Subject: CVE-2024-45012: nouveau/firmware: use dma non-coherent allocator

From: Greg Kroah-Hartman <[email-masked]>

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

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

nouveau/firmware: use dma non-coherent allocator

Currently, enabling SG_DEBUG in the kernel will cause nouveau to hit a
BUG() on startup, when the iommu is enabled:

kernel BUG at include/linux/scatterlist.h:187!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 7 PID: 930 Comm: (udev-worker) Not tainted 6.9.0-rc3Lyude-Test+ #30
Hardware name: MSI MS-7A39/A320M GAMING PRO (MS-7A39), BIOS 1.I0 01/22/2019
RIP: 0010:sg_init_one+0x85/0xa0
Code: 69 88 32 01 83 e1 03 f6 c3 03 75 20 a8 01 75 1e 48 09 cb 41 89 54
24 08 49 89 1c 24 41 89 6c 24 0c 5b 5d 41 5c e9 7b b9 88 00 <0f> 0b 0f 0b
0f 0b 48 8b 05 5e 46 9a 01 eb b2 66 66 2e 0f 1f 84 00
RSP: 0018:ffffa776017bf6a0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffa77600d87000 RCX: 000000000000002b
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffffa77680d87000
RBP: 000000000000e000 R08: 0000000000000000 R09: 0000000000000000
R10: ffff98f4c46aa508 R11: 0000000000000000 R12: ffff98f4c46aa508
R13: ffff98f4c46aa008 R14: ffffa77600d4a000 R15: ffffa77600d4a018
FS:  00007feeb5aae980(0000) GS:ffff98f5c4dc0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f22cb9a4520 CR3: 00000001043ba000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 ? die+0x36/0x90
 ? do_trap+0xdd/0x100
 ? sg_init_one+0x85/0xa0
 ? do_error_trap+0x65/0x80
 ? sg_init_one+0x85/0xa0
 ? exc_invalid_op+0x50/0x70
 ? sg_init_one+0x85/0xa0
 ? asm_exc_invalid_op+0x1a/0x20
 ? sg_init_one+0x85/0xa0
 nvkm_firmware_ctor+0x14a/0x250 [nouveau]
 nvkm_falcon_fw_ctor+0x42/0x70 [nouveau]
 ga102_gsp_booter_ctor+0xb4/0x1a0 [nouveau]
 r535_gsp_oneinit+0xb3/0x15f0 [nouveau]
 ? srso_return_thunk+0x5/0x5f
 ? srso_return_thunk+0x5/0x5f
 ? nvkm_udevice_new+0x95/0x140 [nouveau]
 ? srso_return_thunk+0x5/0x5f
 ? srso_return_thunk+0x5/0x5f
 ? ktime_get+0x47/0xb0

Fix this by using the non-coherent allocator instead, I think there
might be a better answer to this, but it involve ripping up some of
APIs using sg lists.

The Linux kernel CVE team has assigned CVE-2024-45012 to this issue.

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

	Issue introduced in 6.2 with commit 2541626cfb79 and fixed in 6.6.48 with commit cc29c5546c6a
	Issue introduced in 6.2 with commit 2541626cfb79 and fixed in 6.10.7 with commit 57ca481fca97
	Issue introduced in 6.2 with commit 2541626cfb79 and fixed in 6.11 with commit 9b340aeb26d5

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-2024-45012
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/gpu/drm/nouveau/nvkm/core/firmware.c
	drivers/gpu/drm/nouveau/nvkm/falcon/fw.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/cc29c5546c6a373648363ac49781f1d74b530707
	https://git.kernel.org/stable/c/57ca481fca97ca4553e8c85d6a94baf4cb40c40e
	https://git.kernel.org/stable/c/9b340aeb26d50e9a9ec99599e2a39b035fac978e