CVE-2025-40311: accel/habanalabs: support mapping cb with vmalloc-backed coherent memory

CVE-2025-40311: accel/habanalabs: support mapping cb with vmalloc-backed coherent memory

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

Description
===========

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

accel/habanalabs: support mapping cb with vmalloc-backed coherent memory

When IOMMU is enabled, dma_alloc_coherent() with GFP_USER may return
addresses from the vmalloc range. If such an address is mapped without
VM_MIXEDMAP, vm_insert_page() will trigger a BUG_ON due to the
VM_PFNMAP restriction.

Fix this by checking for vmalloc addresses and setting VM_MIXEDMAP
in the VMA before mapping. This ensures safe mapping and avoids kernel
crashes. The memory is still driver-allocated and cannot be accessed
directly by userspace.

The Linux kernel CVE team has assigned CVE-2025-40311 to this issue.


Affected and fixed versions
===========================

	Fixed in 6.6.117 with commit 7ec8ac9f73d4a9438c2186768d6de27ace37531e
	Fixed in 6.12.58 with commit d1dfe21a332d38a6a09658ec29a55940afb5fe36
	Fixed in 6.17.8 with commit 73c7c2cdb442fc4160d2a2a4bfffbd162af06cb9
	Fixed in 6.18 with commit 513024d5a0e34fd34247043f1876b6138ca52847

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2025-40311
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/accel/habanalabs/gaudi/gaudi.c
	drivers/accel/habanalabs/gaudi2/gaudi2.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/7ec8ac9f73d4a9438c2186768d6de27ace37531e
	https://git.kernel.org/stable/c/d1dfe21a332d38a6a09658ec29a55940afb5fe36
	https://git.kernel.org/stable/c/73c7c2cdb442fc4160d2a2a4bfffbd162af06cb9
	https://git.kernel.org/stable/c/513024d5a0e34fd34247043f1876b6138ca52847