linux-brain/kernel
Liangyan d63f00ec90 tracing: Correct the length check which causes memory corruption
commit 3e08a9f9760f4a70d633c328a76408e62d6f80a3 upstream.

We've suffered from severe kernel crashes due to memory corruption on
our production environment, like,

Call Trace:
[1640542.554277] general protection fault: 0000 [#1] SMP PTI
[1640542.554856] CPU: 17 PID: 26996 Comm: python Kdump: loaded Tainted:G
[1640542.556629] RIP: 0010:kmem_cache_alloc+0x90/0x190
[1640542.559074] RSP: 0018:ffffb16faa597df8 EFLAGS: 00010286
[1640542.559587] RAX: 0000000000000000 RBX: 0000000000400200 RCX:
0000000006e931bf
[1640542.560323] RDX: 0000000006e931be RSI: 0000000000400200 RDI:
ffff9a45ff004300
[1640542.560996] RBP: 0000000000400200 R08: 0000000000023420 R09:
0000000000000000
[1640542.561670] R10: 0000000000000000 R11: 0000000000000000 R12:
ffffffff9a20608d
[1640542.562366] R13: ffff9a45ff004300 R14: ffff9a45ff004300 R15:
696c662f65636976
[1640542.563128] FS:  00007f45d7c6f740(0000) GS:ffff9a45ff840000(0000)
knlGS:0000000000000000
[1640542.563937] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[1640542.564557] CR2: 00007f45d71311a0 CR3: 000000189d63e004 CR4:
00000000003606e0
[1640542.565279] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[1640542.566069] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[1640542.566742] Call Trace:
[1640542.567009]  anon_vma_clone+0x5d/0x170
[1640542.567417]  __split_vma+0x91/0x1a0
[1640542.567777]  do_munmap+0x2c6/0x320
[1640542.568128]  vm_munmap+0x54/0x70
[1640542.569990]  __x64_sys_munmap+0x22/0x30
[1640542.572005]  do_syscall_64+0x5b/0x1b0
[1640542.573724]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[1640542.575642] RIP: 0033:0x7f45d6e61e27

James Wang has reproduced it stably on the latest 4.19 LTS.
After some debugging, we finally proved that it's due to ftrace
buffer out-of-bound access using a debug tool as follows:
[   86.775200] BUG: Out-of-bounds write at addr 0xffff88aefe8b7000
[   86.780806]  no_context+0xdf/0x3c0
[   86.784327]  __do_page_fault+0x252/0x470
[   86.788367]  do_page_fault+0x32/0x140
[   86.792145]  page_fault+0x1e/0x30
[   86.795576]  strncpy_from_unsafe+0x66/0xb0
[   86.799789]  fetch_memory_string+0x25/0x40
[   86.804002]  fetch_deref_string+0x51/0x60
[   86.808134]  kprobe_trace_func+0x32d/0x3a0
[   86.812347]  kprobe_dispatcher+0x45/0x50
[   86.816385]  kprobe_ftrace_handler+0x90/0xf0
[   86.820779]  ftrace_ops_assist_func+0xa1/0x140
[   86.825340]  0xffffffffc00750bf
[   86.828603]  do_sys_open+0x5/0x1f0
[   86.832124]  do_syscall_64+0x5b/0x1b0
[   86.835900]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

commit b220c049d519 ("tracing: Check length before giving out
the filter buffer") adds length check to protect trace data
overflow introduced in 0fc1b09ff1, seems that this fix can't prevent
overflow entirely, the length check should also take the sizeof
entry->array[0] into account, since this array[0] is filled the
length of trace data and occupy addtional space and risk overflow.

Link: https://lkml.kernel.org/r/20210607125734.1770447-1-liangyan.peng@linux.alibaba.com

Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Xunlei Pang <xlpang@linux.alibaba.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: b220c049d519 ("tracing: Check length before giving out the filter buffer")
Reviewed-by: Xunlei Pang <xlpang@linux.alibaba.com>
Reviewed-by: yinbinbin <yinbinbin@alibabacloud.com>
Reviewed-by: Wetp Zhang <wetp.zy@linux.alibaba.com>
Tested-by: James Wang <jnwang@linux.alibaba.com>
Signed-off-by: Liangyan <liangyan.peng@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-16 11:59:46 +02:00
..
bpf bpf: No need to simulate speculative domain for immediates 2021-05-28 13:10:26 +02:00
cgroup cgroup1: don't allow '\n' in renaming 2021-06-16 11:59:40 +02:00
configs kvm_config: add CONFIG_VIRTIO_MENU 2018-10-24 20:55:56 -04:00
debug kdb: Make memory allocations more robust 2021-03-04 10:26:10 +01:00
dma swiotlb: fix "x86: Don't panic if can not alloc buffer for swiotlb" 2020-11-18 19:20:32 +01:00
events perf: Fix data race between pin_count increment/decrement 2021-06-16 11:59:44 +02:00
gcov gcov: re-fix clang-11+ support 2021-04-14 08:24:10 +02:00
irq genirq/matrix: Prevent allocation counter corruption 2021-05-11 14:04:05 +02:00
livepatch livepatch: Nullify obj->mod in klp_module_coming()'s error path 2019-08-19 13:03:37 +02:00
locking locking/mutex: clear MUTEX_FLAGS if wait_list is empty due to signal 2021-05-26 12:05:15 +02:00
power PM: EM: postpone creating the debugfs dir till fs_initcall 2021-03-30 14:35:28 +02:00
printk printk: fix deadlock when kernel panic 2021-03-04 10:26:50 +01:00
rcu rcu/nocb: Perform deferred wake up before last idle's need_resched() check 2021-03-04 10:26:47 +01:00
sched sched/fair: Make sure to update tg contrib for blocked load 2021-06-16 11:59:44 +02:00
time posix-timers: Preserve return value in clock_adjtime32() 2021-05-11 14:04:04 +02:00
trace tracing: Correct the length check which causes memory corruption 2021-06-16 11:59:46 +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 acct_on(): don't mess with freeze protection 2019-04-04 21:04:13 -04:00
async.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441 2019-06-05 17:37:17 +02:00
audit_fsnotify.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
audit_tree.c fsnotify: switch send_to_group() and ->handle_event to const struct qstr * 2019-04-26 13:51:03 -04:00
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: fix a net reference leak in audit_list_rules_send() 2020-06-22 09:30:59 +02:00
audit.h audit: fix a net reference leak in audit_list_rules_send() 2020-06-22 09:30:59 +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: enforce op for string fields 2019-05-28 17:46:43 -04:00
backtracetest.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441 2019-06-05 17:37:17 +02:00
bounds.c kbuild: fix kernel/bounds.c 'W=1' warning 2018-10-31 08:54:14 -07:00
capability.c LSM: add SafeSetID module that gates setid calls 2019-01-25 11:22:43 -08:00
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 kernel/cpu: add arch override for clear_tasks_mm_cpumask() mm handling 2020-12-30 11:50:56 +01:00
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 exec: Transform exec_update_mutex into a rw_semaphore 2021-01-09 13:44:55 +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 Revert 337f13046f ("futex: Allow FUTEX_CLOCK_REALTIME with FUTEX_WAIT op") 2021-05-11 14:04:16 +02:00
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 kcov: convert kcov.refcount to refcount_t 2019-03-07 18:32:02 -08:00
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 kernel: kexec_file: fix error return code of kexec_calculate_store_digests() 2021-05-19 10:08:28 +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 tracing/kprobe: Fix to support kretprobe events on unloaded modules 2021-02-13 13:52:54 +01:00
ksysfs.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 170 2019-05-30 11:26:39 -07:00
kthread.c kthread: Extract KTHREAD_IS_PER_CPU 2021-02-07 15:35:49 +01:00
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 modules: inherit TAINT_PROPRIETARY_MODULE 2021-05-11 14:04:04 +02:00
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 proc/sysctl: add shared variables for range check 2019-07-18 17:08:07 -07:00
pid.c kernel/pid.c: convert struct pid count to refcount_t 2019-07-16 19:23:24 -07:00
profile.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
ptrace.c ptrace: make ptrace() fail if the tracee changed its pid unexpectedly 2021-05-26 12:05:15 +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: Add missing return in non-void function 2021-03-04 10:26:45 +01:00
signal.c ptrace: fix task_join_group_stop() for the case when current is traced 2020-11-10 12:37:24 +01:00
smp.c smp: Fix smp_call_function_single_async prototype 2021-05-14 09:44:33 +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 stackleak: Mark stackleak_track_stack() as notrace 2018-12-05 19:31:44 -08:00
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 arch: handle arches who do not yet define clone3 2019-06-21 01:54:53 +02:00
sys.c kernel/sys.c: avoid copying possible padding bytes in copy_to_user 2020-10-01 13:17:23 +02:00
sysctl_binary.c kernel/sysctl: add panic_print into sysctl 2019-01-04 13:13:47 -08:00
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 sysctl.c: fix underflow value setting risk in vm_table 2021-03-17 17:03:45 +01:00
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: Do not fail unregistering a probe due to memory failure 2021-03-04 10:26:32 +01:00
tsacct.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
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 kernel/watchdog_hld.c: hard lockup message should end with a newline 2019-04-19 09:46:05 -07:00
watchdog.c watchdog/softlockup: Enforce that timestamp is valid on boot 2020-02-24 08:36:52 +01:00
workqueue_internal.h sched/core, workqueues: Distangle worker accounting from rq lock 2019-04-16 16:55:15 +02:00
workqueue.c wq: handle VM suspension in stall detection 2021-06-16 11:59:35 +02:00