Описание
In the Linux kernel, the following vulnerability has been resolved: rtmutex: Use waiter::task instead of current in remove_waiter() remove_waiter() is used by the slowlock paths, but it is also used for proxy-lock rollback in rt_mutex_start_proxy_lock() when invoked from futex_requeue(). In the latter case waiter::task is not current, but remove_waiter() operates on current for the dequeue operation. That results in several problems:
- the rbtree dequeue happens without waiter::task::pi_lock being held
- the waiter task's pi_blocked_on state is not cleared, which leaves a dangling pointer primed for UAF around.
- rt_mutex_adjust_prio_chain() operates on the wrong top priority waiter
task
Use waiter::task instead of current in all related operations in
remove_waiter() to cure those problems.
[ tglx: Fixup rt_mutex_adjust_prio_chain(), add a comment and amend the
changelog ]
A flaw was found in the Linux kernel. When the kernel's real-time mutex (rtmutex) component performs a specific operation called 'proxy-lock rollback' during futex requeue, it incorrectly handles task pointers. This can lead to a 'Use-After-Free' (UAF) vulnerability, where the system attempts to use memory that has already been released. A local attacker could potentially exploit this to gain elevated privileges or execute unauthorized code.
Меры по смягчению последствий
See the security bulletin for a detailed mitigation procedure.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat Enterprise Linux 9 | kernel-rt | Affected | ||
| NVIDIA for RHEL 10 | kernel | Fixed | RHSA-2026:37728 | 10.07.2026 |
| Red Hat Enterprise Linux 10 | kernel | Fixed | RHSA-2026:38492 | 13.07.2026 |
| Red Hat Enterprise Linux 10 | kpatch-patch | Fixed | RHSA-2026:59143 | 24.08.2026 |
| Red Hat Enterprise Linux 10.0 Extended Update Support | kernel | Fixed | RHSA-2026:41062 | 16.07.2026 |
| Red Hat Enterprise Linux 6 Extended Lifecycle Support - EXTENSION | kernel | Fixed | RHSA-2026:41920 | 20.07.2026 |
| Red Hat Enterprise Linux 7 Extended Lifecycle Support | kernel-rt | Fixed | RHSA-2026:41234 | 17.07.2026 |
| Red Hat Enterprise Linux 7 Extended Lifecycle Support | kernel | Fixed | RHSA-2026:41235 | 17.07.2026 |
| Red Hat Enterprise Linux 8 | kernel-rt | Fixed | RHSA-2026:39082 | 14.07.2026 |
| Red Hat Enterprise Linux 8 | kernel | Fixed | RHSA-2026:39083 | 14.07.2026 |
Показывать по
Дополнительная информация
Статус:
EPSS
7.8 High
CVSS3
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: rtmutex: Use waiter::task instead of current in remove_waiter() remove_waiter() is used by the slowlock paths, but it is also used for proxy-lock rollback in rt_mutex_start_proxy_lock() when invoked from futex_requeue(). In the latter case waiter::task is not current, but remove_waiter() operates on current for the dequeue operation. That results in several problems: 1) the rbtree dequeue happens without waiter::task::pi_lock being held 2) the waiter task's pi_blocked_on state is not cleared, which leaves a dangling pointer primed for UAF around. 3) rt_mutex_adjust_prio_chain() operates on the wrong top priority waiter task Use waiter::task instead of current in all related operations in remove_waiter() to cure those problems. [ tglx: Fixup rt_mutex_adjust_prio_chain(), add a comment and amend the changelog ]
In the Linux kernel, the following vulnerability has been resolved: rtmutex: Use waiter::task instead of current in remove_waiter() remove_waiter() is used by the slowlock paths, but it is also used for proxy-lock rollback in rt_mutex_start_proxy_lock() when invoked from futex_requeue(). In the latter case waiter::task is not current, but remove_waiter() operates on current for the dequeue operation. That results in several problems: 1) the rbtree dequeue happens without waiter::task::pi_lock being held 2) the waiter task's pi_blocked_on state is not cleared, which leaves a dangling pointer primed for UAF around. 3) rt_mutex_adjust_prio_chain() operates on the wrong top priority waiter task Use waiter::task instead of current in all related operations in remove_waiter() to cure those problems. [ tglx: Fixup rt_mutex_adjust_prio_chain(), add a comment and amend the changelog ]
rtmutex: Use waiter::task instead of current in remove_waiter()
In the Linux kernel, the following vulnerability has been resolved: r ...
In the Linux kernel, the following vulnerability has been resolved: rtmutex: Use waiter::task instead of current in remove_waiter() remove_waiter() is used by the slowlock paths, but it is also used for proxy-lock rollback in rt_mutex_start_proxy_lock() when invoked from futex_requeue(). In the latter case waiter::task is not current, but remove_waiter() operates on current for the dequeue operation. That results in several problems: 1) the rbtree dequeue happens without waiter::task::pi_lock being held 2) the waiter task's pi_blocked_on state is not cleared, which leaves a dangling pointer primed for UAF around. 3) rt_mutex_adjust_prio_chain() operates on the wrong top priority waiter task Use waiter::task instead of current in all related operations in remove_waiter() to cure those problems. [ tglx: Fixup rt_mutex_adjust_prio_chain(), add a comment and amend the changelog ]
EPSS
7.8 High
CVSS3