Eric Dumazet f32935bcfd tick/sched: Annotate lockless access to last_jiffies_update ... commit de95a991bb upstream. syzbot (KCSAN) reported a data-race in tick_do_update_jiffies64(): BUG: KCSAN: data-race in tick_do_update_jiffies64 / tick_do_update_jiffies64 write to 0xffffffff8603d008 of 8 bytes by interrupt on cpu 1: tick_do_update_jiffies64+0x100/0x250 kernel/time/tick-sched.c:73 tick_sched_do_timer+0xd4/0xe0 kernel/time/tick-sched.c:138 tick_sched_timer+0x43/0xe0 kernel/time/tick-sched.c:1292 __run_hrtimer kernel/time/hrtimer.c:1514 [inline] __hrtimer_run_queues+0x274/0x5f0 kernel/time/hrtimer.c:1576 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1638 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline] smp_apic_timer_interrupt+0xdc/0x280 arch/x86/kernel/apic/apic.c:1135 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 arch_local_irq_restore arch/x86/include/asm/paravirt.h:756 [inline] kcsan_setup_watchpoint+0x1d4/0x460 kernel/kcsan/core.c:436 check_access kernel/kcsan/core.c:466 [inline] __tsan_read1 kernel/kcsan/core.c:593 [inline] __tsan_read1+0xc2/0x100 kernel/kcsan/core.c:593 kallsyms_expand_symbol.constprop.0+0x70/0x160 kernel/kallsyms.c:79 kallsyms_lookup_name+0x7f/0x120 kernel/kallsyms.c:170 insert_report_filterlist kernel/kcsan/debugfs.c:155 [inline] debugfs_write+0x14b/0x2d0 kernel/kcsan/debugfs.c:256 full_proxy_write+0xbd/0x100 fs/debugfs/file.c:225 __vfs_write+0x67/0xc0 fs/read_write.c:494 vfs_write fs/read_write.c:558 [inline] vfs_write+0x18a/0x390 fs/read_write.c:542 ksys_write+0xd5/0x1b0 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write fs/read_write.c:620 [inline] __x64_sys_write+0x4c/0x60 fs/read_write.c:620 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffffffff8603d008 of 8 bytes by task 0 on cpu 0: tick_do_update_jiffies64+0x2b/0x250 kernel/time/tick-sched.c:62 tick_nohz_update_jiffies kernel/time/tick-sched.c:505 [inline] tick_nohz_irq_enter kernel/time/tick-sched.c:1257 [inline] tick_irq_enter+0x139/0x1c0 kernel/time/tick-sched.c:1274 irq_enter+0x4f/0x60 kernel/softirq.c:354 entering_irq arch/x86/include/asm/apic.h:517 [inline] entering_ack_irq arch/x86/include/asm/apic.h:523 [inline] smp_apic_timer_interrupt+0x55/0x280 arch/x86/kernel/apic/apic.c:1133 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:571 default_idle_call+0x1e/0x40 kernel/sched/idle.c:94 cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x1af/0x280 kernel/sched/idle.c:263 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:355 rest_init+0xec/0xf6 init/main.c:452 arch_call_rest_init+0x17/0x37 start_kernel+0x838/0x85e init/main.c:786 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:490 x86_64_start_kernel+0x72/0x76 arch/x86/kernel/head64.c:471 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc7+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Use READ_ONCE() and WRITE_ONCE() to annotate this expected race. Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20191205045619.204946-1-edumazet@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-01-23 08:20:35 +01:00
..
