{"id":"CVE-2026-98520","revision":null,"records":[{"revision":"233711223e39488a8dbd2b23ec9e13df","observedAt":"2026-10-24T16:17:04.479+00:00","statement":{"source":"cve-program","id":"CVE-2026-98520","aliases":[],"title":"drm/amdkfd: fix use-after-free and multi-container gap in kfd_dev_mapping","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdkfd: fix use-after-free and multi-container gap in kfd_dev_mapping\n\nkfd_dev_mapping caches the address_space of the first /dev/kfd opener\nso that the GPU reset path can call unmap_mapping_range() to zap all\nuserspace mappings of doorbell and MMIO ranges.  This design has two\nbugs that both manifest under SRIOV with multiple containers:\n\n1. Use-after-free / rwsem deadlock.  The cached pointer refers to an\n   inode owned by the first opener's container.  When that container\n   exits and its inode is released, kfd_dev_mapping becomes a dangling\n   pointer.  A subsequent GPU reset dereferences it inside\n   unmap_mapping_range(), which takes i_mmap_rwsem on the freed inode,\n   causing a hard hang observable as an uninterruptible rwsem wait.\n\n2. Multi-container gap.  Only the first opener's address_space is cached;\n   VMAs created by later openers live in a different address_space and\n   are never reached by unmap_mapping_range().  After a GPU reset those\n   stale mappings keep doorbell and MMIO pages accessible to guest\n   userspace with no GPU behind them, risking PCIe transaction timeouts\n   and NMI panics.\n\nFix both bugs with the same approach used by DRM core (drm_drv.c):\ncreate a private pseudo-filesystem at module init time and allocate one\nanonymous inode from it.  In kfd_open() redirect every opener's\nfile->f_mapping to that inode's address_space.  The inode is\nmodule-owned, lives exactly as long as the amdgpu module, and collects\nVMAs from all openers in one address_space.  A single\nunmap_mapping_range() call in the reset path then correctly reaches\nevery container's mappings with no dangling pointer risk.\n\nThe hang manifests as an NMI backtrace on the GPU reset workqueue stuck\nspinning in rwsem_down_read_slowpath() with a corrupted i_mmap_rwsem:\n\n  Workqueue: amdgpu-reset-dev xgpu_ai_mailbox_flr_work [amdgpu]\n  Call Trace:\n   <TASK>\n   kvm_wait+0x1f/0x40\n   __pv_queued_spin_lock_slowpath+0x31d/0x3a0\n   _raw_spin_lock_irq+0x51/0x80\n   rwsem_down_read_slowpath+0xb3/0x550\n   down_read+0x48/0xd0\n   unmap_mapping_range+0x71/0x140\n   kfd_dev_unmap_mapping_range+0x5b/0x140 [amdgpu]\n   amdgpu_amdkfd_clear_kfd_mapping+0xd8/0x190 [amdgpu]\n   amdgpu_device_gpu_recover+0x232/0x450 [amdgpu]\n   xgpu_ai_mailbox_flr_work+0xb5/0xc0 [amdgpu]\n   process_one_work+0x18e/0x3e0\n   worker_thread+0x2e3/0x420\n   kthread+0x10a/0x230\n\n(cherry picked from commit 1128b4a52de1572e87431de837fd9850cb99542c)","state":0,"publishedAt":"2026-10-18T15:17:38.113+00:00","modifiedAt":"2026-10-24T14:09:16.913+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/amd/amdkfd/kfd_chardev.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"70cadefcc6160c575b04f763ada34c20e868d577\",\n                            \"lessThan\": \"02b74891624e09a5512c6d84f267d01fcc306a3b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"70cadefcc6160c575b04f763ada34c20e868d577\",\n                            \"lessThan\": \"c3a31087b1c8df679b653c1a09d9abe5ff7ec8ef\",\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/gpu/drm/amd/amdkfd/kfd_chardev.