sync kernel/time/ntp.c:676 [inline]
       ntp_init+0xa1/0xad kernel/time/ntp.c:1095
       timekeeping_init+0x512/0x6bf kernel/time/timekeeping.c:1639
       start_kernel+0x267/0x56e init/main.c:1030
       secondary_startup_64_no_verify+0xb1/0xbb

-> #0 (tk_core.seq.seqcount){----}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3051 [inline]
       check_prevs_add kernel/locking/lockdep.c:3174 [inline]
       validate_chain+0x1dfb/0x8240 kernel/locking/lockdep.c:3789
       __lock_acquire+0x1382/0x2b00 kernel/locking/lockdep.c:5015
       lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625
       seqcount_lockdep_reader_access+0xfe/0x230 include/linux/seqlock.h:103
       ktime_get_coarse_ts64+0x25/0x110 kernel/time/timekeeping.c:2255
       ktime_get_coarse include/linux/timekeeping.h:120 [inline]
       ktime_get_coarse_ns include/linux/timekeeping.h:126 [inline]
       ____bpf_ktime_get_coarse_ns kernel/bpf/helpers.c:173 [inline]
       bpf_ktime_get_coarse_ns+0x7e/0x130 kernel/bpf/helpers.c:171
       bpf_prog_a99735ebafdda2f1+0x10/0xb50
       bpf_dispatcher_nop_func include/linux/bpf.h:721 [inline]
       __bpf_prog_run include/linux/filter.h:626 [inline]
       bpf_prog_run include/linux/filter.h:633 [inline]
       BPF_PROG_RUN_ARRAY include/linux/bpf.h:1294 [inline]
       trace_call_bpf+0x2cf/0x5d0 kernel/trace/bpf_trace.c:127
       perf_trace_run_bpf_submit+0x7b/0x1d0 kernel/events/core.c:9708
       perf_trace_lock+0x37c/0x440 include/trace/events/lock.h:39
       trace_lock_release+0x128/0x150 include/trace/events/lock.h:58
       lock_release+0x82/0x810 kernel/locking/lockdep.c:5636
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
       _raw_spin_unlock_irqrestore+0x75/0x130 kernel/locking/spinlock.c:194
       debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
       debug_deactivate kernel/time/hrtimer.c:481 [inline]
       __run_hrtimer kernel/time/hrtimer.c:1653 [inline]
       __hrtimer_run_queues+0x2f9/0xa60 kernel/time/hrtimer.c:1749
       hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811
       local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
       __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103
       sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097
       asm_sysvec_apic_timer_interrupt+0x12/0x20
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
       _raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
       try_to_wake_up+0x702/0xd20 kernel/sched/core.c:4118
       wake_up_process kernel/sched/core.c:4200 [inline]
       wake_up_q+0x9a/0xf0 kernel/sched/core.c:953
       futex_wake+0x50f/0x5b0 kernel/futex/waitwake.c:184
       do_futex+0x367/0x560 kernel/futex/syscalls.c:127
       __do_sys_futex kernel/futex/syscalls.c:199 [inline]
       __se_sys_futex+0x401/0x4b0 kernel/futex/syscalls.c:180
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x44/0xae

There is a possible deadlock with bpf_timer_* set of helpers:
hrtimer_start()
  lock_base();
  trace_hrtimer...()
    perf_event()
      bpf_run()
        bpf_timer_start()
          hrtimer_start()
            lock_base()         <- DEADLOCK

Forbid use of bpf_ktime_get_coarse_ns() and bpf_timer_* helpers in
BPF_PROG_TYPE_KPROBE, BPF_PROG_TYPE_TRACEPOINT, BPF_PROG_TYPE_PERF_EVENT
and BPF_PROG_TYPE_RAW_TRACEPOINT prog types.

Fixes: d05512618056 ("bpf: Add bpf_ktime_get_coarse_ns helper")
Fixes: b00628b1c7d5 ("bpf: Introduce bpf timers.")
