Repository files (latest commit first)

Filename	Latest commit message	Latest commit date
Tetsuo Handa 04aa8187eb workqueue: don't skip lockdep work dependency in cancel_work_sync() ... [ Upstream commit c0feea594e058223973db94c1c32a830c9807c86 ] Like Hillf Danton mentioned syzbot should have been able to catch cancel_work_sync() in work context by checking lockdep_map in __flush_work() for both flush and cancel. in [1], being unable to report an obvious deadlock scenario shown below is broken. From locking dependency perspective, sync version of cancel request should behave as if flush request, for it waits for completion of work if that work has already started execution. ---------- #include <linux/module.h> #include <linux/sched.h> static DEFINE_MUTEX(mutex); static void work_fn(struct work_struct *work) { schedule_timeout_uninterruptible(HZ / 5); mutex_lock(&mutex); mutex_unlock(&mutex); } static DECLARE_WORK(work, work_fn); static int __init test_init(void) { schedule_work(&work); schedule_timeout_uninterruptible(HZ / 10); mutex_lock(&mutex); cancel_work_sync(&work); mutex_unlock(&mutex); return -EINVAL; } module_init(test_init); MODULE_LICENSE("GPL"); ---------- The check this patch restores was added by commit 0976dfc1d0 ("workqueue: Catch more locking problems with flush_work()"). Then, lockdep's crossrelease feature was added by commit b09be676e0 ("locking/lockdep: Implement the 'crossrelease' feature"). As a result, this check was once removed by commit fd1a5b04df ("workqueue: Remove now redundant lock acquisitions wrt. workqueue flushes"). But lockdep's crossrelease feature was removed by commit e966eaeeb6 ("locking/lockdep: Remove the cross-release locking checks"). At this point, this check should have been restored. Then, commit d6e89786be ("workqueue: skip lockdep wq dependency in cancel_work_sync()") introduced a boolean flag in order to distinguish flush_work() and cancel_work_sync(), for checking "struct workqueue_struct" dependency when called from cancel_work_sync() was causing false positives. Then, commit 87915adc3f ("workqueue: re-add lockdep dependencies for flushing") tried to restore "struct work_struct" dependency check, but by error checked this boolean flag. Like an example shown above indicates, "struct work_struct" dependency needs to be checked for both flush_work() and cancel_work_sync(). Link: https://lkml.kernel.org/r/20220504044800.4966-1-hdanton@sina.com [1] Reported-by: Hillf Danton <hdanton@sina.com> Suggested-by: Lai Jiangshan <jiangshanlai@gmail.com> Fixes: 87915adc3f ("workqueue: re-add lockdep dependencies for flushing") Cc: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2022-09-28 11:04:09 +02:00
..
bpf	bpf: Verifer, adjust_scalar_min_max_vals to always call update_reg_bounds()	2022-08-11 12:57:51 +02:00
cgroup	cgroup: Add missing cpus_read_lock() to cgroup_attach_task_all()	2022-09-28 11:03:59 +02:00
configs
debug	lockdown: also lock down previous kgdb use	2022-06-06 08:33:48 +02:00
dma	dma-debug: make things less spammy under memory pressure	2022-06-22 14:11:19 +02:00
events	perf/core: Fix data race between perf_event_set_output() and perf_mmap_close()	2022-07-29 17:14:10 +02:00
gcov	gcov: re-fix clang-11+ support	2021-04-14 08:24:10 +02:00
irq	genirq: Don't return error on missing optional irq_request_resources()	2022-08-25 11:17:29 +02:00
livepatch	livepatch: Nullify obj->mod in klp_module_coming()'s error path	2019-08-19 13:03:37 +02:00