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"7.2\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"7.2\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.9\",\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/02b74891624e09a5512c6d84f267d01fcc306a3b","https://git.kernel.org/stable/c/c3a31087b1c8df679b653c1a09d9abe5ff7ec8ef"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98520","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98520","identifiers":["CVE-2026-98520"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-10-26T01:39:40.4466127+00:00","complete":true,"records":1756,"lastAttemptAt":"2026-10-26T01:39:40.4466127+00:00","lastSuccessAt":"2026-10-26T01:39:40.5904839+00:00","error":null,"lastVerifiedAt":"2026-10-26T01:39:40.5904859+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-1a687ad2a0b90150aa7d97c9f39e63de695ae2db23e31ebc28df1492c461b23c-8739c76e681f900923b900c9df0ef75cf421d39cabb54650c4b9ad19b6a76d85","complete":true,"records":414048,"lastAttemptAt":"2026-10-26T01:37:59.9284441+00:00","lastSuccessAt":"2026-10-26T00:46:56.7731374+00:00","error":null,"lastVerifiedAt":"2026-10-26T01:37:59.9284441+00:00","snapshotPublishedAt":"2026-10-26T00:42:27+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-43321610382942b8ad8c85917eab1546","complete":false,"records":4735,"lastAttemptAt":"2026-10-26T01:39:43.2271706+00:00","lastSuccessAt":"2026-10-24T23:18:49.862+00:00","error":"InvalidDataException","lastVerifiedAt":"2026-10-24T23:18:49.862+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":4764,"expectedIdentifiers":13474},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-10-26T01:39:40.4466127+00:00","complete":true,"records":1093,"lastAttemptAt":"2026-10-26T01:39:40.4466127+00:00","lastSuccessAt":"2026-10-26T01:39:40.7020356+00:00","error":null,"lastVerifiedAt":"2026-10-26T01:39:40.702037+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-204a3fb93a00487e8f7f36db01dc851d","complete":true,"records":13413,"lastAttemptAt":"2026-10-26T01:39:41.1738985+00:00","lastSuccessAt":"2026-10-25T16:19:28.681+00:00","error":null,"lastVerifiedAt":"2026-10-25T16:19:28.681+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13474,"expectedIdentifiers":13474},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-2375a4e597279abf92e8747e140fe8da9d421877cd49cae3ac69a2cb78469b2c","complete":true,"records":9779,"lastAttemptAt":"2026-10-26T01:39:40.0161298+00:00","lastSuccessAt":"2026-10-24T13:19:53.1346702+00:00","error":null,"lastVerifiedAt":"2026-10-26T01:39:40.0161298+00:00","snapshotPublishedAt":"2026-10-24T03:03:12+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-16ad89dfea13ab9e9b0108e63a759d63bd4559cc68b58491107d62ee35bbbaf2","complete":true,"records":1965,"lastAttemptAt":"2026-10-26T01:38:00.2986867+00:00","lastSuccessAt":"2026-10-23T16:01:26.4487605+00:00","error":null,"lastVerifiedAt":"2026-10-26T01:38:00.2986867+00:00","snapshotPublishedAt":"2026-10-21T12:18:07+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-7da67a15aa6e56a0e3081a7646dc74d537e6ef974afc593c2b1794ed01970648","complete":true,"records":2969,"lastAttemptAt":"2026-10-26T01:39:40.3984093+00:00","lastSuccessAt":"2026-10-24T13:19:59.1145547+00:00","error":null,"lastVerifiedAt":"2026-10-26T01:39:40.3984093+00:00","snapshotPublishedAt":"2026-10-24T08:47:51+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-e467025c473777f37ebf674fb135c1da680991784fbaabf4bddec7123f3aa848","complete":true,"records":230789,"lastAttemptAt":"2026-10-26T01:39:39.8952597+00:00","lastSuccessAt":"2026-10-26T01:39:38.7072227+00:00","error":null,"lastVerifiedAt":"2026-10-26T01:39:39.8952597+00:00","snapshotPublishedAt":"2026-10-26T01:18:10+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null}]}