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Kuniyuki Iwashima b474ff1b20 kprobes: don't call disarm_kprobe() for disabled kprobes 
commit 9c80e79906b4ca440d09e7f116609262bb747909 upstream.

The assumption in __disable_kprobe() is wrong, and it could try to disarm
an already disarmed kprobe and fire the WARN_ONCE() below. [0]  We can
easily reproduce this issue.

1. Write 0 to /sys/kernel/debug/kprobes/enabled.

  # echo 0 > /sys/kernel/debug/kprobes/enabled

2. Run execsnoop.  At this time, one kprobe is disabled.

  # /usr/share/bcc/tools/execsnoop &
  [1] 2460
  PCOMM            PID    PPID   RET ARGS

  # cat /sys/kernel/debug/kprobes/list
  ffffffff91345650  r  __x64_sys_execve+0x0    [FTRACE]
  ffffffff91345650  k  __x64_sys_execve+0x0    [DISABLED][FTRACE]

3. Write 1 to /sys/kernel/debug/kprobes/enabled, which changes
   kprobes_all_disarmed to false but does not arm the disabled kprobe.

  # echo 1 > /sys/kernel/debug/kprobes/enabled

  # cat /sys/kernel/debug/kprobes/list
  ffffffff91345650  r  __x64_sys_execve+0x0    [FTRACE]
  ffffffff91345650  k  __x64_sys_execve+0x0    [DISABLED][FTRACE]

4. Kill execsnoop, when __disable_kprobe() calls disarm_kprobe() for the
   disabled kprobe and hits the WARN_ONCE() in __disarm_kprobe_ftrace().

  # fg
  /usr/share/bcc/tools/execsnoop
  ^C

Actually, WARN_ONCE() is fired twice, and __unregister_kprobe_top() misses
some cleanups and leaves the aggregated kprobe in the hash table.  Then,
__unregister_trace_kprobe() initialises tk->rp.kp.list and creates an
infinite loop like this.

  aggregated kprobe.list -> kprobe.list -.
                                     ^    |
                                     '.__.'

In this situation, these commands fall into the infinite loop and result
in RCU stall or soft lockup.

  cat /sys/kernel/debug/kprobes/list : show_kprobe_addr() enters into the
                                       infinite loop with RCU.

  /usr/share/bcc/tools/execsnoop : warn_kprobe_rereg() holds kprobe_mutex,
                                   and __get_valid_kprobe() is stuck in
				   the loop.

To avoid the issue, make sure we don't call disarm_kprobe() for disabled
kprobes.

[0]
Failed to disarm kprobe-ftrace at __x64_sys_execve+0x0/0x40 (error -2)
WARNING: CPU: 6 PID: 2460 at kernel/kprobes.c:1130 __disarm_kprobe_ftrace.isra.19 (kernel/kprobes.c:1129)
Modules linked in: ena
CPU: 6 PID: 2460 Comm: execsnoop Not tainted 5.19.0+ #28
Hardware name: Amazon EC2 c5.2xlarge/, BIOS 1.0 10/16/2017
RIP: 0010:__disarm_kprobe_ftrace.isra.19 (kernel/kprobes.c:1129)
Code: 24 8b 02 eb c1 80 3d c4 83 f2 01 00 75 d4 48 8b 75 00 89 c2 48 c7 c7 90 fa 0f 92 89 04 24 c6 05 ab 83 01 e8 e4 94 f0 ff <0f> 0b 8b 04 24 eb b1 89 c6 48 c7 c7 60 fa 0f 92 89 04 24 e8 cc 94
RSP: 0018:ffff9e6ec154bd98 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffffff930f7b00 RCX: 0000000000000001
RDX: 0000000080000001 RSI: ffffffff921461c5 RDI: 00000000ffffffff
RBP: ffff89c504286da8 R08: 0000000000000000 R09: c0000000fffeffff
R10: 0000000000000000 R11: ffff9e6ec154bc28 R12: ffff89c502394e40
R13: ffff89c502394c00 R14: ffff9e6ec154bc00 R15: 0000000000000000
FS:  00007fe800398740(0000) GS:ffff89c812d80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00057f010 CR3: 0000000103b54006 CR4: 00000000007706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
 __disable_kprobe (kernel/kprobes.c:1716)
 disable_kprobe (kernel/kprobes.c:2392)
 __disable_trace_kprobe (kernel/trace/trace_kprobe.c:340)
 disable_trace_kprobe (kernel/trace/trace_kprobe.c:429)
 perf_trace_event_unreg.isra.2 (./include/linux/tracepoint.h:93 kernel/trace/trace_event_perf.c:168)
 perf_kprobe_destroy (kernel/trace/trace_event_perf.c:295)
 _free_event (kernel/events/core.c:4971)
 perf_event_release_kernel (kernel/events/core.c:5176)
 perf_release (kernel/events/core.c:5186)
 __fput (fs/file_table.c:321)
 task_work_run (./include/linux/sched.h:2056 (discriminator 1) kernel/task_work.c:179 (discriminator 1))
 exit_to_user_mode_prepare (./include/linux/resume_user_mode.h:49 kernel/entry/common.c:169 kernel/entry/common.c:201)
 syscall_exit_to_user_mode (./arch/x86/include/asm/jump_label.h:55 ./arch/x86/include/asm/nospec-branch.h:384 ./arch/x86/include/asm/entry-common.h:94 kernel/entry/common.c:133 kernel/entry/common.c:296)
 do_syscall_64 (arch/x86/entry/common.c:87)
 entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
RIP: 0033:0x7fe7ff210654
Code: 15 79 89 20 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb be 0f 1f 00 8b 05 9a cd 20 00 48 63 ff 85 c0 75 11 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 3a f3 c3 48 83 ec 18 48 89 7c 24 08 e8 34 fc
RSP: 002b:00007ffdbd1d3538 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000008 RCX: 00007fe7ff210654
RDX: 0000000000000000 RSI: 0000000000002401 RDI: 0000000000000008
RBP: 0000000000000000 R08: 94ae31d6fda838a4 R0900007fe8001c9d30
R10: 00007ffdbd1d34b0 R11: 0000000000000246 R12: 00007ffdbd1d3600
R13: 0000000000000000 R14: fffffffffffffffc R15: 00007ffdbd1d3560
</TASK>

