{"cve":"CVE-2022-50675","nvd":{"published":"2025-12-09T16:17:19.730","modified":"2026-06-17T05:23:58.663","status":"Deferred","description":"In the Linux kernel, the following vulnerability has been resolved:\n\narm64: mte: Avoid setting PG_mte_tagged if no tags cleared or restored\n\nPrior to commit 69e3b846d8a7 (\"arm64: mte: Sync tags for pages where PTE\nis untagged\"), mte_sync_tags() was only called for pte_tagged() entries\n(those mapped with PROT_MTE). Therefore mte_sync_tags() could safely use\ntest_and_set_bit(PG_mte_tagged, &page->flags) without inadvertently\nsetting PG_mte_tagged on an untagged page.\n\nThe above commit was required as guests may enable MTE without any\ncontrol at the stage 2 mapping, nor a PROT_MTE mapping in the VMM.\nHowever, the side-effect was that any page with a PTE that looked like\nswap (or migration) was getting PG_mte_tagged set automatically. A\nsubsequent page copy (e.g. migration) copied the tags to the destination\npage even if the tags were owned by KASAN.\n\nThis issue was masked by the page_kasan_tag_reset() call introduced in\ncommit e5b8d9218951 (\"arm64: mte: reset the page tag in page->flags\").\nWhen this commit was reverted (20794545c146), KASAN started reporting\naccess faults because the overriding tags in a page did not match the\noriginal page->flags (with CONFIG_KASAN_HW_TAGS=y):\n\n  BUG: KASAN: invalid-access in copy_page+0x10/0xd0 arch/arm64/lib/copy_page.S:26\n  Read at addr f5ff000017f2e000 by task syz-executor.1/2218\n  Pointer tag: [f5], memory tag: [f2]\n\nMove the PG_mte_tagged bit setting from mte_sync_tags() to the actual\nplace where tags are cleared (mte_sync_page_tags()) or restored\n(mte_restore_tags()).","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/749e9fc18b1e1a3f93a9512e91bd7f93002d2821","https://git.kernel.org/stable/c/918002bdbe4328c8c0164a22e8ebf2384b80dc23","https://git.kernel.org/stable/c/a8e5e5146ad08d794c58252bab00b261045ef16d"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:16:40.427100871+00:00"},"epss":{"cve":"CVE-2022-50675","score":0.00242,"percentile":0.15363,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}