{"id":"CVE-2026-64268","summary":"RDMA/siw: bound Read Response placement to the RREAD length","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/siw: bound Read Response placement to the RREAD length\n\nIn drivers/infiniband/sw/siw/siw_qp_rx.c, siw_proc_rresp() places each\ninbound Read Response DDP segment at sge-\u003eladdr + wqe-\u003eprocessed and then\naccumulates wqe-\u003eprocessed, but it never checks the running total against\nthe sink buffer length on continuation segments. siw_check_sge() resolves\nand validates the sink memory only on the first fragment (the if (!*mem)\nbranch), and siw_rresp_check_ntoh() compares the cumulative length against\nwqe-\u003ebytes only on the final segment (the !frx-\u003emore_ddp_segs guard).\n\nA connected siw peer that answers an outstanding RREAD with Read Response\nsegments that keep the DDP Last flag clear, carrying more total payload\nthan the RREAD requested, drives wqe-\u003eprocessed past the validated sink\nbuffer; the next siw_rx_data() call writes out of bounds at\nsge-\u003eladdr + wqe-\u003eprocessed. siw runs iWARP over ordinary routable TCP,\nso the peer is the remote end of an established RDMA connection and needs\nno local privilege.\n\nBound every segment before placement, exactly as siw_proc_send() and\nsiw_proc_write() already do for their tagged and untagged paths, and\nterminate the connection with a base-or-bounds DDP error when the\nRead Response would overrun the sink buffer.\n\nThis is the second receive-path length fix for this file. A separate\nchange rejects an MPA FPDU length that underflows the per-fragment\nremainder in the header decode; that guard does not cover this case,\nbecause here each individual segment length is self-consistent and only\nthe accumulated placement offset overruns the buffer.","modified":"2026-09-03T10:56:52.904272828Z","published":"2026-07-25T08:49:16.336Z","related":["ALSA-2026:63013","ALSA-2026:63014","openSUSE-SU-2026:11476-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64268.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/3ef7e052cbd05a8b13a51a07b185a39ec93ee1cf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/423a78ff7928c2601013f73ec6d896f5597d0df5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/595e6537ad1a210da32cbb9a7f91aa73090915ba"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6bc89f34a4597f9f6d41f7a60c67a3153bfe8851"},{"type":"WEB","url":"https://git.kernel.org/stable/c/75c93cd3c421890f49ea93f0b978b9b7bb10e5e3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7d29f7e9dbd844cae4d3e559cf78324b9642fd6b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a31b6d18ded3cc32d9ee85a6ff0726d4274887b2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b2e26c955f8dd7e8d3f16c858db05245ea4fa817"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64268.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64268"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"8b6a361b8c482f22ac99c3273285ff16b23fba91"},{"fixed":"a31b6d18ded3cc32d9ee85a6ff0726d4274887b2"},{"fixed":"595e6537ad1a210da32cbb9a7f91aa73090915ba"},{"fixed":"3ef7e052cbd05a8b13a51a07b185a39ec93ee1cf"},{"fixed":"b2e26c955f8dd7e8d3f16c858db05245ea4fa817"},{"fixed":"6bc89f34a4597f9f6d41f7a60c67a3153bfe8851"},{"fixed":"423a78ff7928c2601013f73ec6d896f5597d0df5"},{"fixed":"75c93cd3c421890f49ea93f0b978b9b7bb10e5e3"},{"fixed":"7d29f7e9dbd844cae4d3e559cf78324b9642fd6b"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-64268.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.3.0"},{"fixed":"5.10.261"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.212"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.178"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.145"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.96"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.39"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-64268.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}