locking	locking/lockdep: Avoid RCU-induced noinstr fail	2021-11-17 09:48:28 +01:00
power	PM: hibernate: defer device probing when resuming from hibernation	2022-08-25 11:17:32 +02:00
printk	printk: fix return value of printk.devkmsg __setup handler	2022-04-15 14:18:08 +02:00
rcu	rcu: Don't deboost before reporting expedited quiescent state	2022-03-28 08:46:48 +02:00
sched	sched/deadline: Fix priority inheritance with multiple scheduling classes	2022-09-05 10:27:39 +02:00
time	timekeeping: contribute wall clock to rng on time change	2022-08-25 11:18:15 +02:00
trace	tracing: hold caller_addr to hardirq_{enable,disable}_ip	2022-09-28 11:03:57 +02:00
.gitignore	kbuild: update config_data.gz only when the content of .config is changed	2021-05-11 14:04:16 +02:00
acct.c
async.c	Revert "module, async: async_synchronize_full() on module init iff async is used"	2022-02-23 11:59:56 +01:00
audit.c	audit: improve audit queue handling when "audit=1" on cmdline	2022-02-08 18:24:26 +01:00
audit.h	audit: log AUDIT_TIME_* records only from rules	2022-04-15 14:18:04 +02:00
audit_fsnotify.c	audit: fix potential double free on error path from fsnotify_add_inode_mark	2022-09-05 10:27:38 +02:00
audit_tree.c	audit: move put_tree() to avoid trim_trees refcount underflow and UAF	2021-09-03 10:08:16 +02:00
audit_watch.c	audit: CONFIG_CHANGE don't log internal bookkeeping as an event	2020-10-01 13:17:32 +02:00
auditfilter.c	audit: fix a net reference leak in audit_list_rules_send()	2020-06-22 09:30:59 +02:00
auditsc.c	audit: log AUDIT_TIME_* records only from rules	2022-04-15 14:18:04 +02:00
backtracetest.c
bounds.c
capability.c
compat.c
configs.c	kernel/configs: Replace GPL boilerplate code with SPDX identifier	2019-07-30 18:34:15 +02:00
context_tracking.c
cpu.c	random: clear fast pool, crng, and batches in cpuhp bring up	2022-06-22 14:11:12 +02:00
cpu_pm.c	kernel/cpu_pm: Fix uninitted local in cpu_pm	2020-06-22 09:31:22 +02:00
crash_core.c
crash_dump.c
cred.c	keys: Fix request_key() cache	2020-01-17 19:48:42 +01:00
delayacct.c
dma.c
exec_domain.c
exit.c	don't dump the threads that had been already exiting when zapped.	2020-11-18 19:20:31 +01:00
extable.c	extable: Add function to search only kernel exception table	2019-08-21 22:23:48 +10:00
fail_function.c	fail_function: Remove a redundant mutex unlock	2020-11-24 13:29:18 +01:00
fork.c	copy_process(): Move fd_install() out of sighand->siglock critical section	2022-02-23 12:00:00 +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	mm, futex: fix shared futex pgoff on shmem huge page	2021-06-30 08:47:55 -04:00
gen_kheaders.sh	kbuild: add variables for compression tools	2020-09-03 11:27:10 +02:00
groups.c
hung_task.c
iomem.c
irq_work.c
jump_label.c	jump_label: Don't warn on __exit jump entries	2019-08-29 15:10:10 +01:00
kallsyms.c	kallsyms: Refactor kallsyms_show_value() to take cred	2020-07-16 08:16:44 +02:00
kcmp.c	exec: Transform exec_update_mutex into a rw_semaphore	2021-01-09 13:44:55 +01:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt	sched/rt, Kconfig: Unbreak def/oldconfig with CONFIG_PREEMPT=y	2019-07-22 18:05:11 +02:00
kcov.c
kexec.c	kexec_load: Disable at runtime if the kernel is locked down	2019-08-19 21:54:15 -07:00
kexec_core.c	kernel: kexec: remove the lock operation of system_transition_mutex	2021-02-03 23:25:56 +01:00
kexec_elf.c	kexec_elf: support 32 bit ELF files	2019-09-06 23:58:44 +02:00
kexec_file.c	kexec_file: drop weak attribute from arch_kexec_apply_relocations[_add]	2022-07-02 16:28:50 +02:00
kexec_internal.h
