{"id":"CVE-2022-50675","summary":"arm64: mte: Avoid setting PG_mte_tagged if no tags cleared or restored","details":"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-\u003eflags) 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-\u003eflags\").\nWhen this commit was reverted (20794545c146), KASAN started reporting\naccess faults because the overriding tags in a page did not match the\noriginal page-\u003eflags (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()).","modified":"2026-03-20T11:47:34.757071Z","published":"2025-12-09T01:29:27.926Z","related":["SUSE-SU-2026:0263-1","SUSE-SU-2026:0317-1","SUSE-SU-2026:0411-1","SUSE-SU-2026:0617-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50675.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/749e9fc18b1e1a3f93a9512e91bd7f93002d2821"},{"type":"WEB","url":"https://git.kernel.org/stable/c/918002bdbe4328c8c0164a22e8ebf2384b80dc23"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a8e5e5146ad08d794c58252bab00b261045ef16d"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50675.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2022-50675"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"69e3b846d8a753f9f279f29531ca56b0f7563ad0"},{"fixed":"918002bdbe4328c8c0164a22e8ebf2384b80dc23"},{"fixed":"749e9fc18b1e1a3f93a9512e91bd7f93002d2821"},{"fixed":"a8e5e5146ad08d794c58252bab00b261045ef16d"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2022-50675.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.14.0"},{"fixed":"5.15.82"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.0.3"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2022-50675.json"}}],"schema_version":"1.7.5"}