Link: https://lkml.kernel.org/r/20220813020509.90805-1-kuniyu@amazon.com
Fixes: 69d54b916d83 ("kprobes: makes kprobes/enabled works correctly for optimized kprobes.")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reported-by: Ayushman Dutta <ayudutta@amazon.com>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Kuniyuki Iwashima <kuniyu@amazon.com>
Cc: Kuniyuki Iwashima <kuni1840@gmail.com>
Cc: Ayushman Dutta <ayudutta@amazon.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:27:47 +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: Use separate src/dst nodes when preloading css_sets for migration
2022-07-21 20:59:17 +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
ftrace: Fix NULL pointer dereference in is_ftrace_trampoline when ftrace is dead
2022-09-05 10:27:45 +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_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
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
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
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
bounds.c
…
capability.c
…
compat.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
2019-06-19 17:09:55 +02:00
configs.c
kernel/configs: Replace GPL boilerplate code with SPDX identifier
2019-07-30 18:34:15 +02:00
context_tracking.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
cpu_pm.c
kernel/cpu_pm: Fix uninitted local in cpu_pm
2020-06-22 09:31:22 +02:00
cpu.c
random: clear fast pool, crng, and batches in cpuhp bring up
2022-06-22 14:11:12 +02:00
crash_core.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230
2019-06-19 17:09:06 +02:00
crash_dump.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
cred.c
keys: Fix request_key() cache
2020-01-17 19:48:42 +01:00
delayacct.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 25
2019-05-21 11:52:39 +02:00
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
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
iomem.c
mm/nvdimm: add is_ioremap_addr and use that to check ioremap address
2019-07-12 11:05:40 -07:00
irq_work.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
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
treewide: Add SPDX license identifier - Makefile/Kconfig
2019-05-21 10:50:46 +02:00
Kconfig.hz
treewide: Add SPDX license identifier - Makefile/Kconfig
2019-05-21 10:50:46 +02:00
Kconfig.locks
treewide: Add SPDX license identifier - Makefile/Kconfig
2019-05-21 10:50:46 +02:00
Kconfig.preempt
sched/rt, Kconfig: Unbreak def/oldconfig with CONFIG_PREEMPT=y
2019-07-22 18:05:11 +02:00
kcov.c
…
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
…
kexec.c
kexec_load: Disable at runtime if the kernel is locked down
2019-08-19 21:54:15 -07:00
kheaders.c
kheaders: Move from proc to sysfs
2019-05-24 20:16:01 +02:00
kmod.c
kmod: make request_module() return an error when autoloading is disabled
2020-04-17 10:50:22 +02:00
kprobes.c
kprobes: don't call disarm_kprobe() for disabled kprobes
2022-09-05 10:27:47 +02:00
ksysfs.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 170
2019-05-30 11:26:39 -07:00
kthread.c
kthread: Fix PF_KTHREAD vs to_kthread() race
2021-09-12 08:56:39 +02:00
latencytop.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
Makefile
kbuild: update config_data.gz only when the content of .config is changed
2021-05-11 14:04:16 +02:00
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
module-internal.h
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36
2019-05-24 17:27:11 +02:00
module.c
module/ftrace: handle patchable-function-entry
2022-02-23 11:59:56 +01:00
notifier.c
kernel/notifier.c: intercept duplicate registrations to avoid infinite loops
2020-10-01 13:17:23 +02:00
nsproxy.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
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_namespace.c
memcg: enable accounting for pids in nested pid namespaces
2021-09-22 12:26:37 +02:00
pid.c
kernel/pid.c: convert struct pid count to refcount_t
2019-07-16 19:23:24 -07:00
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
signal: Remove task parameter from force_sig
2019-05-27 09:36:28 -05:00
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
Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-07-08 11:01:13 -07:00
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_ni.c
kernel/sys_ni: add compat entry for fadvise64_64
2022-09-05 10:27:38 +02:00
sys.c
prctl: allow to setup brk for et_dyn executables
2021-09-26 14:07:08 +02:00
sysctl_binary.c
…
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
task_work.c
…
taskstats.c
taskstats: fix data-race
2020-01-09 10:19:54 +01:00
test_kprobes.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 25
2019-05-21 11:52:39 +02:00
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_namespace.c
Keyrings namespacing
2019-07-08 19:36:47 -07:00
user-return-notifier.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
user.c
Keyrings namespacing
2019-07-08 19:36:47 -07:00
utsname_sysctl.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
utsname.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
watchdog_hld.c
…
watchdog.c
watchdog: export lockup_detector_reconfigure
2022-08-25 11:18:37 +02:00
workqueue_internal.h
…
workqueue.c
workqueue: Fix unbind_workers() VS wq_worker_running() race
2022-01-16 09:15:38 +01:00