Reported-by: syzbot+43fd005b5a1b4d10781e@syzkaller.appspotmail.com
Signed-off-by: Dmitrii Banshchikov <me@ubique.spb.ru>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211113142227.566439-2-me@ubique.spb.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25 09:49:07 +01:00
..
bpf
bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs
2021-11-25 09:49:07 +01:00
cgroup
cgroup: Fix rootcg cpu.stat guest double counting
2021-11-18 19:16:45 +01:00
configs
drivers/char: remove /dev/kmem for good
2021-05-07 00:26:34 -07:00
debug
kdb: Adopt scheduler's task classification
2021-11-18 19:17:06 +01:00
dma
dma-mapping fixes for Linux 5.15
2021-10-20 10:16:51 -10:00
entry
signal: Replace force_fatal_sig with force_exit_sig when in doubt
2021-11-25 09:49:07 +01:00
events
perf/core: Avoid put_page() when GUP fails
2021-11-21 13:44:14 +01:00
gcov
Kconfig: Introduce ARCH_WANTS_NO_INSTR and CC_HAS_NO_PROFILE_FN_ATTR
2021-06-22 11:07:18 -07:00
irq
PCI/MSI: Move non-mask check back into low level accessors
2021-11-18 19:17:14 +01:00
kcsan
LKMM updates:
2021-09-02 13:00:15 -07:00
livepatch
livepatch: Replace deprecated CPU-hotplug functions.
2021-08-19 12:00:24 +02:00
locking
lockdep: Let lock_is_held_type() detect recursive read as read
2021-11-18 19:16:23 +01:00
power
PM: hibernate: fix sparse warnings
2021-11-18 19:16:38 +01:00
printk
printk: restore flushing of NMI buffers on remote CPUs after NMI backtraces
2021-11-25 09:48:45 +01:00
rcu
rcu: Fix rcu_dynticks_curr_cpu_in_eqs() vs noinstr
2021-11-18 19:16:30 +01:00
sched
sched/fair: Prevent dead task groups from regaining cfs_rq's
2021-11-25 09:48:32 +01:00
time
posix-cpu-timers: Clear task::posix_cputimers_work in copy_process()
2021-11-18 19:17:14 +01:00
trace
bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs
2021-11-25 09:49:07 +01:00
.gitignore
.gitignore: prefix local generated files with a slash
2021-05-02 00:43:35 +09:00
acct.c
kernel/acct.c: use dedicated helper to access rlimit values
2021-09-08 11:50:26 -07:00
async.c
kernel/async.c: remove async_unregister_domain()
2021-05-07 00:26:33 -07:00
audit_fsnotify.c
audit_alloc_mark(): don't open-code ERR_CAST()
2021-02-23 10:25:27 -05:00
audit_tree.c
audit: move put_tree() to avoid trim_trees refcount underflow and UAF
2021-08-24 18:52:36 -04:00
audit_watch.c
fsnotify: generalize handle_inode_event()
2020-12-03 14:58:35 +01:00
audit.c
lsm: separate security_task_getsecid() into subjective and objective variants
2021-03-22 15:23:32 -04:00
audit.h
audit: add header protection to kernel/audit.h
2021-07-19 22:38:24 -04:00
auditfilter.c
lsm: separate security_task_getsecid() into subjective and objective variants
2021-03-22 15:23:32 -04:00
auditsc.c
audit: fix possible null-pointer dereference in audit_filter_rules
2021-10-18 18:27:47 -04:00
backtracetest.c
…
bounds.c
…
capability.c
capability: handle idmapped mounts
2021-01-24 14:27:16 +01:00
cfi.c
cfi: Use rcu_read_{un}lock_sched_notrace
2021-08-11 13:11:12 -07:00
compat.c
arch: remove compat_alloc_user_space
2021-09-08 15:32:35 -07:00
configs.c
…
context_tracking.c
…
cpu_pm.c
PM: cpu: Make notifier chain use a raw_spinlock_t
2021-08-16 18:55:32 +02:00
cpu.c
cpu/hotplug: Add debug printks for hotplug callback failures
2021-08-10 18:31:32 +02:00
crash_core.c
