NothingOSS/android_kernel_msm-6.1_nothing_sm7635
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions
android_kernel_msm-6.1_noth.../kernel
History
Mathieu Desnoyers 09a44d994b ring-buffer: Fix 32-bit rb_time_read() race with rb_time_cmpxchg() 
[ Upstream commit dec890089bf79a4954b61482715ee2d084364856 ]

The following race can cause rb_time_read() to observe a corrupted time
stamp:

rb_time_cmpxchg()
[...]
        if (!rb_time_read_cmpxchg(&t->msb, msb, msb2))
                return false;
        if (!rb_time_read_cmpxchg(&t->top, top, top2))
                return false;
<interrupted before updating bottom>
__rb_time_read()
[...]
        do {
                c = local_read(&t->cnt);
                top = local_read(&t->top);
                bottom = local_read(&t->bottom);
                msb = local_read(&t->msb);
        } while (c != local_read(&t->cnt));

        *cnt = rb_time_cnt(top);

        /* If top and msb counts don't match, this interrupted a write */
        if (*cnt != rb_time_cnt(msb))
                return false;
          ^ this check fails to catch that "bottom" is still not updated.

So the old "bottom" value is returned, which is wrong.

Fix this by checking that all three of msb, top, and bottom 2-bit cnt
values match.

The reason to favor checking all three fields over requiring a specific
update order for both rb_time_set() and rb_time_cmpxchg() is because
checking all three fields is more robust to handle partial failures of
rb_time_cmpxchg() when interrupted by nested rb_time_set().

Link: https://lore.kernel.org/lkml/20231211201324.652870-1-mathieu.desnoyers@efficios.com/
Link: https://lore.kernel.org/linux-trace-kernel/20231212193049.680122-1-mathieu.desnoyers@efficios.com

