{"id":"CVE-2026-90051","revision":"0f3ebbfd5ee94cd3bc546d8a45d45100","records":[{"revision":"0f3ebbfd5ee94cd3bc546d8a45d45100","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-90051","aliases":[],"title":"tcp: reject non zerocopy devmem tx","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: reject non zerocopy devmem tx\n\nDevmem tcp tx doesn't work without zero-copy, however it's not currently\nenforced if NETIF_F_SG isn't present. In this case, tcp_sendmsg_locked()\nwill try the copy path and try to copy data from an iovec which consists\nof offsets into the dma-buf and would normally fail. Moreover,\nd9c56501c72fd (\"net: tcp: block mixing readable and unreadable frags\")\nrelies on that and assumes that the devmem binding is present IFF we're\nusing the zero-copy path, which can be used to mix net-iov and pages in\na single skb, and break invariants. Let's reject devmem tx without\nzero-copy.\n\nNote, the parameter check the patch is modifying is too loose, we can\ncreate an io_uring request with dmabuf_id and all ZC flags, but which\nwon't have the binding. We replace it with stricter validation.","state":0,"publishedAt":"2026-09-17T16:05:37.62+00:00","modifiedAt":"2026-10-19T08:57:09.627+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/ipv4/tcp.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"bd61848900bff597764238f3a8ec67c815cd316e\",\n                            \"lessThan\": \"2151b2bcf6fcec52665f606eed20da068447f0b7\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"bd61848900bff597764238f3a8ec67c815cd316e\",\n                            \"lessThan\": \"b04326c7927af7048fd4e730f5770cca350d0a60\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"bd61848900bff597764238f3a8ec67c815cd316e\",\n                            \"lessThan\": \"125755776bc6d4dd53eaf551c87e3d460625d638\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/ipv4/tcp.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.16\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.16\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.52\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.6\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/2151b2bcf6fcec52665f606eed20da068447f0b7","https://git.kernel.org/stable/c/b04326c7927af7048fd4e730f5770cca350d0a60","https://git.kernel.org/stable/c/125755776bc6d4dd53eaf551c87e3d460625d638"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-90051","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-90051","identifiers":["CVE-2026-90051"]},"retained":false,"historicalAffected":[]}],"coverage":[]}