kdump: use vmlinux_build_id to simplify
2021-07-08 11:48:22 -07:00
crash_dump.c
…
cred.c
ucounts: Move get_ucounts from cred_alloc_blank to key_change_session_keyring
2021-10-20 10:34:20 -05:00
delayacct.c
delayacct: Add sysctl to enable at runtime
2021-05-12 11:43:25 +02:00
dma.c
…
exec_domain.c
…
exit.c
io_uring: remove files pointer in cancellation functions
2021-08-23 13:10:37 -06:00
extable.c
…
fail_function.c
fault-injection: handle EI_ETYPE_TRUE
2020-12-15 22:46:19 -08:00
fork.c
posix-cpu-timers: Clear task::posix_cputimers_work in copy_process()
2021-11-18 19:17:14 +01:00
freezer.c
sched: Add get_current_state()
2021-06-18 11:43:08 +02:00
futex.c
futex: Remove unused variable 'vpid' in futex_proxy_trylock_atomic()
2021-09-03 23:00:22 +02:00
gen_kheaders.sh
kbuild: clean up ${quiet} checks in shell scripts
2021-05-27 04:01:50 +09:00
groups.c
groups: simplify struct group_info allocation
2021-02-26 09:41:03 -08:00
hung_task.c
Merge branch 'akpm' (patches from Andrew)
2021-07-02 12:08:10 -07:00
iomem.c
…
irq_work.c
irq_work: Make irq_work_queue() NMI-safe again
2021-06-10 10:00:08 +02:00
jump_label.c
jump_label: Fix jump_label_text_reserved() vs __init
2021-07-05 10:46:20 +02:00
kallsyms.c
module: add printk formats to add module build ID to stacktraces
2021-07-08 11:48:22 -07:00
kcmp.c
Merge branch 'exec-update-lock-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2020-12-15 19:36:48 -08:00
Kconfig.freezer
…
Kconfig.hz
…
Kconfig.locks
locking/rwlock: Provide RT variant
2021-08-17 17:50:51 +02:00
Kconfig.preempt
sched/core: Disable CONFIG_SCHED_CORE by default
2021-06-28 22:43:05 +02:00
kcov.c
…
kexec_core.c
Merge branch 'rework/printk_safe-removal' into for-linus
2021-08-30 16:36:10 +02:00
kexec_elf.c
…
kexec_file.c
kernel: kexec_file: fix error return code of kexec_calculate_store_digests()
2021-05-07 00:26:32 -07:00
kexec_internal.h
kexec: move machine_kexec_post_load() to public interface
2021-02-22 12:33:26 +00:00
kexec.c
kexec: avoid compat_alloc_user_space
2021-09-08 15:32:34 -07:00
kheaders.c
…
kmod.c
modules: add CONFIG_MODPROBE_PATH
2021-05-07 00:26:33 -07:00
kprobes.c
kprobes: Do not use local variable when creating debugfs file
2021-11-18 19:16:29 +01:00
ksysfs.c
…
kthread.c
Merge branch 'akpm' (patches from Andrew)
2021-06-29 17:29:11 -07:00
latencytop.c
…
Makefile
kbuild: update config_data.gz only when the content of .config is changed
2021-05-02 00:43:35 +09:00
module_signature.c
module: harden ELF info handling
2021-01-19 10:24:45 +01:00
module_signing.c
module: harden ELF info handling
2021-01-19 10:24:45 +01:00
module-internal.h
…
module.c
module: fix clang CFI with MODULE_UNLOAD=n
2021-09-28 12:56:26 +02:00
notifier.c
notifier: Remove atomic_notifier_call_chain_robust()
2021-08-16 18:55:32 +02:00
nsproxy.c
memcg: enable accounting for new namesapces and struct nsproxy
2021-09-03 09:58:12 -07:00
padata.c
padata: Remove repeated verbose license text
2021-08-27 16:30:18 +08:00
panic.c
Merge branch 'rework/printk_safe-removal' into for-linus
2021-08-30 16:36:10 +02:00
params.c
params: lift param_set_uint_minmax to common code
2021-08-16 14:42:22 +02:00
pid_namespace.c
memcg: enable accounting for new namesapces and struct nsproxy
2021-09-03 09:58:12 -07:00
pid.c
kernel/pid.c: implement additional checks upon pidfd_create() parameters
