{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98515", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.354Z", "datePublished": "2026-10-18T15:17:31.953Z", "dateUpdated": "2026-10-24T14:09:13.699Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-24T14:09:13.699Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/nouveau: fix double-free in nvif_vmm_dtor\n\nOn failure, nouveau_cli_init() calls nouveau_cli_fini() to tear\nthe client down. Then, nouveau_drm_open() also enters into its\ncleanup path and calls nouveau_cli_fini() AGAIN. nouveau_cli_fini()\ncalls nouveau_vmm_fini():\n\n\tvoid\n\tnouveau_vmm_fini(struct nouveau_vmm *vmm)\n\t{\n\t\tnouveau_svmm_fini(&vmm->svmm);\n\t\tnvif_vmm_dtor(&vmm->vmm);\n\t\tvmm->cli = NULL;\n\t}\n\nInside nvif_vmm_dtor(), vmm->page is freed unconditionally:\n\n\tvoid\n\tnvif_vmm_dtor(struct nvif_vmm *vmm)\n\t{\n\t\tkfree(vmm->page);\n\t\tnvif_object_dtor(&vmm->object);\n\t}\n\nvmm->page is never cleared after being freed, so the second call of\nnvif_vmm_dtor() will cause a double-free.\n\nFound by fuzzing the nouveau driver with a modified Syzkaller:\n\n\tBUG: KASAN: double-free in nvif_vmm_dtor+0x31/0x50 drivers/gpu/drm/nouveau/nvif/vmm.c:194\n\tFree of addr ffff888010fcdc30 by task syz.0.173/2567\n\n\tCPU: 1 UID: 0 PID: 2567 Comm: syz.0.173 Not tainted 7.2.0 #24 PREEMPT(lazy)\n\tHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n\tCall Trace:\n\t\n\t__dump_stack lib/dump_stack.c:94 [inline]\n\tdump_stack_lvl+0x95/0xe0 lib/dump_stack.c:120\n\tprint_address_description mm/kasan/report.c:378 [inline]\n\tprint_report+0xcb/0x5a0 mm/kasan/report.c:482\n\tkasan_report_invalid_free+0xaa/0xd0 mm/kasan/report.c:557\n\tcheck_slab_allocation+0xe4/0x110 mm/kasan/common.c:235\n\tkasan_slab_pre_free include/linux/kasan.h:199 [inline]\n\tslab_free_hook mm/slub.c:2622 [inline]\n\tslab_free mm/slub.c:6377 [inline]\n\tkfree+0x192/0x590 mm/slub.c:6692\n\tnvif_vmm_dtor+0x31/0x50 drivers/gpu/drm/nouveau/nvif/vmm.c:194\n\tnouveau_vmm_fini+0x16/0x50 drivers/gpu/drm/nouveau/nouveau_vmm.c:127\n\tnouveau_cli_fini+0x10e/0x210 drivers/gpu/drm/nouveau/nouveau_drm.c:225\n\tnouveau_drm_open+0x24e/0x740 drivers/gpu/drm/nouveau/nouveau_drm.c:1255\n\tdrm_file_alloc+0x5f2/0xad0 drivers/gpu/drm/drm_file.c:176\n\tdrm_open_helper+0x1d7/0x4a0 drivers/gpu/drm/drm_file.c:335\n\tdrm_open+0x190/0x3d0 drivers/gpu/drm/drm_file.c:388\n\tdrm_stub_open+0x1f2/0x460 drivers/gpu/drm/drm_drv.c:1211\n\tchrdev_open+0x21c/0x660 fs/char_dev.c:411\n\tdo_dentry_open+0x59d/0x12b0 fs/open.c:947\n\tvfs_open+0x82/0x390 fs/open.c:1052\n\tdo_open fs/namei.c:4700 [inline]\n\tpath_openat+0x2345/0x3420 fs/namei.c:4863\n\tdo_file_open+0x207/0x460 fs/namei.c:4892\n\tdo_sys_openat2+0xd1/0x1d0 fs/open.c:1368\n\tdo_sys_open fs/open.c:1374 [inline]\n\t__do_sys_openat fs/open.c:1390 [inline]\n\t__se_sys_openat fs/open.c:1385 [inline]\n\t__x64_sys_openat+0x144/0x200 fs/open.c:1385\n\tdo_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n\tdo_syscall_64+0x115/0x690 arch/x86/entry/syscall_64.c:94\n\tentry_SYSCALL_64_after_hwframe+0x77/0x7f\n\tRIP: 0033:0x7fc6d687594d\n\tCode: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48\n\tRSP: 002b:00007fc6d5295008 EFLAGS: 00000246 ORIG_RAX: 0000000000000101\n\tRAX: ffffffffffffffda RBX: 00007fc6d6b06180 RCX: 00007fc6d687594d\n\tRDX: 0000000000022501 RSI: 0000200000000000 RDI: ffffffffffffff9c\n\tRBP: 00007fc6d691c303 R08: 0000000000000000 R09: 0000000000000000\n\tR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\n\tR13: 00007fc6d6b06218 R14: 00007fc6d6b06180 R15: 00007ffd9451d760\n\t\n\n\tAllocated by task 2567 on cpu 1 at 163.593900s:\n\tkasan_save_stack+0x24/0x50 mm/kasan/common.c:57\n\tkasan_save_track+0x17/0x60 mm/kasan/common.c:78\n\tpoison_kmalloc_redzone mm/kasan/common.c:398 [inline]\n\t__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415\n\tkasan_kmalloc include/linux/kasan.h:263 [inline]\n\t__do_kmalloc_node mm/slub.c:5334 [inline]\n\t__kmalloc_noprof+0x304/0x7c0 mm/slub.c:5359\n\t_kmalloc_noprof include/linux/slab.h:992 [inline]\n\tnvif_vmm_ctor+0x3c0/0x7e0 drivers/gpu/drm/nouveau/nvif/vmm.c:237\n\tnouveau_vmm_init+0x40/0x90 drivers/gpu/drm/nouveau/nouveau_vmm.c:134\n\tnouveau_cli_init+0x7b9/0\n---truncated---" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - An attacker reaches patched nvif_vmm_dtor() by locally opening a Nouveau DRM node: openat() → drm_open() → drm_file_alloc() → nouveau_drm_open() → nouveau_cli_init()/nouveau_cli_fini() → nouveau_vmm_fini(). No network or radio data enters this path.\nAC:L - Each successful open creates per-client VMM state and a dedicated scheduler workqueue; repeated opens and memory pressure can make the later nvif_mclass() or nouveau_sched_create() allocation fail after vmm->page exists. The two unwinders then deterministically call nvif_vmm_dtor() twice, with no race.