kheaders.c
kmod.c	kmod: make request_module() return an error when autoloading is disabled	2020-04-17 10:50:22 +02:00
kprobes.c	kprobes: Prohibit probes in gate area	2022-09-15 12:04:54 +02:00
ksysfs.c
kthread.c	kthread: Fix PF_KTHREAD vs to_kthread() race	2021-09-12 08:56:39 +02:00
latencytop.c
Makefile	kbuild: update config_data.gz only when the content of .config is changed	2021-05-11 14:04:16 +02:00
module-internal.h
module.c	module/ftrace: handle patchable-function-entry	2022-02-23 11:59:56 +01:00
module_signature.c	module: harden ELF info handling	2021-04-07 14:47:38 +02:00
module_signing.c	module: harden ELF info handling	2021-04-07 14:47:38 +02:00
notifier.c	kernel/notifier.c: intercept duplicate registrations to avoid infinite loops	2020-10-01 13:17:23 +02:00
nsproxy.c
padata.c	padata: add separate cpuhp node for CPUHP_PADATA_DEAD	2020-06-17 16:40:22 +02:00
panic.c	panic: ensure preemption is disabled during panic()	2019-10-07 15:47:19 -07:00
params.c	lockdown: Lock down module params that specify hardware parameters (eg. ioport)	2019-08-19 21:54:16 -07:00
pid.c
pid_namespace.c	memcg: enable accounting for pids in nested pid namespaces	2021-09-22 12:26:37 +02:00
profile.c	profiling: fix shift too large makes kernel panic	2022-08-25 11:18:02 +02:00
ptrace.c	ptrace: Reimplement PTRACE_KILL by always sending SIGKILL	2022-06-14 18:11:24 +02:00
range.c
reboot.c	reboot: fix overflow parsing reboot cpu number	2020-11-18 19:20:30 +01:00
relay.c	kernel/relay.c: fix memleak on destroy relay channel	2020-08-26 10:40:51 +02:00
resource.c	/dev/mem: Revoke mappings when a driver claims the region	2020-06-24 17:50:35 +02:00
rseq.c
seccomp.c	seccomp: Invalidate seccomp mode to catch death failures	2022-02-16 12:52:53 +01:00
signal.c	signal handling: don't use BUG_ON() for debugging	2022-07-21 20:59:27 +02:00
smp.c	smp: Fix offline cpu check in flush_smp_call_function_queue()	2022-04-20 09:19:39 +02:00
smpboot.c	kthread: Extract KTHREAD_IS_PER_CPU	2021-02-07 15:35:49 +01:00
smpboot.h
softirq.c
stackleak.c
stacktrace.c	stacktrace: Don't skip first entry on noncurrent tasks	2019-11-04 21:19:25 +01:00
stop_machine.c	stop_machine: Avoid potential race behaviour	2019-10-17 12:47:12 +02:00
sys.c	prctl: allow to setup brk for et_dyn executables	2021-09-26 14:07:08 +02:00
sys_ni.c	kernel/sys_ni: add compat entry for fadvise64_64	2022-09-05 10:27:38 +02:00
sysctl-test.c	kernel/sysctl-test: Add null pointer test for sysctl.c:proc_dointvec()	2020-10-01 13:17:10 +02:00
sysctl.c	mm: sysctl: fix missing numa_stat when !CONFIG_HUGETLB_PAGE	2022-07-21 20:59:24 +02:00
sysctl_binary.c
task_work.c
taskstats.c	taskstats: fix data-race	2020-01-09 10:19:54 +01:00
test_kprobes.c
torture.c	torture: Remove exporting of internal functions	2019-08-01 14:30:22 -07:00
tracepoint.c	tracepoint: Add tracepoint_probe_register_may_exist() for BPF tracing	2021-07-14 16:53:08 +02:00
tsacct.c	taskstats: Cleanup the use of task->exit_code	2022-02-23 11:59:57 +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	usermodehelper: reset umask to default before executing user process	2020-10-14 10:32:58 +02:00
up.c	smp: Fix smp_call_function_single_async prototype	2021-05-14 09:44:33 +02:00
user-return-notifier.c
user.c
user_namespace.c
utsname.c
utsname_sysctl.c
watchdog.c	watchdog: export lockup_detector_reconfigure	2022-08-25 11:18:37 +02:00
watchdog_hld.c
workqueue.c	workqueue: don't skip lockdep work dependency in cancel_work_sync()	2022-09-28 11:04:09 +02:00
workqueue_internal.h