{"id":"CVE-2026-46114","revision":"272a8c9d348c4c578ad8d3aafcfb6800","records":[{"revision":"272a8c9d348c4c578ad8d3aafcfb6800","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-46114","aliases":[],"title":"RDMA/rxe: Reject non-8-byte ATOMIC_WRITE payloads","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rxe: Reject non-8-byte ATOMIC_WRITE payloads\n\natomic_write_reply() at drivers/infiniband/sw/rxe/rxe_resp.c\nunconditionally dereferences 8 bytes at payload_addr(pkt):\n\n    value = *(u64 *)payload_addr(pkt);\n\ncheck_rkey() previously accepted an ATOMIC_WRITE request with pktlen ==\nresid == 0 because the length validation only compared pktlen against\nresid. A remote initiator that sets the RETH length to 0 therefore reaches\natomic_write_reply() with a zero-byte logical payload, and the responder\nreads sizeof(u64) bytes from past the logical end of the packet into\nskb->head tailroom, then writes those 8 bytes into the attacker's MR via\nrxe_mr_do_atomic_write(). That is a remote disclosure of 4 bytes of kernel\ntailroom per probe (the other 4 bytes are the packet's own trailing ICRC).\n\nIBA oA19-28 defines ATOMIC_WRITE as exactly 8 bytes. Anything else is\nprotocol-invalid. Hoist a strict length check into check_rkey() so the\nresponder never reaches the unchecked dereference, and keep the existing\nWRITE-family length logic for the normal RDMA WRITE path.\n\nReproduced on mainline with an unmodified rxe driver: a sustained\nzero-length ATOMIC_WRITE probe repeatedly leaks adjacent skb head-buffer\nbytes into the attacker's MR, including recognisable kernel strings and\npartial kernel-direct-map pointer words.  With this patch applied the\nresponder rejects the PDU and the MR stays all-zero.","state":0,"publishedAt":"2026-05-28T09:35:24.638+00:00","modifiedAt":"2026-10-19T19:26:44.201+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                        \"drivers/infiniband/sw/rxe/rxe_resp.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"034e285f8b99062a0cf29112e1232154a6a44aa5\",\n                            \"lessThan\": \"539cabb7b2d8ba70f55bba91db55faef11c2a6d7\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"034e285f8b99062a0cf29112e1232154a6a44aa5\",\n                            \"lessThan\": \"d415fce3fcde6d7aeea6c25362a395b905811452\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"034e285f8b99062a0cf29112e1232154a6a44aa5\",\n                            \"lessThan\": \"105bf79a23b85cf3a761d18a4f3e10ce88526bc1\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"034e285f8b99062a0cf29112e1232154a6a44aa5\",\n                            \"lessThan\": \"7ec1ed4747f5f99f8b797bb438c5efd36079fad5\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"034e285f8b99062a0cf29112e1232154a6a44aa5\",\n                            \"lessThan\": \"1114c87aa6f195cf07da55a27b2122ae26557b26\",\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                        \"drivers/infiniband/sw/rxe/rxe_resp.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.2\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.2\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.140\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.88\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.30\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.0.7\",\n                            \"lessThanOrEqual\": \"7.0.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","score":7.5,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/539cabb7b2d8ba70f55bba91db55faef11c2a6d7","https://git.kernel.org/stable/c/d415fce3fcde6d7aeea6c25362a395b905811452","https://git.kernel.org/stable/c/105bf79a23b85cf3a761d18a4f3e10ce88526bc1","https://git.kernel.org/stable/c/7ec1ed4747f5f99f8b797bb438c5efd36079fad5","https://git.kernel.org/stable/c/1114c87aa6f195cf07da55a27b2122ae26557b26"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-46114","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-46114","identifiers":["CVE-2026-46114"]},"retained":false,"historicalAffected":[]}],"coverage":[]}