2021-08-10 12:53:07 +02:00
profile.c
profiling: fix shift-out-of-bounds bugs
2021-09-08 11:50:26 -07:00
ptrace.c
sched: Change task_struct::state
2021-06-18 11:43:09 +02:00
range.c
…
reboot.c
reboot: Add hardware protection power-off
2021-06-21 13:08:36 +01:00
regset.c
…
relay.c
relay: allow the use of const callback structs
2020-12-15 22:46:18 -08:00
resource_kunit.c
resource: provide meaningful MODULE_LICENSE() in test suite
2020-11-25 18:52:35 +01:00
resource.c
kernel/resource: fix return code check in __request_free_mem_region
2021-05-14 19:41:32 -07:00
rseq.c
KVM: rseq: Update rseq when processing NOTIFY_RESUME on xfer to KVM guest
2021-09-22 10:24:01 -04:00
scftorture.c
scftorture: Avoid NULL pointer exception on early exit
2021-07-27 11:39:30 -07:00
scs.c
scs: Release kasan vmalloc poison in scs_free process
2021-11-18 19:16:29 +01:00
seccomp.c
Merge branch 'exit-cleanups-for-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2021-09-01 14:52:05 -07:00
signal.c
signal: Replace force_fatal_sig with force_exit_sig when in doubt
2021-11-25 09:49:07 +01:00
smp.c
smp: Fix all kernel-doc warnings
2021-08-11 14:47:16 +02:00
smpboot.c
smpboot: Replace deprecated CPU-hotplug functions.
2021-08-10 14:57:42 +02:00
smpboot.h
…
softirq.c
genirq: Change force_irqthreads to a static key
2021-08-10 22:50:07 +02:00
stackleak.c
…
stacktrace.c
…
static_call.c
static_call: Fix static_call_text_reserved() vs __init
2021-07-05 10:46:33 +02:00
stop_machine.c
stop_machine: Add caller debug info to queue_stop_cpus_work
2021-03-23 16:01:58 +01:00
sys_ni.c
compat: remove some compat entry points
2021-09-08 15:32:35 -07:00
sys.c
Merge branch 'akpm' (patches from Andrew)
2021-09-08 12:55:35 -07:00
sysctl-test.c
kernel/sysctl-test: Remove some casts which are no-longer required
2021-06-23 16:41:24 -06:00
sysctl.c
Merge branch 'akpm' (patches from Andrew)
2021-09-03 10:08:28 -07:00
task_work.c
kasan: record task_work_add() call stack
2021-04-30 11:20:42 -07:00
taskstats.c
treewide: rename nla_strlcpy to nla_strscpy.
2020-11-16 08:08:54 -08:00
test_kprobes.c
…
torture.c
torture: Replace deprecated CPU-hotplug functions.
2021-08-10 10:48:07 -07:00
tracepoint.c
tracepoint: Fix kerneldoc comments
2021-08-16 11:39:51 -04:00
tsacct.c
…
ucount.c
ucounts: Fix signal ucount refcounting
2021-10-18 16:02:30 -05:00
uid16.c
…
uid16.h
…
umh.c
kernel/umh.c: fix some spelling mistakes
2021-05-07 00:26:34 -07:00
up.c
A set of locking related fixes and updates:
2021-05-09 13:07:03 -07:00
user_namespace.c
memcg: enable accounting for new namesapces and struct nsproxy
2021-09-03 09:58:12 -07:00
user-return-notifier.c
…
user.c
fs/epoll: use a per-cpu counter for user's watches count
2021-09-08 11:50:27 -07:00
usermode_driver.c
Merge branch 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2021-07-03 11:41:14 -07:00
utsname_sysctl.c
…
utsname.c
…
watch_queue.c
watch_queue: rectify kernel-doc for init_watch()
2021-01-26 11:16:34 +00:00
watchdog_hld.c
…
watchdog.c
kernel: watchdog: modify the explanation related to watchdog thread
2021-06-29 10:53:46 -07:00
workqueue_internal.h
workqueue: Assign a color to barrier work items
2021-08-17 07:49:10 -10:00
workqueue.c
workqueue: make sysfs of unbound kworker cpumask more clever
2021-11-18 19:16:17 +01:00