{"id":"CVE-2026-99166","revision":"748ca62e1c3045ea8d5fc3ab9dcf0bce","records":[{"revision":"748ca62e1c3045ea8d5fc3ab9dcf0bce","observedAt":"2026-10-30T13:45:33.454+00:00","statement":{"source":"cve-program","id":"CVE-2026-99166","aliases":[],"title":"net: rds: fix uninitialized trans dereference in CM event handler","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: rds: fix uninitialized trans dereference in CM event handler\n\nrds_rdma_cm_event_handler_cmn() assigns trans only when the RDMA\ndevice is an InfiniBand CA (RDMA_NODE_IB_CA).  On any other device\ntype, e.g. an iWARP RNIC such as siw, trans stays uninitialized, but\nthe event switch dereferences it: unconditionally in the\nRDMA_CM_EVENT_CONNECT_REQUEST case via trans->cm_handle_connect(),\nand (with a connection context) in the ROUTE_RESOLVED and\nESTABLISHED cases.\n\nAn RDS listener on an iWARP device therefore crashes the kernel as\nsoon as a connect request arrives: with CONFIG_INIT_STACK_ALL_ZERO\nthe wild load becomes a NULL dereference at offset 0xa0\n(&trans->cm_handle_connect) in the iw_cm_wq workqueue.\n\nGCC masks the bug in default builds by folding the uninitialized\nload into &rds_ib_transport; Clang-built kernels take the real\nuninitialized path and oops.\n\nThe active side can land on a non-IB device too: the id that\nrds_ib_conn_path_connect() creates is not restricted to a node type,\nso rdma_resolve_addr() binds it to whichever device serves the local\naddress, and an iWARP RNIC on the same netdev qualifies.  The crash\nthere is different: resolving a route on an iWARP id never fills in\ncm_id->route.path_rec, and the ROUTE_RESOLVED case writes\npath_rec[0].sl before it calls into the transport.\n\nThe iWARP transport was dropped long ago and IB is the only\ntransport left, so make that explicit: initialize trans to\n&rds_ib_transport at declaration, drop the conditional assignment,\nreject a connect request that arrives on a non-IB device, and drop a\nconnection whose address resolved to one instead of resolving a\nroute on it.  The rejection is limited to RDMA_CM_EVENT_CONNECT_REQUEST\non purpose: a non-zero return from the handler makes rdma_cm destroy\nthe id the event was delivered on, which is right for the request's\nfreshly created id but would free a connection id that RDS still owns\nfor any other event.  On the active side the id stays ic->i_cm_id and\nthe connection's shutdown destroys it, so that case returns 0.\n\n[achender: reject only on RDMA_CM_EVENT_CONNECT_REQUEST instead of\n bailing out for every event on a non-IB device, so that rdma_cm does\n not destroy connection ids RDS still tracks; drop a connection whose\n address resolved to a non-IB device before a route is resolved on it;\n changelog adjusted]","state":0,"publishedAt":"2026-10-28T10:35:18.05+00:00","modifiedAt":"2026-10-30T12:42:32.571+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/rds/rdma_transport.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"dcdede0406d30e14a6ed727dce69dfac0518371d\",\n                            \"lessThan\": \"0d15e853aa88da5375edd32b39d08a048b64a1c5\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"dcdede0406d30e14a6ed727dce69dfac0518371d\",\n                            \"lessThan\": \"8c77774535c3d6162929521a6fa11e3db086fa32\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"dcdede0406d30e14a6ed727dce69dfac0518371d\",\n                            \"lessThan\": \"8973f70cb068012d83cff1cfa3f45ef94ab02267\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"dcdede0406d30e14a6ed727dce69dfac0518371d\",\n                            \"lessThan\": \"a2fde862b98db8908e2ebaffbb35a75a0e9d5b33\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"dcdede0406d30e14a6ed727dce69dfac0518371d\",\n                            \"lessThan\": \"074bb7cdc3e26afa698888ba56fc1df0e3f24650\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"dcdede0406d30e14a6ed727dce69dfac0518371d\",\n                            \"lessThan\": \"5f23e4e3a31dacfd82a8f56be253adc0910ee84f\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"dcdede0406d30e14a6ed727dce69dfac0518371d\",\n                            \"lessThan\": \"ca14c289ed9ffed6cc64290d039e923e5720a8bf\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"dcdede0406d30e14a6ed727dce69dfac0518371d\",\n                            \"lessThan\": \"492ba6ac1b1ffb8a06ff52db0825c1af2cdb28c8\",\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/rds/rdma_transport.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4.6\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"4.6\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.273\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.224\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.191\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.161\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.115\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.59\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.13\",\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":[],"references":["https://git.kernel.org/stable/c/0d15e853aa88da5375edd32b39d08a048b64a1c5","https://git.kernel.org/stable/c/8c77774535c3d6162929521a6fa11e3db086fa32","https://git.kernel.org/stable/c/8973f70cb068012d83cff1cfa3f45ef94ab02267","https://git.kernel.org/stable/c/a2fde862b98db8908e2ebaffbb35a75a0e9d5b33","https://git.kernel.org/stable/c/074bb7cdc3e26afa698888ba56fc1df0e3f24650","https://git.kernel.org/stable/c/5f23e4e3a31dacfd82a8f56be253adc0910ee84f","https://git.kernel.org/stable/c/ca14c289ed9ffed6cc64290d039e923e5720a8bf","https://git.kernel.org/stable/c/492ba6ac1b1ffb8a06ff52db0825c1af2cdb28c8"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-99166","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-99166","identifiers":["CVE-2026-99166"]},"retained":false,"historicalAffected":[]}],"coverage":[]}