{"id":"CVE-2026-98166","revision":"dcf909965de94127859354e0e69baed9","records":[{"revision":"dcf909965de94127859354e0e69baed9","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-98166","aliases":[],"title":"drm/ttm: fix swapped-out resources never leaving their bulk_move range","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/ttm: fix swapped-out resources never leaving their bulk_move range\n\nttm_tt_swapout() returns the number of pages swapped out on success and\na negative error code on failure; for a populated ttm it never returns\nzero. Commit b2ed01e7ad3d (\"drm/ttm: Fix ttm_bo_swapout() infinite LRU\nwalk on swapout failure\") moved the bulk_move bookkeeping in\nttm_bo_swapout_cb() under \"if (!ret)\", so the\nttm_resource_del_bulk_move_unevictable() / ttm_resource_move_to_lru_tail()\npair is now skipped on every successful swapout. The equivalent change\nfor the shrinker in commit 1d59f36e95f7 (\"drm/ttm: Fix ttm_bo_shrink()\ninfinite LRU walk on backup failure\") tests \"lret > 0\", which is what\nwas intended here as well.\n\nBefore b2ed01e7ad3d the resource was taken off the bulk_move before the\nswapout; since then a swapped-out resource stays inside its BO's\nbulk_move range (and on the manager LRU) although it is unevictable.\nWhen it is later freed or the BO leaves the bulk_move\n(ttm_resource_free(), ttm_bo_set_bulk_move() via amdgpu_vm_bo_del()),\nttm_resource_del_bulk_move() skips it because of its\n!ttm_resource_unevictable() guard, so a range endpoint in pos->first /\npos->last is left pointing at freed memory. The next\nttm_lru_bulk_move_tail() or ttm_resource_add_bulk_move() on that cursor\nis a use-after-free, seen as the resv WARN in ttm_lru_bulk_move_add(),\n\"list_del corruption\" in ttm_resource_move_to_lru_tail() or a NULL\ndereference in ttm_resource_manager_next() -- minutes to hours after a\nhibernation, or at process exit / reboot following one. Samuel\nAinsworth's analysis of drm/amd issue 5387 (see Link) identified the\ndangling cursor; the missing removal at swapout time is the reason it\ndangles.\n\nTesting the condition for success restores the removal. On an AMD\nPhoenix APU (ASUS UM3406GA, gfx1103) running suspend-then-hibernate on\na 7.0.y stable kernel carrying the backport (Ubuntu 7.0.0-31) the bug\ncrashed 5 of 18 hibernation cycles; a function profile of one\nhibernation showed 336 ttm_tt_swapout() calls and zero\nttm_resource_del_bulk_move_unevictable() calls. With this change the\nremoval happens for every swapped-out resource and 12 further cycles\nwere clean.","state":0,"publishedAt":"2026-10-06T08:44:11.927+00:00","modifiedAt":"2026-10-19T09:14:57.782+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/gpu/drm/ttm/ttm_bo.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"b2ed01e7ad3de80333e9b962a44024b094bc0b2b\",\n                            \"lessThan\": \"1169fe8c11ca45e3f91d59a73eb271d0ca8a7fb0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"b2ed01e7ad3de80333e9b962a44024b094bc0b2b\",\n                            \"lessThan\": \"3db7d7d583419f7b1f2e141e36418802dbb25cf8\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"060f8f3020516d71bc4d6159d4d0beef85606a74\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0124a09e3e5f5f6080efe9663b27af27933f8382\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"6.18.57\",\n                            \"lessThan\": \"6.19\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.0.10\",\n                            \"lessThan\": \"7.1\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\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/gpu/drm/ttm/ttm_bo.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"7.1\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"7.1\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.8\",\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/1169fe8c11ca45e3f91d59a73eb271d0ca8a7fb0","https://git.kernel.org/stable/c/3db7d7d583419f7b1f2e141e36418802dbb25cf8"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98166","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98166","identifiers":["CVE-2026-98166"]},"retained":false,"historicalAffected":[]}],"coverage":[]}