{"id":"CVE-2026-98650","state":"PUBLISHED","title":"KVM: s390: Fix potential races in dat skey functions","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: s390: Fix potential races in dat skey functions\n\nWhen dat_cond_set_storage_key() finds a large page, it will\nconditionally set the storage key in absolute memory using\nlarge_crste_to_phys() to get the absolute address.\n\nThere is a race window between dat_entry_walk() and\nlarge_crste_to_phys(): the large page could have been split\nconcurrently, and large_crste_to_phys() might be called with a crste\nthat does not designate a large page, leading to crashes.\n\nSimilar issues were also present in dat_set_storage_key().\n\ndat_get_storage_key() and dat_reset_reference_bit() did instead check\nfor a potential concurrent splitting of the large page, but then\nhandled it incorrectly.\n\nFix by performing a READ_ONCE on the crste pointer, checking and using\nthe result, instead of dereferencing the pointer again. In case a race\nis detacted, try dat_entry_walk() again.","publishedAt":"2026-10-18T15:20:22.173Z","updatedAt":"2026-10-19T09:23:19.769Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"8e03e8316eb242af307d1c789d09f1a1457cf9a3","status":"affected","lessThan":"c958f0498891203fddf2764b28f8b102c6bfd719","versionType":"git"},{"version":"8e03e8316eb242af307d1c789d09f1a1457cf9a3","status":"affected","lessThan":"27554b9505ddfc0aeab466aeb60929dfa17284c7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/s390/kvm/gmap/dat.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"7.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"7.0","versionType":"semver"},{"version":"7.2.9","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/s390/kvm/gmap/dat.c"]}],"references":["https://git.kernel.org/stable/c/c958f0498891203fddf2764b28f8b102c6bfd719","https://git.kernel.org/stable/c/27554b9505ddfc0aeab466aeb60929dfa17284c7"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/98xxx/CVE-2026-98650.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98650","state":"PUBLISHED","datePublished":"2026-10-18T15:20:22.173Z","dateUpdated":"2026-10-19T09:23:19.769Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.362Z"},"containers":{"cna":{"title":"KVM: s390: Fix potential races in dat skey functions","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: s390: Fix potential races in dat skey functions\n\nWhen dat_cond_set_storage_key() finds a large page, it will\nconditionally set the storage key in absolute memory using\nlarge_crste_to_phys() to get the absolute address.\n\nThere is a race window between dat_entry_walk() and\nlarge_crste_to_phys(): the large page could have been split\nconcurrently, and large_crste_to_phys() might be called with a crste\nthat does not designate a large page, leading to crashes.\n\nSimilar issues were also present in dat_set_storage_key().\n\ndat_get_storage_key() and dat_reset_reference_bit() did instead check\nfor a potential concurrent splitting of the large page, but then\nhandled it incorrectly.\n\nFix by performing a READ_ONCE on the crste pointer, checking and using\nthe result, instead of dereferencing the pointer again. In case a race\nis detacted, try dat_entry_walk() again."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"8e03e8316eb242af307d1c789d09f1a1457cf9a3","status":"affected","lessThan":"c958f0498891203fddf2764b28f8b102c6bfd719","versionType":"git"},{"version":"8e03e8316eb242af307d1c789d09f1a1457cf9a3","status":"affected","lessThan":"27554b9505ddfc0aeab466aeb60929dfa17284c7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/s390/kvm/gmap/dat.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"7.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"7.0","versionType":"semver"},{"version":"7.2.9","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/s390/kvm/gmap/dat.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/c958f0498891203fddf2764b28f8b102c6bfd719"},{"url":"https://git.kernel.org/stable/c/27554b9505ddfc0aeab466aeb60929dfa17284c7"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:23:19.769Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.0","versionEndExcluding":"7.2.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.0","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}