Eric W. Biederman
a371457c19
signal: Allow cifs and drbd to receive their terminating signals ...
[ Upstream commit 33da8e7c814f77310250bb54a9db36a44c5de784 ]
My recent to change to only use force_sig for a synchronous events
wound up breaking signal reception cifs and drbd. I had overlooked
the fact that by default kthreads start out with all signals set to
SIG_IGN. So a change I thought was safe turned out to have made it
impossible for those kernel thread to catch their signals.
Reverting the work on force_sig is a bad idea because what the code
was doing was very much a misuse of force_sig. As the way force_sig
ultimately allowed the signal to happen was to change the signal
handler to SIG_DFL. Which after the first signal will allow userspace
to send signals to these kernel threads. At least for
wake_ack_receiver in drbd that does not appear actively wrong.
So correct this problem by adding allow_kernel_signal that will allow
signals whose siginfo reports they were sent by the kernel through,
but will not allow userspace generated signals, and update cifs and
drbd to call allow_kernel_signal in an appropriate place so that their
thread can receive this signal.
Fixing things this way ensures that userspace won't be able to send
signals and cause problems, that it is clear which signals the
threads are expecting to receive, and it guarantees that nothing
else in the system will be affected.
This change was partly inspired by similar cifs and drbd patches that
added allow_signal.
Reported-by: ronnie sahlberg <ronniesahlberg@gmail.com>
Reported-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Tested-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Cc: Steve French <smfrench@gmail.com>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Fixes: 247bc9470b1e ("cifs: fix rmmod regression in cifs.ko caused by force_sig changes")
Fixes: 72abe3bcf091 ("signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig")
Fixes: fee109901f39 ("signal/drbd: Use send_sig not force_sig")
Fixes: 3cf5d076fb4d ("signal: Remove task parameter from force_sig")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-29 10:24:30 +01:00
bpf: fix bpf_jit_limit knob for PAGE_SIZE >= 64K
2019-08-25 10:51:50 +02:00
config: android: enable CONFIG_SECCOMP
2016-10-11 15:06:32 -07:00
kdb: do a sanity check on the cpu in kdb_per_cpu()
2020-01-29 10:24:24 +01:00
perf/ioctl: Add check for the sample_period value
2020-01-29 10:24:27 +01:00
gcov: support GCC 7.1
2017-09-02 07:07:53 +02:00
genirq: Prevent NULL pointer dereference in resend_irqs()
2019-09-21 07:14:04 +02:00
livepatch/module: make TAINT_LIVEPATCH module-specific
2016-08-26 14:42:08 +02:00
locking/spinlock/debug: Fix various data races
2020-01-12 11:24:20 +01:00
PM / hibernate: memory_bm_find_bit(): Tighten node optimisation
2020-01-12 11:24:11 +01:00
printk: fix integer overflow in setup_log_buf()
2019-11-28 18:28:15 +01:00
rcuperf: Fix cleanup path for invalid perf_type strings
2019-05-31 06:48:30 -07:00
sched/fair: Scale bandwidth quota and period without losing quota/period ratio precision
2019-12-21 10:41:28 +01:00
hrtimer: Annotate lockless access to timer->state
2020-01-04 13:41:08 +01:00
tracing: Have stack tracer compile when MCOUNT_INSN_SIZE is not defined
2020-01-14 20:04:26 +01:00
kernel/acct.c: fix the acct->needcheck check in check_free_space()
2018-01-10 09:29:51 +01:00
kernel/async.c: revert "async: simplify lowest_in_progress()"
2018-02-17 13:21:18 +01:00
audit: return on memory error to avoid null pointer dereference
2018-05-30 07:50:49 +02:00
Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit
2016-07-29 17:54:17 -07:00
audit_get_nd(): don't unlock parent too early
2019-12-21 10:40:48 +01:00
audit: fix a memory leak bug
2019-05-31 06:48:20 -07:00
audit: print empty EXECVE args
2019-11-28 18:28:55 +01:00
kbuild: fix kernel/bounds.c 'W=1' warning
2018-11-13 11:16:57 -08:00
ptrace: Capture the ptracer's creds not PT_PTRACE_CAP
2017-01-06 10:40:13 +01:00
cgroup: Fix deadlock in cpu hotplug path
2018-10-13 09:18:56 +02:00
cgroup: pids: use atomic64_t for pids->limit
2019-12-21 10:42:02 +01:00
cpu/SMT: State SMT is disabled even with nosmt and without "=force"
2019-11-25 09:53:32 +01:00
sched/cpuset/pm: Fix cpuset vs. suspend-resume bugs
2017-10-12 11:51:25 +02:00
memcg: account security cred as well to kmemcg
2020-01-12 11:24:13 +01:00
