linux/kernel/time
Eric Dumazet 90c018942c timer: Use hlist_unhashed_lockless() in timer_pending()
The timer_pending() function is mostly used in lockless contexts, so
Without proper annotations, KCSAN might detect a data-race [1].

Using hlist_unhashed_lockless() instead of hand-coding it seems
appropriate (as suggested by Paul E. McKenney).

[1]

BUG: KCSAN: data-race in del_timer / detach_if_pending

write to 0xffff88808697d870 of 8 bytes by task 10 on cpu 0:
 __hlist_del include/linux/list.h:764 [inline]
 detach_timer kernel/time/timer.c:815 [inline]
 detach_if_pending+0xcd/0x2d0 kernel/time/timer.c:832
 try_to_del_timer_sync+0x60/0xb0 kernel/time/timer.c:1226
 del_timer_sync+0x6b/0xa0 kernel/time/timer.c:1365
 schedule_timeout+0x2d2/0x6e0 kernel/time/timer.c:1896
 rcu_gp_fqs_loop+0x37c/0x580 kernel/rcu/tree.c:1639
 rcu_gp_kthread+0x143/0x230 kernel/rcu/tree.c:1799
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

read to 0xffff88808697d870 of 8 bytes by task 12060 on cpu 1:
 del_timer+0x3b/0xb0 kernel/time/timer.c:1198
 sk_stop_timer+0x25/0x60 net/core/sock.c:2845
 inet_csk_clear_xmit_timers+0x69/0xa0 net/ipv4/inet_connection_sock.c:523
 tcp_clear_xmit_timers include/net/tcp.h:606 [inline]
 tcp_v4_destroy_sock+0xa3/0x3f0 net/ipv4/tcp_ipv4.c:2096
 inet_csk_destroy_sock+0xf4/0x250 net/ipv4/inet_connection_sock.c:836
 tcp_close+0x6f3/0x970 net/ipv4/tcp.c:2497
 inet_release+0x86/0x100 net/ipv4/af_inet.c:427
 __sock_release+0x85/0x160 net/socket.c:590
 sock_close+0x24/0x30 net/socket.c:1268
 __fput+0x1e1/0x520 fs/file_table.c:280
 ____fput+0x1f/0x30 fs/file_table.c:313
 task_work_run+0xf6/0x130 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:163

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 12060 Comm: syz-executor.5 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine,

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
[ paulmck: Pulled in Eric's later amendments. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-02-20 15:58:22 -08:00
..
alarmtimer.c alarmtimer: Make alarmtimer_get_rtcdev() a stub when CONFIG_RTC_CLASS=n 2020-01-24 21:03:53 +01:00
clockevents.c tick: Remove outgoing CPU from broadcast masks 2019-03-23 18:26:43 +01:00
clocksource.c clocksource: Prevent double add_timer_on() for watchdog_timer 2020-02-01 11:07:56 +01:00
hrtimer.c hrtimer: Add missing sparse annotation for __run_timer() 2020-01-22 15:50:11 +01:00
itimer.c y2038: rename itimerval to __kernel_old_itimerval 2019-12-18 18:07:33 +01:00
jiffies.c Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-05-06 14:50:46 -07:00
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile ns: Introduce Time Namespace 2020-01-14 12:20:48 +01:00
namespace.c fs/proc: Introduce /proc/pid/timens_offsets 2020-01-14 12:20:59 +01:00
ntp.c ntp/y2038: Remove incorrect time_t truncation 2019-11-12 08:13:44 +01:00
ntp_internal.h ntp: Audit NTP parameters adjustment 2019-04-15 18:14:01 -04:00
posix-clock.c posix-clocks: Rename the clock_get() callback to clock_get_timespec() 2020-01-14 12:20:49 +01:00
posix-cpu-timers.c posix-clocks: Rename the clock_get() callback to clock_get_timespec() 2020-01-14 12:20:49 +01:00
posix-stubs.c posix-timers: Make clock_nanosleep() time namespace aware 2020-01-14 12:20:55 +01:00
posix-timers.c posix-timers: Make clock_nanosleep() time namespace aware 2020-01-14 12:20:55 +01:00
posix-timers.h posix-clocks: Introduce clock_get_ktime() callback 2020-01-14 12:20:51 +01:00
sched_clock.c time/sched_clock: Disable interrupts in sched_clock_register() 2020-01-09 18:50:18 +01:00
test_udelay.c time/debug: Remove license boilerplate 2018-11-23 11:51:21 +01:00
tick-broadcast-hrtimer.c tick: broadcast-hrtimer: Fix a race in bc_set_next 2019-09-27 14:45:55 +02:00
tick-broadcast.c tick: Fix typos in comments 2019-04-19 19:17:04 +02:00
tick-common.c tick/common: Touch watchdog in tick_unfreeze() on all CPUs 2020-01-15 21:29:45 +01:00
tick-internal.h tick: Remove outgoing CPU from broadcast masks 2019-03-23 18:26:43 +01:00
tick-oneshot.c hrtimers/tick/clockevents: Remove sloppy license references 2018-11-23 11:51:21 +01:00
tick-sched.c tick/sched: Annotate lockless access to last_jiffies_update 2020-01-15 10:54:12 +01:00
tick-sched.h tick/sched: Update tick_sched struct documentation 2019-03-24 20:29:32 +01:00
time.c y2038: remove obsolete jiffies conversion functions 2019-12-18 18:07:33 +01:00
timeconst.bc time: Add SPDX license identifiers 2018-11-23 11:51:20 +01:00
timeconv.c time: Add SPDX license identifiers 2018-11-23 11:51:20 +01:00
timecounter.c time: Remove license boilerplate 2018-11-23 11:51:21 +01:00
timekeeping.c timekeeping/vsyscall: Prevent math overflow in BOOTTIME update 2019-08-23 02:12:11 +02:00
timekeeping.h timers/sched_clock: Prevent generic sched_clock wrap caused by tick_freeze() 2019-04-18 14:34:53 +02:00
timekeeping_debug.c timekeeping/debug: No need to check return value of debugfs_create functions 2019-01-29 20:08:41 +01:00
timekeeping_internal.h timekeeping/ntp: Constify some function arguments 2018-07-19 17:08:05 -07:00
timer.c timer: Use hlist_unhashed_lockless() in timer_pending() 2020-02-20 15:58:22 -08:00
timer_list.c timer_list: Guard procfs specific code 2019-06-23 00:08:52 +02:00
vsyscall.c lib/vdso: Update coarse timekeeper unconditionally 2020-01-17 15:53:50 +01:00