CVE-2026-63960: Linux Kernel: güvenlik açığı

Açıklama (NVD)

In the Linux kernel, the following vulnerability has been resolved: usb: typec: wcove: don't write past struct pd_message in wcove_read_rx_buffer() wcove_read_rx_buffer() copies the PD RX FIFO into the caller's struct pd_message with for (i = 0; i < USBC_RXINFO_RXBYTES(info); i++) regmap_read(wcove->regmap, USBC_RX_DATA + i, msg + i); which has two problems: USBC_RXINFO_RXBYTES() is a 5-bit field (max 31) while struct pd_message is 30 bytes (__le16 header + __le32 payload[PD_MAX_PAYLOAD], packed). The byte count latched in RXINFO is the number of bytes the port partner put on the wire, so a malicious partner that transmits a 31-byte frame can drive the loop one byte past the destination if the WCOVE BMC receiver does not enforce the PD object-count limit in hardware. The existing FIXME flagged this as unverified. Independently, regmap_read() takes an unsigned int * and stores a full unsigned int at the destination. Passing the byte pointer msg + i means each iteration writes four bytes; the high three are zero (val_bits is 8) and are normally overwritten by the next iteration, but the final iteration's high bytes are not. With RXBYTES == 30 the i == 29 iteration already writes three zero bytes past msg, which sits on the IRQ thread's stack in wcove_typec_irq(). Clamp the loop to sizeof(struct pd_message) and read each register into a local before storing only its low byte, so the copy can never exceed the destination regardless of what RXINFO reports.

Özet bilgiler

Ürün

Linux Linux Kernel

CVSS v3.1

5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS

%0,16 (yüzdelik 5)

Yama

Mevcut

Etkilenen sürümler

Kaynaklar

• NVD kaydı
• git.kernel.org
• git.kernel.org
• git.kernel.org
• git.kernel.org
• git.kernel.org
• git.kernel.org
• git.kernel.org
• git.kernel.org