kernel/elfcore.c: include proper prototypes
2019-10-17 13:42:13 -07:00
kernel/exit.c: release ptraced tasks before zap_pid_ns_processes
2019-02-06 17:33:29 +01:00
kernel/extable.c: mark core_kernel_text notrace
2017-07-21 07:42:21 +02:00
kernel/sysctl.c: do not override max_threads provided by userspace
2019-10-17 13:42:44 -07:00
freezer, oom: check TIF_MEMDIE on the correct task
2016-07-28 16:07:41 -07:00
futex: Ensure that futex address is aligned in handle_futex_death()
2019-03-27 14:13:03 +09:00
kernel: make groups_sort calling a responsibility group_info allocators
2018-01-10 09:29:52 +01:00
kernel: hung_task.c: disable on suspend
2019-04-20 09:07:52 +02:00
jump_label: Invoke jump_label_test() via early_initcall()
2017-12-14 09:28:24 +01:00
kcov: ensure irq code sees a valid area
2018-08-03 07:55:12 +02:00
kexec: allow architectures to override boot mapping
2016-08-02 19:35:27 -04:00
objtool, x86: Add several functions and files to the objtool whitelist
2018-06-05 10:28:57 +02:00
kexec: fix double-free when failing to relocate the purgatory
2016-09-01 17:52:01 -07:00
kprobes: Don't call BUG_ON() if there is a kprobe in use on free list
2019-11-25 09:52:15 +01:00
kexec: add a kexec_crash_loaded() function
2016-08-02 19:35:30 -04:00
kthread, tracing: Don't expose half-written comm when creating kthreads
2018-08-03 07:55:12 +02:00
x86/uaccess, kcov: Disable stack protector
2019-06-22 08:17:19 +02:00
Fix: Disable sys_membarrier when nohz_full is enabled
2017-03-12 06:41:45 +01:00
mm, devm_memremap_pages: kill mapping "System RAM" support
2019-01-13 10:03:51 +01:00
kernel/module.c: wakeup processes in module_wq on module unload
2019-12-21 10:42:21 +01:00
padata: use smp_mb in padata_reorder to avoid orphaned padata jobs
2019-08-04 09:33:28 +02:00
panic: ensure preemption is disabled during panic()
2019-10-17 13:42:25 -07:00
pidns: disable pid allocation if pid_ns_prepare_proc() is failed in alloc_pid()
2018-04-13 19:47:53 +02:00
signal/pid_namespace: Fix reboot_pid_ns to use send_sig not force_sig
2019-08-04 09:33:16 +02:00
profile: Convert to hotplug state machine
2016-07-15 10:41:42 +02:00
ptrace: Fix ->ptracer_cred handling for PTRACE_TRACEME
2019-07-10 09:55:45 +02:00
kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE
2018-05-30 07:50:29 +02:00
resource: fix integer overflow at reallocation
2018-04-24 09:34:09 +02:00
seccomp: Move speculation migitation control to arch code
2018-05-22 16:58:02 +02:00
signal: Allow cifs and drbd to receive their terminating signals
2020-01-29 10:24:30 +01:00
cpu/hotplug: Fix SMT supported evaluation
2018-08-15 18:14:53 +02:00
kthread/smpboot: do not park in kthread_create_on_cpu()
2016-10-11 15:06:33 -07:00
Mark HI and TASKLET softirq synchronous
2018-08-15 18:14:42 +02:00
stacktrace, lockdep: Fix address, newline ugliness
2017-02-14 15:25:42 -08:00
stop_machine: Use raw spinlocks
2018-08-03 07:55:24 +02:00
kernel/sys.c: prctl: fix false positive in validate_prctl_map()
2019-06-22 08:17:13 +02:00
x86/pkeys: Fix pkeys build breakage for some non-x86 arches
2016-09-13 14:41:36 +02:00
kernel: sysctl: make drop_caches write-only
2020-01-04 13:41:04 +01:00
kernel/sysctl_binary.c: use generic UUID library
2016-05-20 17:58:30 -07:00
task_work: use READ_ONCE/lockless_dereference, avoid pi_lock if !task_works
2016-08-02 19:35:02 -04:00
taskstats: fix data-race
2020-01-12 11:24:12 +01:00
torture: Convert torture_shutdown() to hrtimer
2016-08-22 10:01:49 -07:00
tracepoint: Do not warn on ENOMEM
2018-05-09 09:50:20 +02:00
kernel/ucount.c: mark user_header with kmemleak_ignore()
2017-06-17 06:41:51 +02:00
kernel: make groups_sort calling a responsibility group_info allocators
2018-01-10 09:29:52 +01:00
smp: Add function to execute a function synchronously on a CPU
2016-09-05 13:52:39 +02:00
userns: move user access out of the mutex
2018-09-09 20:01:24 +02:00
Merge branch 'nsfs-ioctls' into HEAD
2016-09-22 20:00:36 -05:00
sys: don't hold uts_sem while accessing userspace memory
2018-09-09 20:01:24 +02:00
kernel/watchdog: prevent false hardlockup on overloaded system
2017-06-17 06:41:57 +02:00
kernel/watchdog: prevent false hardlockup on overloaded system
2017-06-17 06:41:57 +02:00
workqueue: Fix missing kfree(rescuer) in destroy_workqueue()
2019-12-21 10:42:19 +01:00
workqueue: Fix NULL pointer dereference
2017-11-15 15:53:17 +01:00
a371457c19