CVE-2021-47305

In the Linux kernel, the following vulnerability has been resolved: dma-buf/sync_file: Don't leak fences on merge failure Each add_fence() call does a dma_fence_get() on the relevant fence. In the error path, we weren't calling dma_fence_put() so all those fences got leaked. Also, in the krealloc_array failure case, we weren't freeing the fences array. Instead, ensure that i and fences are always zero-initialized and dma_fence_put() all the fences and kfree(fences) on every error path.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/0d514185ae792d3a1903c8e1a83899aa996705ce	Patch
https://git.kernel.org/stable/c/19edcd97727aae9362444a859a24d99a8730cb27	Patch
https://git.kernel.org/stable/c/19f51c2529339280d2c8c6427cd3e21ddf1ac3f8	Patch
https://git.kernel.org/stable/c/41f45e91c92c8480242ea448d54e28c753b13902	Patch
https://git.kernel.org/stable/c/e0355a0ad31a1d677b2a4514206de4902bd550e8	Patch
https://git.kernel.org/stable/c/ffe000217c5068c5da07ccb1c0f8cce7ad767435	Patch
https://git.kernel.org/stable/c/0d514185ae792d3a1903c8e1a83899aa996705ce	Patch
https://git.kernel.org/stable/c/19edcd97727aae9362444a859a24d99a8730cb27	Patch
https://git.kernel.org/stable/c/19f51c2529339280d2c8c6427cd3e21ddf1ac3f8	Patch
https://git.kernel.org/stable/c/41f45e91c92c8480242ea448d54e28c753b13902	Patch
https://git.kernel.org/stable/c/e0355a0ad31a1d677b2a4514206de4902bd550e8	Patch
https://git.kernel.org/stable/c/ffe000217c5068c5da07ccb1c0f8cce7ad767435	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:5.14:rc1::::::

History

No history.

Information

Published : 2024-05-21 15:15

Updated : 2025-05-12 20:00

NVD link : CVE-2021-47305

Mitre link : CVE-2021-47305

CVE.ORG link : CVE-2021-47305

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-617

Reachable Assertion

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In\nthe error path, we weren't calling dma_fence_put() so all those fences\ngot leaked. Also, in the krealloc_array failure case, we weren't\nfreeing the fences array. Instead, ensure that i and fences are always\nzero-initialized and dma_fence_put() all the fences and kfree(fences) on\nevery error path."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: dma-buf/sync_file: no filtrar barreras en caso de falla de fusi\u00f3n. Cada llamada a add_fence() realiza un dma_fence_get() en la barrera relevante. En la ruta del error, no est\u00e1bamos llamando a dma_fence_put() por lo que se filtraron todas esas barreras. Adem\u00e1s, en el caso de falla de krealloc_array, no est\u00e1bamos liberando la matriz de vallas. En su lugar, aseg\u00farese de que i y las vallas est\u00e9n siempre inicializadas en cero y dma_fence_put() todas las vallas y kfree(fences) en cada ruta de error."}], "lastModified": "2025-05-12T20:00:28.990", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A5E7A8DD-98C2-4C78-A535-5E3305CABAB7", "versionEndExcluding": "4.14.241", "versionStartIncluding": "4.9"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D1C5B0E1-06E7-4615-AA17-02585202D86E", "versionEndExcluding": "4.19.199", "versionStartIncluding": "4.15"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "3EF7BA79-262D-4A55-A0A1-E0D0BCA7C320", "versionEndExcluding": "5.4.135", "versionStartIncluding": "4.20"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "08E2D438-D50E-43C5-AF10-D62FE49B5815", "versionEndExcluding": "5.10.53", "versionStartIncluding": "5.5"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "808DF8D9-4913-4CC7-B91F-B4146556B7ED", "versionEndExcluding": "5.13.5", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.14:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "71268287-21A8-4488-AA4F-23C473153131"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}