bpf	bpf: Fix passing modified ctx to ld/abs/ind instruction	2020-01-12 12:12:02 +01:00
cgroup	cgroup: pids: use atomic64_t for pids->limit	2019-12-17 20:39:29 +01:00
configs	ANDROID: binder: add hwbinder,vndbinder to BINDER_DEVICES.	2017-08-22 18:43:23 -07:00
debug	kdb: Don't back trace on a cpu that didn't round up	2019-02-12 19:46:09 +01:00
events	signal: Properly deliver SIGILL from uprobes	2019-11-20 17:59:52 +01:00
gcov	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
irq	genirq: Prevent NULL pointer dereference in resend_irqs()	2019-09-19 09:08:04 +02:00
livepatch	livepatch: Nullify obj->mod in klp_module_coming()'s error path	2019-10-07 18:55:09 +02:00
locking	locking/spinlock/debug: Fix various data races	2020-01-12 12:11:49 +01:00
power	PM / hibernate: memory_bm_find_bit(): Tighten node optimisation	2020-01-09 10:17:53 +01:00
printk	printk: fix integer overflow in setup_log_buf()	2019-12-01 09:13:17 +01:00
rcu	rcuperf: Fix cleanup path for invalid perf_type strings	2019-05-31 06:47:33 -07:00
sched	sched/fair: Scale bandwidth quota and period without losing quota/period ratio precision	2019-12-17 20:38:43 +01:00
time	tick/sched: Annotate lockless access to last_jiffies_update	2020-01-23 08:20:35 +01:00
trace	tracing: Have stack tracer compile when MCOUNT_INSN_SIZE is not defined	2020-01-14 20:05:40 +01:00
.gitignore
acct.c	kernel/acct.c: fix the acct->needcheck check in check_free_space()	2018-01-10 09:31:17 +01:00
async.c	kernel/async.c: revert "async: simplify lowest_in_progress()"	2018-02-16 20:23:05 +01:00
audit.c	audit: return on memory error to avoid null pointer dereference	2018-05-30 07:52:39 +02:00
audit.h	ipc: mqueue: Replace timespec with timespec64	2017-09-03 20:21:24 -04:00
audit_fsnotify.c
audit_tree.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
audit_watch.c	audit_get_nd(): don't unlock parent too early	2019-12-17 20:37:27 +01:00
auditfilter.c	audit: fix a memory leak bug	2019-05-31 06:47:25 -07:00
auditsc.c	audit: print empty EXECVE args	2019-12-01 09:14:03 +01:00
backtracetest.c
bounds.c	kbuild: fix kernel/bounds.c 'W=1' warning	2018-11-13 11:15:08 -08:00
capability.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
compat.c	compat: fix 4-byte infoleak via uninitialized struct field	2018-05-16 10:10:26 +02:00
configs.c
context_tracking.c
cpu.c	cpu/SMT: State SMT is disabled even with nosmt and without "=force"	2019-11-24 08:23:08 +01:00
cpu_pm.c
crash_core.c	kdump: write correct address of mem_section into vmcoreinfo	2018-01-17 09:45:27 +01:00
crash_dump.c
cred.c	memcg: account security cred as well to kmemcg	2020-01-09 10:17:54 +01:00
delayacct.c	delayacct: Use raw_spinlocks	2018-08-03 07:50:38 +02:00
dma.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
elfcore.c	kernel/elfcore.c: include proper prototypes	2019-10-11 18:18:42 +02:00
exec_domain.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
exit.c	exit: panic before exit_mm() on global init exit	2020-01-09 10:17:56 +01:00
extable.c	extable: Enable RCU if it is not watching in kernel_text_address()	2017-09-23 16:50:20 -04:00
fork.c	futex: Split futex_mm_release() for exit/exec	2019-12-05 15:38:26 +01:00
freezer.c
futex.c	futex: Prevent exit livelock	2019-12-05 15:38:28 +01:00
groups.c	kernel: make groups_sort calling a responsibility group_info allocators	2017-12-20 10:10:18 +01:00
hung_task.c	kernel: hung_task.c: disable on suspend	2019-04-20 09:15:05 +02:00
irq_work.c
jump_label.c	sched/core: Fix cpu.max vs. cpuhotplug deadlock	2018-12-05 19:41:17 +01:00
kallsyms.c	kallsyms: Don't let kallsyms_lookup_size_offset() fail on retrieving the first symbol	2019-09-21 07:15:38 +02:00
kcmp.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c	kcov: ensure irq code sees a valid area	2018-08-03 07:50:22 +02:00
kexec.c
