CVE-2026-53173

Summary

In the Linux kernel, the following vulnerability has been resolved:

accel/ethosu: fix OOB write in ethosu_gem_cmdstream_copy_and_validate()

The command stream parsing loop increments the index variable a second time when a 64-bit command word is encountered (bit 14 set), but does not re-check the loop bound before writing the second word:

for (i = 0; i < size / 4; i++) {
    bocmds[i] = cmds[0];
    if (cmd & 0x4000) {
        i++;
        bocmds[i] = cmds[1];   /* unchecked */
    }
}

The buffer bocmds is backed by a DMA allocation of exactly size bytes from drm_gem_dma_create(ddev, size), giving valid indices [0, size/4-1].

When i == size/4 - 1 on entry to an iteration and bit 14 of cmds[0] is set, bocmds[size/4-1] is written in bounds, i is then incremented to size/4, and bocmds[size/4] writes four bytes past the end of the allocation.

Userspace controls both the buffer contents and the size argument via the ioctl, making this a userspace-triggerable heap out-of-bounds write.

Fix by checking the incremented index against the buffer bound before the second write and returning -EINVAL if the buffer is too small to contain the extended command.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux5a5e9c0228e613f0ef2a58b9782d7c0ea8f1e58b < db6cb3e35cebf487f9a78ebd4cfa4b83708ff40daffected
LinuxLinux5a5e9c0228e613f0ef2a58b9782d7c0ea8f1e58b < c0837b9cf6eabbad8b8cbddaff1a46a6d0a2e29daffected
LinuxLinux6.19affected
LinuxLinux0 < 6.19unaffected
LinuxLinux7.0.13 <= 7.0.*unaffected
LinuxLinux7.1 <= *unaffected

Weaknesses

References