CVE-2021-47477

comedi: dt9812: fix DMA buffers on stack

HIGH
7.8
CVSS Score
Published: May 22, 2024 at 08:19 AM UTC
Updated: June 17, 2026 at 04:17 AM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
HIGH7.8
Exploit prediction
EPSS 0.7%
SSVC
No known exploit

Description

In the Linux kernel, the following vulnerability has been resolved: comedi: dt9812: fix DMA buffers on stack USB transfer buffers are typically mapped for DMA and must not be allocated on the stack or transfers will fail. Allocate proper transfer buffers in the various command helpers and return an error on short transfers instead of acting on random stack data. Note that this also fixes a stack info leak on systems where DMA is not used as 32 bytes are always sent to the device regardless of how short the command is.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

2.6.29 ≤ v < 4.14.2552.6.29 ≤ v < 4.19.2172.6.29 ≤ v < 4.4.2922.6.29 ≤ v < 4.9.2902.6.29 ≤ v < 5.10.792.6.29 ≤ v < 5.14.182.6.29 ≤ v < 5.15.22.6.29 ≤ v < 5.162.6.29 ≤ v < 5.4.1594.10 ≤ v < 4.14.2554.15 ≤ v < 4.19.2174.20 ≤ v < 5.4.1594.5 ≤ v < 4.9.2905.11 ≤ v < 5.14.185.15 ≤ v < 5.15.25.5 ≤ v < 5.10.792.6.2963274cd7d38a3322d90b66a5bc976de1fb899051
Vendor states this is fixed in 20cebb8b620dc987e55ddc46801de986e081757e (fixed)
Vendor states this is fixed in 365a346cda82f51d835c49136a00a9df8a78c7f2 (fixed)
Vendor states this is fixed in 39ea61037ae78f14fa121228dd962ea3280eacf3 (fixed)
Vendor states this is fixed in 3ac273d154d634e2034508a14db82a95d7ad12ed (fixed)
Vendor states this is fixed in 3efb7af8ac437085b6c776e5b54830b149d86efe (fixed)
Vendor states this is fixed in 536de747bc48262225889a533db6650731ab25d3 (fixed)
Vendor states this is fixed in 786f5b03450454557ff858a8bead5d7c0cbf78d6 (fixed)
Vendor states this is fixed in 8a52bc480992c7c9da3ebfea456af731f50a4b97 (fixed)
Vendor states this is fixed in a6af69768d5cb4b2528946d53be5fa19ade37723 (fixed)
Vendor states this is fixed in 2.6.29 (unaffected)
Vendor states this is fixed in 4.14.255 (unaffected)
Vendor states this is fixed in 4.19.217 (unaffected)
Vendor states this is fixed in 4.4.292 (unaffected)
Vendor states this is fixed in 4.9.290 (unaffected)
Vendor states this is fixed in 5.10.79 (unaffected)
Vendor states this is fixed in 5.14.18 (unaffected)
Vendor states this is fixed in 5.15.2 (unaffected)
Vendor states this is fixed in 5.16 (unaffected)
Vendor states this is fixed in 5.4.159 (unaffected)

References (9)

Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/20cebb8b620dc987e55ddc46801de986e081757e
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/365a346cda82f51d835c49136a00a9df8a78c7f2
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/39ea61037ae78f14fa121228dd962ea3280eacf3
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/3ac273d154d634e2034508a14db82a95d7ad12ed
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/3efb7af8ac437085b6c776e5b54830b149d86efe
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/536de747bc48262225889a533db6650731ab25d3
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/786f5b03450454557ff858a8bead5d7c0cbf78d6
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/8a52bc480992c7c9da3ebfea456af731f50a4b97

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-787

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