kexec_core.c	kexec: Allocate decrypted control pages for kdump if SME is enabled	2019-11-24 08:23:15 +01:00
kexec_file.c
kexec_internal.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
kmod.c	kmod: move #ifdef CONFIG_MODULES wrapper to Makefile	2017-09-08 18:26:51 -07:00
kprobes.c	kprobes: Don't call BUG_ON() if there is a kprobe in use on free list	2019-11-20 17:59:56 +01:00
ksysfs.c
kthread.c	kthread, tracing: Don't expose half-written comm when creating kthreads	2018-08-03 07:50:21 +02:00
latencytop.c
Makefile	y2038: futex: Move compat implementation into futex.c	2019-12-05 15:38:22 +01:00
memremap.c	mm, devm_memremap_pages: kill mapping "System RAM" support	2019-01-13 10:01:02 +01:00
module-internal.h
module.c	kernel/module.c: wakeup processes in module_wq on module unload	2019-12-17 20:40:02 +01:00
module_signing.c
notifier.c
nsproxy.c
padata.c	padata: use smp_mb in padata_reorder to avoid orphaned padata jobs	2019-07-31 07:28:39 +02:00
panic.c	panic: ensure preemption is disabled during panic()	2019-10-17 13:43:19 -07:00
params.c	kernel/params.c: improve STANDARD_PARAM_DEF readability	2017-10-03 17:54:26 -07:00
pid.c	pids: make task_tgid_nr_ns() safe	2017-08-21 12:47:31 -07:00
pid_namespace.c	signal/pid_namespace: Fix reboot_pid_ns to use send_sig not force_sig	2019-07-31 07:28:21 +02:00
profile.c
ptrace.c	ptrace: reintroduce usage of subjective credentials in ptrace_has_cap()	2020-01-23 08:20:32 +01:00
range.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
reboot.c
relay.c	relay: check return of create_buf_file() properly	2019-03-13 14:03:20 -07:00
resource.c	resource: fix integer overflow at reallocation	2018-04-24 09:36:22 +02:00
seccomp.c	seccomp: Move speculation migitation control to arch code	2018-05-22 18:54:04 +02:00
signal.c	signal: Always ignore SIGKILL and SIGSTOP sent to the global init	2019-11-20 17:59:52 +01:00
smp.c	cpu/hotplug: Fix "SMT disabled by BIOS" detection for KVM	2019-02-12 19:46:13 +01:00
smpboot.c	watchdog/core, powerpc: Lock cpus across reconfiguration	2017-10-04 10:53:54 +02:00
smpboot.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
softirq.c	Mark HI and TASKLET softirq synchronous	2018-08-15 18:12:47 +02:00
stacktrace.c
stop_machine.c	stop_machine: Atomically queue and wake stopper threads	2018-09-05 09:26:36 +02:00
sys.c	kernel/sys.c: prctl: fix false positive in validate_prctl_map()	2019-06-15 11:54:52 +02:00
sys_ni.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
sysctl.c	kernel: sysctl: make drop_caches write-only	2020-01-04 13:59:57 +01:00
sysctl_binary.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
task_work.c	locking/barriers: Convert users of lockless_dereference() to READ_ONCE()	2017-12-25 14:26:21 +01:00
taskstats.c	taskstats: fix data-race	2020-01-09 10:17:53 +01:00
test_kprobes.c
torture.c
tracepoint.c	tracepoint: Do not warn on ENOMEM	2018-05-09 09:51:50 +02:00
tsacct.c
ucount.c
uid16.c	kernel: make groups_sort calling a responsibility group_info allocators	2017-12-20 10:10:18 +01:00
umh.c	kmod: split out umh code into its own file	2017-09-08 18:26:50 -07:00
up.c	smp: Avoid using two cache lines for struct call_single_data	2017-08-29 15:14:38 +02:00
user-return-notifier.c
user.c
user_namespace.c	userns: move user access out of the mutex	2018-09-09 19:56:00 +02:00
utsname.c
utsname_sysctl.c	sys: don't hold uts_sem while accessing userspace memory	2018-09-09 19:56:00 +02:00
watchdog.c	watchdog: Mark watchdog touch functions as notrace	2018-09-05 09:26:42 +02:00
watchdog_hld.c	watchdog: Mark watchdog touch functions as notrace	2018-09-05 09:26:42 +02:00
workqueue.c	workqueue: Fix missing kfree(rescuer) in destroy_workqueue()	2019-12-17 20:39:59 +01:00
workqueue_internal.h	Merge branch 'for-4.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq	2017-11-06 12:26:49 -08:00