Fixes: f458a1453424e ("ring-buffer: Test last update in 32bit version of __rb_time_read()")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:35 +01:00
..
bpf bpf: fix precision backtracking instruction iteration 2024-01-10 17:10:29 +01:00
cgroup cgroup_freezer: cgroup_freezing: Check if not frozen 2023-12-13 18:39:19 +01:00
configs Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
debug kgdb: Flush console before entering kgdb on panic 2023-11-28 17:07:02 +00:00
dma dma-debug: don't call __dma_entry_alloc_check_leak() under free_entries_lock 2023-10-06 14:56:50 +02:00
entry entry/rcu: Check TIF_RESCHED _after_ delayed RCU wake-up 2023-03-30 12:49:13 +02:00
events perf: Fix perf_event_validate_size() lockdep splat 2023-12-20 17:00:24 +01:00
futex futex: Don't include process MM in futex key on no-MMU 2023-11-20 11:51:50 +01:00
gcov gcov: add support for checksum field 2022-12-31 13:33:11 +01:00
irq genirq/affinity: Move group_cpus_evenly() into lib/ 2024-01-10 17:10:33 +01:00
kcsan kcsan: Don't expect 64 bits atomic builtins from 32 bits architectures 2023-07-19 16:21:37 +02:00
livepatch livepatch: Fix missing newline character in klp_resolve_symbols() 2023-11-20 11:52:10 +01:00
locking lockdep: Fix block chain corruption 2023-12-03 07:32:09 +01:00
module kallsyms: Make module_kallsyms_on_each_symbol generally available 2024-01-05 15:18:40 +01:00
power PM: hibernate: Clean up sync_read handling in snapshot_write_next() 2023-11-28 17:07:11 +00:00
printk printk: Consolidate console deferred printing 2023-09-23 11:11:07 +02:00
rcu srcu: Fix callbacks acceleration mishandling 2024-01-10 17:10:26 +01:00
sched sched: Fix stop_one_cpu_nowait() vs hotplug 2023-11-20 11:51:50 +01:00
time hrtimers: Push pending hrtimers away from outgoing CPU earlier 2023-12-13 18:39:03 +01:00
trace ring-buffer: Fix 32-bit rb_time_read() race with rb_time_cmpxchg() 2024-01-10 17:10:35 +01:00
.gitignore
acct.c acct: fix potential integer overflow in encode_comp_t() 2022-12-31 13:32:58 +01:00
async.c
audit.c audit: use time_after to compare time 2022-08-29 19:47:03 -04:00
audit.h audit: remove selinux_audit_rule_update() declaration 2022-09-07 11:30:15 -04:00
audit_fsnotify.c audit: fix potential double free on error path from fsnotify_add_inode_mark 2022-08-22 18:50:06 -04:00
audit_tree.c audit: use fsnotify group lock helpers 2022-04-25 14:37:28 +02:00
audit_watch.c audit: don't WARN_ON_ONCE(!current->mm) in audit_exe_compare() 2023-11-28 17:07:08 +00:00
auditfilter.c
auditsc.c audit,io_uring: io_uring openat triggers audit reference count underflow 2023-10-25 12:03:04 +02:00
backtracetest.c
bounds.c mm: multi-gen LRU: minimal implementation 2022-09-26 19:46:09 -07:00
capability.c
cfi.c cfi: Switch to -fsanitize=kcfi 2022-09-26 10:13:13 -07:00
compat.c sched_getaffinity: don't assume 'cpumask_size()' is fully initialized 2023-04-06 12:10:40 +02:00
configs.c
context_tracking.c context_tracking: Fix noinstr vs KASAN 2023-03-10 09:33:45 +01:00
cpu.c cpu/SMT: Make SMT control more robust against enumeration failures 2024-01-10 17:10:26 +01:00
cpu_pm.c context_tracking: Take IRQ eqs entrypoints over RCU 2022-07-05 13:32:59 -07:00
crash_core.c vmcoreinfo: add kallsyms_num_syms symbol 2022-08-28 14:02:44 -07:00
crash_dump.c
cred.c cred: switch to using atomic_long_t 2023-12-20 17:00:20 +01:00
delayacct.c delayacct: support re-entrance detection of thrashing accounting 2022-09-26 19:46:07 -07:00
dma.c
exec_domain.c
exit.c exit: Detect and fix irq disabled state in oops 2023-03-10 09:33:45 +01:00
extable.c context_tracking: Take NMI eqs entrypoints over RCU 2022-07-05 13:32:59 -07:00
fail_function.c kernel/fail_function: fix memory leak with using debugfs_lookup() 2023-03-11 13:55:39 +01:00
fork.c kernel/fork: beware of __put_task_struct() calling context 2023-09-23 11:11:00 +02:00
freezer.c freezer,sched: Rewrite core freezer logic 2022-09-07 21:53:50 +02:00
gen_kheaders.sh kbuild: build init/built-in.a just once 2022-09-29 04:40:15 +09:00
groups.c security: Add LSM hook to setgroups() syscall 2022-07-15 18:21:49 +00:00
hung_task.c sched: Fix more TASK_state comparisons 2022-09-30 16:50:39 +02:00
iomem.c
irq_work.c irq_work: use kasan_record_aux_stack_noalloc() record callstack 2022-04-15 14:49:55 -07:00
jump_label.c jump_label: make initial NOP patching the special case 2022-06-24 09:48:55 +02:00
kallsyms.c kallsyms: Add helper kallsyms_on_each_match_symbol() 2023-10-25 12:03:16 +02:00
kallsyms_internal.h kallsyms: Reduce the memory occupied by kallsyms_seqs_of_names[] 2023-10-25 12:03:16 +02:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt Revert "signal, x86: Delay calling signals in atomic on RT enabled kernels" 2022-03-31 10:36:55 +02:00
kcov.c kcov: kmsan: unpoison area->list in kcov_remote_area_put() 2022-10-03 14:03:23 -07:00
kexec.c kernel: kexec: copy user-array safely 2023-11-28 17:06:57 +00:00
