Описание
In the Linux kernel, the following vulnerability has been resolved:
printk: Fix possible console use-after-free
When emitting a record via legacy printing, it is possible that a handover
to another legacy printing context occurs. When a context has performed a
handover, the console SRCU read lock is released and the pointer to the
console struct might now be invalid. Therefore, after calling
nbcon_legacy_emit_next_record() or console_emit_next_record(), it is
necessary to check if a handover occurred before further @con usage.
Sashiko pointed out that console_flush_one_record() was not doing this.
In console_flush_one_record(), after emitting a record, move the further
usage of @con after the handover check.
A flaw was found in the Linux kernel. When the printk function handles legacy console printing, a specific scenario involving context handover can lead to a use-after-free vulnerability. This occurs because the system fails to verify if a memory area has been freed after a handover, potentially allowing an attacker to corrupt memory. This could result in a denial of service or, in more severe cases, arbitrary code execution.
Отчет
This vulnerability is rated as having a Moderate severity because exploitation requires local access to trigger concurrent console logging events, and the primary impact is limited to a local denial of service via kernel crash. The issue stems from unsynchronized console pointer access during printing context handovers under heavy concurrent logging. Earlier platform releases, such as Red Hat Enterprise Linux 8 and 9, are unaffected because they lack the underlying console handover implementation.
Меры по смягчению последствий
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat Enterprise Linux 10 | kernel | Fix deferred | ||
| Red Hat Enterprise Linux 6 | kernel | Not affected | ||
| Red Hat Enterprise Linux 7 | kernel | Not affected | ||
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | ||
| Red Hat Enterprise Linux 8 | kernel | Not affected | ||
| Red Hat Enterprise Linux 8 | kernel-rt | Not affected | ||
| Red Hat Enterprise Linux 9 | kernel | Not affected | ||
| Red Hat Enterprise Linux 9 | kernel-rt | Not affected | ||
| Red Hat OpenShift Container Platform 4 | openshift/ose-rhel-coreos-8 | Not affected | ||
| Red Hat OpenShift Container Platform 4 | openshift/ose-rhel-coreos-9 | Not affected |
Показывать по
Дополнительная информация
Статус:
EPSS
5.5 Medium
CVSS3
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: printk: Fix possible console use-after-free When emitting a record via legacy printing, it is possible that a handover to another legacy printing context occurs. When a context has performed a handover, the console SRCU read lock is released and the pointer to the console struct might now be invalid. Therefore, after calling nbcon_legacy_emit_next_record() or console_emit_next_record(), it is necessary to check if a handover occurred _before_ further @con usage. Sashiko pointed out that console_flush_one_record() was not doing this. In console_flush_one_record(), after emitting a record, move the further usage of @con after the handover check.
In the Linux kernel, the following vulnerability has been resolved: printk: Fix possible console use-after-free When emitting a record via legacy printing, it is possible that a handover to another legacy printing context occurs. When a context has performed a handover, the console SRCU read lock is released and the pointer to the console struct might now be invalid. Therefore, after calling nbcon_legacy_emit_next_record() or console_emit_next_record(), it is necessary to check if a handover occurred _before_ further @con usage. Sashiko pointed out that console_flush_one_record() was not doing this. In console_flush_one_record(), after emitting a record, move the further usage of @con after the handover check.
In the Linux kernel, the following vulnerability has been resolved: p ...
In the Linux kernel, the following vulnerability has been resolved: printk: Fix possible console use-after-free When emitting a record via legacy printing, it is possible that a handover to another legacy printing context occurs. When a context has performed a handover, the console SRCU read lock is released and the pointer to the console struct might now be invalid. Therefore, after calling nbcon_legacy_emit_next_record() or console_emit_next_record(), it is necessary to check if a handover occurred _before_ further @con usage. Sashiko pointed out that console_flush_one_record() was not doing this. In console_flush_one_record(), after emitting a record, move the further usage of @con after the handover check.
EPSS
5.5 Medium
CVSS3