CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
AI Score
Confidence
Low
EPSS
Percentile
5.0%
In the Linux kernel, the following vulnerability has been resolved:
drm/fbdev-dma: Only set smem_start is enable per module option
Only export struct fb_info.fix.smem_start if that is required by the
user and the memory does not come from vmalloc().
Setting struct fb_info.fix.smem_start breaks systems where DMA
memory is backed by vmalloc address space. An example error is
shown below.
[ 3.536043] ------------[ cut here ]------------
[ 3.540716] virt_to_phys used for non-linear address: 000000007fc4f540 (0xffff800086001000)
[ 3.552628] WARNING: CPU: 4 PID: 61 at arch/arm64/mm/physaddr.c:12 __virt_to_phys+0x68/0x98
[ 3.565455] Modules linked in:
[ 3.568525] CPU: 4 PID: 61 Comm: kworker/u12:5 Not tainted 6.6.23-06226-g4986cc3e1b75-dirty #250
[ 3.577310] Hardware name: NXP i.MX95 19X19 board (DT)
[ 3.582452] Workqueue: events_unbound deferred_probe_work_func
[ 3.588291] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=–)
[ 3.595233] pc : __virt_to_phys+0x68/0x98
[ 3.599246] lr : __virt_to_phys+0x68/0x98
[ 3.603276] sp : ffff800083603990
[ 3.677939] Call trace:
[ 3.680393] __virt_to_phys+0x68/0x98
[ 3.684067] drm_fbdev_dma_helper_fb_probe+0x138/0x238
[ 3.689214] __drm_fb_helper_initial_config_and_unlock+0x2b0/0x4c0
[ 3.695385] drm_fb_helper_initial_config+0x4c/0x68
[ 3.700264] drm_fbdev_dma_client_hotplug+0x8c/0xe0
[ 3.705161] drm_client_register+0x60/0xb0
[ 3.709269] drm_fbdev_dma_setup+0x94/0x148
Additionally, DMA memory is assumed to by contiguous in physical
address space, which is not guaranteed by vmalloc().
Resolve this by checking the module flag drm_leak_fbdev_smem when
DRM allocated the instance of struct fb_info. Fbdev-dma then only
sets smem_start only if required (via FBINFO_HIDE_SMEM_START). Also
guarantee that the framebuffer is not located in vmalloc address
space.
Vendor | Product | Version | CPE |
---|---|---|---|
linux | linux_kernel | * | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
[
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/gpu/drm/drm_fb_helper.c",
"drivers/gpu/drm/drm_fbdev_dma.c"
],
"versions": [
{
"version": "a51c7663f144",
"lessThan": "f29fcfbf6067",
"status": "affected",
"versionType": "git"
},
{
"version": "a51c7663f144",
"lessThan": "00702cfa8432",
"status": "affected",
"versionType": "git"
},
{
"version": "a51c7663f144",
"lessThan": "d92a7580392a",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/gpu/drm/drm_fb_helper.c",
"drivers/gpu/drm/drm_fbdev_dma.c"
],
"versions": [
{
"version": "6.4",
"status": "affected"
},
{
"version": "0",
"lessThan": "6.4",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.6.37",
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.9.8",
"lessThanOrEqual": "6.9.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.10",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
]