{"id":"CVE-2026-64280","state":"PUBLISHED","title":"fpga: dfl-afu: validate DMA mapping length in afu_dma_map_region()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nfpga: dfl-afu: validate DMA mapping length in afu_dma_map_region()\n\nafu_ioctl_dma_map() accepts a 64-bit length from userspace via\nDFL_FPGA_PORT_DMA_MAP ioctl without an upper bound check. The value\nis passed to afu_dma_pin_pages() where npages is derived as\nlength >> PAGE_SHIFT and passed to pin_user_pages_fast() which takes\nint nr_pages, causing implicit truncation if length is very large.\n\nValidate map.length at the ioctl entry point before calling\nafu_dma_map_region(), rejecting values whose page count exceeds\nINT_MAX.","publishedAt":"2026-07-25T08:49:23.753Z","updatedAt":"2026-08-23T12:45:39.157Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"5352d488ce4ae5e8c68c080ad4c3a5f084ad5fbc","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"d7e787eee2ea619b6dbb98890472ee73daf2e7fd","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"a6a3884ff500f04f3088d6d09eec803cd35331a2","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"16381bda90b261a656ded0568630c1b857b2ebc8","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"b50e6cd2395cde615f59b624819998d28c0668d6","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"59070040fd12e0b78d7b4d341d9f9a183237c5ff","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"fb2c0eab51ae5b02d2bae7d67c2cfbec39b57231","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"fc3b071a7c8dc0f5d56defddf6e6fd5aaa3e1e27","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/fpga/dfl-afu-main.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.19","versionType":"semver"},{"version":"5.10.266","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.217","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.184","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.148","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.101","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.39","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.4","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/fpga/dfl-afu-main.c"]}],"references":["https://git.kernel.org/stable/c/5352d488ce4ae5e8c68c080ad4c3a5f084ad5fbc","https://git.kernel.org/stable/c/d7e787eee2ea619b6dbb98890472ee73daf2e7fd","https://git.kernel.org/stable/c/a6a3884ff500f04f3088d6d09eec803cd35331a2","https://git.kernel.org/stable/c/16381bda90b261a656ded0568630c1b857b2ebc8","https://git.kernel.org/stable/c/b50e6cd2395cde615f59b624819998d28c0668d6","https://git.kernel.org/stable/c/59070040fd12e0b78d7b4d341d9f9a183237c5ff","https://git.kernel.org/stable/c/fb2c0eab51ae5b02d2bae7d67c2cfbec39b57231","https://git.kernel.org/stable/c/fc3b071a7c8dc0f5d56defddf6e6fd5aaa3e1e27"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/64xxx/CVE-2026-64280.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64280","state":"PUBLISHED","datePublished":"2026-07-25T08:49:23.753Z","dateUpdated":"2026-08-23T12:45:39.157Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T15:36:31.777Z"},"containers":{"cna":{"title":"fpga: dfl-afu: validate DMA mapping length in afu_dma_map_region()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nfpga: dfl-afu: validate DMA mapping length in afu_dma_map_region()\n\nafu_ioctl_dma_map() accepts a 64-bit length from userspace via\nDFL_FPGA_PORT_DMA_MAP ioctl without an upper bound check. The value\nis passed to afu_dma_pin_pages() where npages is derived as\nlength >> PAGE_SHIFT and passed to pin_user_pages_fast() which takes\nint nr_pages, causing implicit truncation if length is very large.\n\nValidate map.length at the ioctl entry point before calling\nafu_dma_map_region(), rejecting values whose page count exceeds\nINT_MAX."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"5352d488ce4ae5e8c68c080ad4c3a5f084ad5fbc","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"d7e787eee2ea619b6dbb98890472ee73daf2e7fd","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"a6a3884ff500f04f3088d6d09eec803cd35331a2","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"16381bda90b261a656ded0568630c1b857b2ebc8","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"b50e6cd2395cde615f59b624819998d28c0668d6","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"59070040fd12e0b78d7b4d341d9f9a183237c5ff","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"fb2c0eab51ae5b02d2bae7d67c2cfbec39b57231","versionType":"git"},{"version":"fa8dda1edef9ebc3af467c644c5533ac97171e12","status":"affected","lessThan":"fc3b071a7c8dc0f5d56defddf6e6fd5aaa3e1e27","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/fpga/dfl-afu-main.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.19","versionType":"semver"},{"version":"5.10.266","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.217","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.184","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.148","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.101","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.39","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.4","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/fpga/dfl-afu-main.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/5352d488ce4ae5e8c68c080ad4c3a5f084ad5fbc"},{"url":"https://git.kernel.org/stable/c/d7e787eee2ea619b6dbb98890472ee73daf2e7fd"},{"url":"https://git.kernel.org/stable/c/a6a3884ff500f04f3088d6d09eec803cd35331a2"},{"url":"https://git.kernel.org/stable/c/16381bda90b261a656ded0568630c1b857b2ebc8"},{"url":"https://git.kernel.org/stable/c/b50e6cd2395cde615f59b624819998d28c0668d6"},{"url":"https://git.kernel.org/stable/c/59070040fd12e0b78d7b4d341d9f9a183237c5ff"},{"url":"https://git.kernel.org/stable/c/fb2c0eab51ae5b02d2bae7d67c2cfbec39b57231"},{"url":"https://git.kernel.org/stable/c/fc3b071a7c8dc0f5d56defddf6e6fd5aaa3e1e27"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable path is reached locally through DFL_FPGA_PORT_DMA_MAP on a /dev/dfl-port.* character device.\nAC:L - A page-aligned length whose page count wraps to zero or a small positive integer deterministically triggers the mismatch; no race or condition outside the attacker’s control is required.\nPR:L - The ioctl contains no capability or namespace privilege check, so any unprivileged user granted access to the port device can trigger it.\nUI:N - The attacker independently opens the device and submits the malicious ioctl without any victim action.\nS:C - The oversized DMA mapping can cross the IOMMU-enforced boundary between the assigned user buffer and host physical memory, affecting kernel and other-user resources.\nC:H - A small positive page-count wrap can create an enormous DMA-readable mapping after pinning only a few pages, exposing host memory beyond the authorized buffer; teardown also performs unbounded out-of-bounds pointer reads.\nI:H - The mapping is DMA_BIDIRECTIONAL, permitting writes beyond the pinned buffer, while the oversized unpin operation can corrupt unrelated page reference counts through out-of-bounds page pointers.\nA:H - A zero page-count wrap causes a deterministic pages[0] dereference from a zero-sized allocation, while other wrapped counts can produce an unbounded unpin traversal and kernel crash."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-23T12:45:39.157Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"5.10.266"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"5.15.217"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"6.1.184"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"6.6.148"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"6.12.101"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"6.18.39"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"7.1.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}