kexec_core.c kexec: fix a memory leak in crash_shrink_memory() 2023-07-19 16:21:08 +02:00
kexec_elf.c
kexec_file.c kexec: support purgatories with .text.hot sections 2023-06-21 16:00:55 +02:00
kexec_internal.h panic, kexec: make __crash_kexec() NMI safe 2022-09-11 21:55:06 -07:00
kheaders.c kheaders: Use array declaration instead of char 2023-05-11 23:03:02 +09:00
kmod.c
kprobes.c kprobes: consistent rcu api usage for kretprobe holder 2023-12-13 18:39:17 +01:00
ksysfs.c kexec: turn all kexec_mutex acquisitions into trylocks 2022-09-11 21:55:06 -07:00
kthread.c signal: break out of wait loops on kthread_stop() 2022-10-09 16:01:59 -07:00
latencytop.c latencytop: use the last element of latency_record of system 2022-09-11 21:55:12 -07:00
Makefile cfi: Fix CFI failure with KASAN 2022-12-31 13:33:08 +01:00
module_signature.c
notifier.c notifier: Add blocking/atomic_notifier_chain_register_unique_prio() 2022-05-19 19:30:30 +02:00
nsproxy.c Revert "fs/exec: allow to unshare a time namespace on vfork+exec" 2022-09-13 10:38:43 -07:00
padata.c crypto: pcrypt - Fix hungtask for PADATA_RESET 2023-11-28 17:06:58 +00:00
panic.c panic: Reenable preemption in WARN slowpath 2023-09-23 11:11:09 +02:00
params.c
pid.c gfs2: Add glockfd debugfs file 2022-06-29 13:07:16 +02:00
pid_namespace.c rcu-tasks: Fix synchronize_rcu_tasks() VS zap_pid_ns_processes() 2023-03-10 09:32:52 +01:00
profile.c kernel/profile.c: simplify duplicated code in profile_setup() 2022-09-11 21:55:12 -07:00
ptrace.c freezer,sched: Rewrite core freezer logic 2022-09-07 21:53:50 +02:00
range.c
reboot.c kernel/reboot: emergency_restart: Set correct system_state 2023-11-28 17:07:13 +00:00
regset.c
relay.c relayfs: fix out-of-bounds access in relay_file_read 2023-05-11 23:03:03 +09:00
resource.c PCI: Allow drivers to request exclusive config regions 2023-09-13 09:42:46 +02:00
resource_kunit.c
rseq.c rseq: Use pr_warn_once() when deprecated/unknown ABI flags are encountered 2022-11-14 09:58:32 +01:00
scftorture.c scftorture: Forgive memory-allocation failure if KASAN 2023-09-23 11:11:00 +02:00
scs.c kasan, vmalloc: only tag normal vmalloc allocations 2022-03-24 19:06:48 -07:00
seccomp.c seccomp: Add wait_killable semantic to seccomp user notifier 2022-05-03 14:11:58 -07:00
signal.c mm: suppress mm fault logging if fatal signal already pending 2023-08-03 10:24:01 +02:00
smp.c smp,csd: Throw an error if a CSD lock is stuck for too long 2023-11-28 17:06:55 +00:00
smpboot.c smpboot: use atomic_try_cmpxchg in cpu_wait_death and cpu_report_death 2022-09-11 21:55:10 -07:00
smpboot.h
softirq.c context_tracking: Take IRQ eqs entrypoints over RCU 2022-07-05 13:32:59 -07:00
stackleak.c stackleak: add on/off stack variants 2022-05-08 01:33:09 -07:00
stacktrace.c
static_call.c static_call: Don't make __static_call_return0 static 2022-04-05 09:59:38 +02:00
static_call_inline.c static_call: Don't make __static_call_return0 static 2022-04-05 09:59:38 +02:00
stop_machine.c Scheduler changes in this cycle were: 2022-05-24 11:11:13 -07:00
sys.c kernel/sys.c: fix and improve control flow in __sys_setres[ug]id() 2023-04-26 14:28:39 +02:00
sys_ni.c kernel/sys_ni: add compat entry for fadvise64_64 2022-08-20 15:17:45 -07:00
sysctl-test.c kernel/sysctl-test: use SYSCTL_{ZERO/ONE_HUNDRED} instead of i_{zero/one_hundred} 2022-09-08 16:56:45 -07:00
sysctl.c proc: proc_skip_spaces() shouldn't think it is working on C strings 2022-12-05 12:09:06 -08:00
task_work.c task_work: use try_cmpxchg in task_work_add, task_work_cancel_match and task_work_run 2022-09-11 21:55:10 -07:00
taskstats.c genetlink: start to validate reserved header bytes 2022-08-29 12:47:15 +01:00
torture.c torture: Fix hang during kthread shutdown phase 2023-03-10 09:34:07 +01:00
tracepoint.c tracepoint: Optimize the critical region of mutex_lock in tracepoint_module_coming() 2022-09-26 13:01:18 -04:00
tsacct.c taskstats: version 12 with thread group and exe info 2022-04-29 14:38:03 -07:00
ucount.c ucounts: Split rlimit and ucount values and max values 2022-05-18 18:24:57 -05:00
uid16.c
uid16.h
umh.c freezer,umh: Fix call_usermode_helper_exec() vs SIGKILL 2023-02-22 12:59:50 +01:00
up.c
user-return-notifier.c
user.c
user_namespace.c ucounts: Split rlimit and ucount values and max values 2022-10-09 16:24:05 -07:00
usermode_driver.c blob_to_mnt(): kern_unmount() is needed to undo kern_mount() 2022-05-19 23:25:47 -04:00
utsname.c
utsname_sysctl.c kernel/utsname_sysctl.c: Fix hostname polling 2022-10-23 12:01:01 -07:00
watch_queue.c kernel: watch_queue: copy user-array safely 2023-11-28 17:06:57 +00:00
watchdog.c watchdog: move softlockup_panic back to early_param 2023-11-28 17:07:09 +00:00
watchdog_hld.c watchdog/perf: more properly prevent false positives with turbo modes 2023-07-19 16:21:08 +02:00
workqueue.c workqueue: Provide one lock class key per work_on_cpu() callsite 2023-11-28 17:06:55 +00:00
workqueue_internal.h