\nPR:L - Nouveau advertises DRIVER_RENDER, and drm_file_alloc() invokes nouveau_drm_open() for /dev/dri/renderD* without a capable(), DRM-master, or authentication check. A local unprivileged user with ordinary render-node access suffices.\nUI:N - The attacker performs the render-node opens and resource-pressure sequence themselves; no other user must mount media, open a file, or take any action.\nS:U - The duplicate free corrupts the host kernel's own slab allocator and may yield local kernel privilege escalation, but it does not cross a VM, IOMMU, or other distinct security authority.\nC:H - nvif_vmm_dtor() frees the same kmalloc-backed vmm->page object twice, allowing its slab slot to be returned twice and reclaimed as overlapping allocations. Heap grooming can expose contents written through the aliased kernel object, enabling kernel-memory disclosure.\nI:H - The duplicate kfree(vmm->page) corrupts the SLUB freelist; later allocations can alias the same slot, so writes through one allocation corrupt the other and can be developed into arbitrary-write or control-flow-hijack primitives.\nA:H - The reported path produces an immediate KASAN double-free in nvif_vmm_dtor(); without KASAN it can trigger SLUB's hardened double-free BUG or corrupt the freelist and cause a subsequent kernel oops or panic." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/gpu/drm/nouveau/nouveau_drm.c", "drivers/gpu/drm/nouveau/nvif/vmm.c" ], "versions": [ { "version": "20d8a88e557aae5264e793f4626c45cd644c7144", "lessThan": "023e7a01f8fb27799f0987b5bcda325d73a2904c", "status": "affected", "versionType": "git" }, { "version": "20d8a88e557aae5264e793f4626c45cd644c7144", "lessThan": "375901ac0f286e81be00a4126e57d488cb401884", "status": "affected", "versionType": "git" }, { "version": "20d8a88e557aae5264e793f4626c45cd644c7144", "lessThan": "bf542ecd4f60d4689818d194e7ca74772fe0f8b5", "status": "affected", "versionType": "git" }, { "version": "20d8a88e557aae5264e793f4626c45cd644c7144", "lessThan": "f09f4a536935b15539f2de9fe775a2641202be90", "status": "affected", "versionType": "git" }, { "version": "20d8a88e557aae5264e793f4626c45cd644c7144", "lessThan": "279e5ac137370e274a09dd552547ae6bddd0d4d5", "status": "affected", "versionType": "git" }, { "version": "20d8a88e557aae5264e793f4626c45cd644c7144", "lessThan": "109a8d2d5b7d2719ebe09df3f9241023900b3846", "status": "affected", "versionType": "git" }, { "version": "20d8a88e557aae5264e793f4626c45cd644c7144", "lessThan": "872a5473c02a26c955be44d52b7ab2f8ea70a2cf", "status": "affected", "versionType": "git" }, { "version": "20d8a88e557aae5264e793f4626c45cd644c7144", "lessThan": "97077ac87afe9e91ec074ef0be64454e7ccbf344", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/gpu/drm/nouveau/nouveau_drm.c", "drivers/gpu/drm/nouveau/nvif/vmm.c" ], "versions": [ { "version": "4.11", "status": "affected" }, { "version": "0", "lessThan": "4.11", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.271", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.222", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.189", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.158", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.112", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.55", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.9", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.10.271" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.15.222" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.1.189" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.6.158" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.12.112" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.18.55" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "7.2.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/023e7a01f8fb27799f0987b5bcda325d73a2904c" }, { "url": "https://git.kernel.org/stable/c/375901ac0f286e81be00a4126e57d488cb401884" }, { "url": "https://git.kernel.org/stable/c/bf542ecd4f60d4689818d194e7ca74772fe0f8b5" }, { "url": "https://git.kernel.org/stable/c/f09f4a536935b15539f2de9fe775a2641202be90" }, { "url": "https://git.kernel.org/stable/c/279e5ac137370e274a09dd552547ae6bddd0d4d5" }, { "url": "https://git.kernel.org/stable/c/109a8d2d5b7d2719ebe09df3f9241023900b3846" }, { "url": "https://git.kernel.org/stable/c/872a5473c02a26c955be44d52b7ab2f8ea70a2cf" }, { "url": "https://git.kernel.org/stable/c/97077ac87afe9e91ec074ef0be64454e7ccbf344" } ], "title": "drm/nouveau: fix double-free in nvif_vmm_dtor", "x_generator": { "engine": "bippy-1.2.0" } } } }