CVSS 3.1
Вероятност да бъде експлоатирана в следващите 30 дни (EPSS)
Атакува се
Време до експлоатация
Атакува се локално, без особени условия, с обикновен потребителски вход и без действие от потребителя.
Описание
Оригинално описание
In the Linux kernel, the following vulnerability has been resolved: mfd: qnap-mcu: keep the reply buffer alive past a command timeout qnap_mcu_exec() publishes an on-stack buffer to the receive path: unsigned char rx[QNAP_MCU_RX_BUFFER_SIZE]; ... reply->data = rx; reply->length = length; and qnap_mcu_receive_buf() writes into it from the serdev receive path, which runs out of flush_to_ldisc() and is not serialized against qnap_mcu_exec() at all. bus_lock cannot cover it, because qnap_mcu_exec() holds that mutex across wait_for_completion_timeout(). On a timeout qnap_mcu_exec() returns with reply->data still pointing at its own frame. A reply that arrives late, or an unsolicited message from the MCU, is then written into a stack frame that has been left, corrupting whatever runs next on that stack. The same applies when qnap_mcu_write() fails, since that path returns without touching the reply state either. Move the receive buffer into struct qnap_mcu. It is 37 bytes and the structure is devm_kzalloc()ed, so it lives as long as the driver, and a late write lands in memory that is still valid and is reinitialized by the next command. bus_lock keeps commands from sharing it. This deliberately does not clear reply->data or reply->length on the timeout path. Doing so races with qnap_mcu_receive_buf(), which reads both after its if (!reply->length) return size; check: clearing reply->data gives a NULL dereference, and clearing reply->length alone removes the reply->received == reply->length exit condition, so the copy loop runs until the uart chunk is consumed and overruns the buffer. Leaving both set keeps the write bounded by reply->length, which qnap_mcu_exec() has already checked against sizeof(mcu->rx).
Засегнати продукти
- Linux Linux: 998f70d1806bb718a7565f350283e4a79c8cbb4b преди 0b6680e306397097a97767447368221fac753809; 998f70d1806bb718a7565f350283e4a79c8cbb4b преди 8391ee06d08845a0a165b5fe679ba326915166b2; 998f70d1806bb718a7565f350283e4a79c8cbb4b преди 47504742cea7878ebd1bf1491bbed923df6b90b1
- Linux Linux: 6.14; преди 6.14; 6.18.51 до 6.18.*; 7.2.4 до 7.2.*; от 7.3 нататък
История
- 11 септември 2026 Публикувано
Други уязвимости в Linux Linux
Първоизточници
- https://www.cve.org/CVERecord?id=CVE-2026-80975
- https://nvd.nist.gov/vuln/detail/CVE-2026-80975
- https://git.kernel.org/stable/c/0b6680e306397097a97767447368221fac753809
- https://git.kernel.org/stable/c/8391ee06d08845a0a165b5fe679ba326915166b2
- https://git.kernel.org/stable/c/47504742cea7878ebd1bf1491bbed923df6b90b1