Vulnerabilidad · Publicado 25/06/2026 · Actualizado 01/08/2026
In the Linux kernel, the following vulnerability has been resolved:
accel/ethosu: reject DMA commands with uninitialized length
cmd_state_init() initializes the command state with memset(0xff),
leaving dma->len at U64_MAX to signal missing setup. The only setter
is NPU_SET_DMA0_LEN; if userspace omits this command and issues
NPU_OP_DMA_START, dma->len remains U64_MAX.
In dma_length(), a positiv…
In the Linux kernel, the following vulnerability has been resolved: accel/ethosu: reject DMA commands with uninitialized length cmd_state_init() initializes the command state with memset(0xff), leaving dma->len at U64_MAX to signal missing setup. The only setter is NPU_SET_DMA0_LEN; if userspace omits this command and issues NPU_OP_DMA_START, dma->len remains U64_MAX. In dma_length(), a positive stride added to U64_MAX wraps to a small value. With size0 == 1, check_mul_overflow() does not trigger and dma_length() returns 0 instead of U64_MAX. The caller's U64_MAX check then passes, region_size[] stays 0, and the bounds check in ethosu_job.c is bypassed, allowing hardware to execute DMA with stale physical addresses. Fix by checking for U64_MAX at the start of dma_length() before any arithmetic, consistent with the sentinel value used throughout the driver to detect uninitialized fields.
Score: 8.8/10 — Severidad: HIGH — Estado NIST: Analyzed
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Linux kernel — Linux
CWE-908
Publicado en NIST NVD.