Описание
In the Linux kernel, the following vulnerability has been resolved:
i2c: i801: fix hardware state machine corruption in error path
A severe livelock and subsequent Hung Task panic were observed in the
i2c-i801 driver during concurrent Fuzzing. The crash is caused by an
unconditional hardware register cleanup in the error handling path of
i801_access().
When i801_check_pre() fails (e.g., returning -EBUSY because the SMBus
controller is actively used by BIOS/ACPI), the kernel does not actually
acquire the hardware ownership. However, the code jumps to the 'out'
label and executes:
iowrite8(SMBHSTSTS_INUSE_STS | STATUS_FLAGS, SMBHSTSTS(priv));
This forcefully clears the INUSE_STS lock and resets the hardware status
flags without owning the controller. Doing so interrupts ongoing BIOS/ACPI
transactions and totally corrupts the SMBus hardware state machine.
Consequently, all subsequent i801_access() calls fail at the pre-check
stage, triggering an endless stream of "SMBus is busy, can't use it!"
error logs. Over a slow serial console, this printk flood monopolizes
the CPU (Console Livelock), starving other processes trying to acquire
the mmap_lock down_read semaphore, ultimately triggering the hung task
watchdog.
Fix this by moving the 'out' label below the hardware register cleanup.
If i801_check_pre() fails, we safely bypass the iowrite8() and only
release the software locks (pm_runtime and mutex), strictly adhering to
the rule of not releasing resources that were never acquired.
A flaw was found in the Linux kernel's i2c-i801 driver. This vulnerability allows a local attacker to trigger a hardware state machine corruption during error handling. This can lead to a denial of service (DoS), where the system becomes unresponsive due to a continuous stream of error messages and CPU resource exhaustion.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat Enterprise Linux 10 | kernel | Fix deferred | ||
| Red Hat Enterprise Linux 6 | kernel | Out of support scope | ||
| 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 | Fix deferred | ||
| Red Hat Enterprise Linux 9 | kernel-rt | Fix deferred |
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Дополнительная информация
Статус:
EPSS
5.5 Medium
CVSS3
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: i2c: i801: fix hardware state machine corruption in error path A severe livelock and subsequent Hung Task panic were observed in the i2c-i801 driver during concurrent Fuzzing. The crash is caused by an unconditional hardware register cleanup in the error handling path of i801_access(). When i801_check_pre() fails (e.g., returning -EBUSY because the SMBus controller is actively used by BIOS/ACPI), the kernel does not actually acquire the hardware ownership. However, the code jumps to the 'out' label and executes: iowrite8(SMBHSTSTS_INUSE_STS | STATUS_FLAGS, SMBHSTSTS(priv)); This forcefully clears the INUSE_STS lock and resets the hardware status flags without owning the controller. Doing so interrupts ongoing BIOS/ACPI transactions and totally corrupts the SMBus hardware state machine. Consequently, all subsequent i801_access() calls fail at the pre-check stage, triggering an endless stream of "SMBus is busy, can't ...
In the Linux kernel, the following vulnerability has been resolved: i2c: i801: fix hardware state machine corruption in error path A severe livelock and subsequent Hung Task panic were observed in the i2c-i801 driver during concurrent Fuzzing. The crash is caused by an unconditional hardware register cleanup in the error handling path of i801_access(). When i801_check_pre() fails (e.g., returning -EBUSY because the SMBus controller is actively used by BIOS/ACPI), the kernel does not actually acquire the hardware ownership. However, the code jumps to the 'out' label and executes: iowrite8(SMBHSTSTS_INUSE_STS | STATUS_FLAGS, SMBHSTSTS(priv)); This forcefully clears the INUSE_STS lock and resets the hardware status flags without owning the controller. Doing so interrupts ongoing BIOS/ACPI transactions and totally corrupts the SMBus hardware state machine. Consequently, all subsequent i801_access() calls fail at the pre-check stage, triggering an endless stream of "SMBus is busy,
In the Linux kernel, the following vulnerability has been resolved: i ...
In the Linux kernel, the following vulnerability has been resolved: i2c: i801: fix hardware state machine corruption in error path A severe livelock and subsequent Hung Task panic were observed in the i2c-i801 driver during concurrent Fuzzing. The crash is caused by an unconditional hardware register cleanup in the error handling path of i801_access(). When i801_check_pre() fails (e.g., returning -EBUSY because the SMBus controller is actively used by BIOS/ACPI), the kernel does not actually acquire the hardware ownership. However, the code jumps to the 'out' label and executes: iowrite8(SMBHSTSTS_INUSE_STS | STATUS_FLAGS, SMBHSTSTS(priv)); This forcefully clears the INUSE_STS lock and resets the hardware status flags without owning the controller. Doing so interrupts ongoing BIOS/ACPI transactions and totally corrupts the SMBus hardware state machine. Consequently, all subsequent i801_access() calls fail at the pre-check stage, triggering an endless stream of "SMBus is bu...
EPSS
5.5 Medium
CVSS3