{"id":"CVE-2026-68239","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-68239","generatedAt":"2026-10-28T05:58:31.901Z","title":"In the Linux kernel, the following vulnerability has been resolved: drm/ttm: Account for NULL and handle pages in ttm_pool_backup Pages in ttm_pool_backup can be NULL or backup handles (ttm_backup_page_ptr_is_handle()), neither of which can be passed to…","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/ttm: Account for NULL and handle pages in ttm_pool_backup\n\nPages in ttm_pool_backup can be NULL or backup handles\n(ttm_backup_page_ptr_is_handle()), neither of which can be passed to\nset_pages_array_wb() or freed. Add a dedicated WB pass before the\ndma/purge loop that walks allocations using the same i += num_pages\nstride, skipping NULL and handle entries, and calls set_pages_array_wb()\nonce per contiguous run of real pages. Apply the same NULL/handle guard\nto the dma/purge loop.\n\nFixes the following oops:\n\nOops: general protection fault, kernel NULL pointer dereference 0x0: 0000 [#1] SMP NOPTI\nRIP: 0010:__cpa_process_fault+0xf8/0x770\nRSP: 0018:ffffc90000a87718 EFLAGS: 00010287\nRAX: 0000000000000000 RBX: ffffc90000a87868 RCX: 0000000000000000\nRDX: 0000000000001000 RSI: 0005088000000000 RDI: ffffffff827c5f34\nRBP: 0005088000000000 R08: ffffc90000a877cb R09: ffffc90000a877d0\nR10: 0000000000000000 R11: 000000000000001b R12: 000ffffffffff000\nR13: ffffc90000a87868 R14: ffffc90000a87868 R15: ffff88815b882ae0\nFS:  0000000000000000(0000) GS:ffff8884ec840000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00007f930b844000 CR3: 000000000262e003 CR4: 0000000008f70ef0\nPKRU: 55555554\nCall Trace:\n <TASK>\n __change_page_attr_set_clr+0x989/0xe90\n ? __purge_vmap_area_lazy+0x6c/0x3a0\n ? _vm_unmap_aliases+0x250/0x2a0\n set_pages_array_wb+0x7f/0x120\n ttm_pool_backup+0x4c9/0x5b0 [ttm]\n ? dma_resv_wait_timeout+0x3b/0xf0\n ttm_tt_backup+0x32/0x60 [ttm]\n ttm_bo_shrink+0x66/0x110 [ttm]\n xe_bo_shrink_purge+0x12b/0x1b0 [xe]\n xe_bo_shrink+0xbb/0x270 [xe]\n __xe_shrinker_walk+0xf7/0x160 [xe]\n xe_shrinker_walk+0x9d/0xc0 [xe]\n xe_shrinker_scan+0x11f/0x210 [xe]\n do_shrink_slab+0x13b/0x270\n shrink_slab+0xf1/0x400\n shrink_node+0x352/0x8a0\n balance_pgdat+0x32c/0x700\n kswapd+0x205/0x2f0\n ? __pfx_autoremove_wake_function+0x10/0x10\n ? __pfx_kswapd+0x10/0x10\n kthread+0xd1/0x110\n ? __pfx_kthread+0x10/0x10\n ret_from_fork+0x1b1/0x200\n ? __pfx_kthread+0x10/0x10\n ret_from_fork_asm+0x1a/0x30\n </TASK>","published":"2026-08-10T13:20:12.000Z","lastModified":"2026-08-17T05:18:26.000Z","status":"Received","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":null,"cwe":[],"affected":[],"epss":{"score":0.00166,"percentile":0.05792,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"unknown","text":"Not yet scored. NVD analysis is pending; check back once CVSS and EPSS values are published."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/22aa7fb4e7d0b3ab41d1240ed743167980912970","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5b7b3b6595ee77d01c7463757baed114786094dd","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9ddaabf38f7a45b329e34358b98d2968d8649d21","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-68239","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}