{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-64590", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.798Z", "datePublished": "2026-08-06T07:13:47.888Z", "dateUpdated": "2026-08-06T07:13:47.888Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-06T07:13:47.888Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndma-buf/udmabuf: skip redundant cpu sync to fix cacheline EEXIST warning\n\nWhen CONFIG_DMA_API_DEBUG_SG is enabled, importing a udmabuf into a DRM\ndriver (e.g. amdgpu for video playback in GNOME Videos / Showtime)\ntriggers a spurious warning:\n\n DMA-API: amdgpu 0000:03:00.0: cacheline tracking EEXIST, \\\n overlapping mappings aren't supported\n WARNING: kernel/dma/debug.c:619 at add_dma_entry+0x473/0x5f0\n\nThe call chain is:\n\n amdgpu_cs_ioctl\n -> amdgpu_ttm_backend_bind\n -> dma_buf_map_attachment\n -> [udmabuf] map_udmabuf -> get_sg_table\n -> dma_map_sgtable(dev, sg, direction, 0) // attrs=0\n -> debug_dma_map_sg -> add_dma_entry -> EEXIST\n\nThis happens because udmabuf builds a per-page scatter-gather list via\nsg_set_folio(). When begin_cpu_udmabuf() has already created an sg\ntable mapped for the misc device, and an importer such as amdgpu maps\nthe same pages for its own device via map_udmabuf(), the DMA debug\ninfrastructure sees two active mappings whose physical addresses share\ncacheline boundaries and warns about the overlap.\n\nThe DMA_ATTR_SKIP_CPU_SYNC flag suppresses this check in\nadd_dma_entry() because it signals that no CPU cache maintenance is\nperformed at map/unmap time, making the cacheline overlap harmless.\n\nAll other major dma-buf exporters already pass this flag:\n - drm_gem_map_dma_buf() passes DMA_ATTR_SKIP_CPU_SYNC\n - amdgpu_dma_buf_map() passes DMA_ATTR_SKIP_CPU_SYNC\n\nThe CPU sync at map/unmap time is also redundant for udmabuf:\nbegin_cpu_udmabuf() and end_cpu_udmabuf() already perform explicit\ncache synchronization via dma_sync_sgtable_for_cpu/device() when CPU\naccess is requested through the dma-buf interface.\n\nPass DMA_ATTR_SKIP_CPU_SYNC to dma_map_sgtable() and\ndma_unmap_sgtable() in udmabuf to suppress the spurious warning and\nskip the redundant sync."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/dma-buf/udmabuf.c"], "versions": [{"version": "284562e1f34874e267d4f499362c3816f8f6bc3f", "lessThan": "0db56e7eae932f8e2f3eb44ad1a63633d8f504f8", "status": "affected", "versionType": "git"}, {"version": "284562e1f34874e267d4f499362c3816f8f6bc3f", "lessThan": "d6552f5cff795d60e629f37513ecf23d88fd2f82", "status": "affected", "versionType": "git"}, {"version": "284562e1f34874e267d4f499362c3816f8f6bc3f", "lessThan": "34696563461c9a23177feb6d8aff43f4c0510278", "status": "affected", "versionType": "git"}, {"version": "284562e1f34874e267d4f499362c3816f8f6bc3f", "lessThan": "0449a6583c0ee76778d314e4e82f166fc97fa9d8", "status": "affected", "versionType": "git"}, {"version": "284562e1f34874e267d4f499362c3816f8f6bc3f", "lessThan": "504e2b4ab97a51d56d966cd36d0997ad30b65b2d", "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/dma-buf/udmabuf.c"], "versions": [{"version": "5.6", "status": "affected"}, {"version": "0", "lessThan": "5.6", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.148", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.96", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.39", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.4", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2-rc1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "6.6.148"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "6.12.96"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "6.18.39"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "7.1.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "7.2-rc1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/0db56e7eae932f8e2f3eb44ad1a63633d8f504f8"}, {"url": "https://git.kernel.org/stable/c/d6552f5cff795d60e629f37513ecf23d88fd2f82"}, {"url": "https://git.kernel.org/stable/c/34696563461c9a23177feb6d8aff43f4c0510278"}, {"url": "https://git.kernel.org/stable/c/0449a6583c0ee76778d314e4e82f166fc97fa9d8"}, {"url": "https://git.kernel.org/stable/c/504e2b4ab97a51d56d966cd36d0997ad30b65b2d"}], "title": "dma-buf/udmabuf: skip redundant cpu sync to fix cacheline EEXIST warning", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

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{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[284562e1f34874e267d4f499362c3816f8f6bc3f,0db56e7eae932f8e2f3eb44ad1a63633d8f504f8)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[284562e1f34874e267d4f499362c3816f8f6bc3f,d6552f5cff795d60e629f37513ecf23d88fd2f82)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[284562e1f34874e267d4f499362c3816f8f6bc3f,34696563461c9a23177feb6d8aff43f4c0510278)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[284562e1f34874e267d4f499362c3816f8f6bc3f,0449a6583c0ee76778d314e4e82f166fc97fa9d8)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[284562e1f34874e267d4f499362c3816f8f6bc3f,504e2b4ab97a51d56d966cd36d0997ad30b65b2d)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "5.6"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,5.6)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.148,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.96,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.39,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.4,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-08-06T09:15:02.758985+00:00", "updated": "2026-08-06T09:30:02.868918+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-532"]}