{"id":"CVE-2026-93238","state":"PUBLISHED","title":"s390/vfio-ap: fix potential use of uninitialized apm_filtered bitmap","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/vfio-ap: fix potential use of uninitialized apm_filtered bitmap\n\nThe DECLARE_BITMAP(apm_filtered, AP_DEVICES) macro allocates the bitmap\non the stack without zero-initializing it.\n\nIn vfio_ap_mdev_hot_plug_cfg(), the vfio_ap_mdev_filter_matrix() function\nis only called to initialize and populate apm_filtered if either\nfilter_adapters or filter_domains is true. If the hot plug configuration\nchange only adds control domains (meaning filter_cdoms is true, but\nfilter_adapters and filter_domains are both false),\nvfio_ap_mdev_filter_matrix() is bypassed.\n\nConsequently, apm_filtered is passed to reset_queues_for_apids() with\nuninitialized stack garbage. This can cause reset_queues_for_apids() to\ninterpret arbitrary stack garbage bits as valid APIDs to reset, potentially\nperforming unintended guest hardware queue resets.\n\nFix this by zero-initializing the apm_filtered bitmap at the beginning of\nvfio_ap_mdev_hot_plug_cfg() using bitmap_zero().","publishedAt":"2026-09-24T15:34:11.543Z","updatedAt":"2026-10-19T09:07:49.811Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"eeb386aeb5b7c8d2dae6a3ba49255d8a97803182","status":"affected","lessThan":"4ba8a08f5f26ed59f356a6318bca3aa7cc0af3e2","versionType":"git"},{"version":"eeb386aeb5b7c8d2dae6a3ba49255d8a97803182","status":"affected","lessThan":"f73db632524320d2b93bc8534be8ea875053502d","versionType":"git"},{"version":"eeb386aeb5b7c8d2dae6a3ba49255d8a97803182","status":"affected","lessThan":"6d554f2571e6b4db242593ba561efd6a6d1f99a9","versionType":"git"},{"version":"eeb386aeb5b7c8d2dae6a3ba49255d8a97803182","status":"affected","lessThan":"09548edc6114f1eb1035b30795e893204ef45b85","versionType":"git"},{"version":"eeb386aeb5b7c8d2dae6a3ba49255d8a97803182","status":"affected","lessThan":"bf09b9d7cd7890bc3a3b7eb63d5ece15f88bfde7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/s390/crypto/vfio_ap_ops.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.0","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","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":["drivers/s390/crypto/vfio_ap_ops.c"]}],"references":["https://git.kernel.org/stable/c/4ba8a08f5f26ed59f356a6318bca3aa7cc0af3e2","https://git.kernel.org/stable/c/f73db632524320d2b93bc8534be8ea875053502d","https://git.kernel.org/stable/c/6d554f2571e6b4db242593ba561efd6a6d1f99a9","https://git.kernel.org/stable/c/09548edc6114f1eb1035b30795e893204ef45b85","https://git.kernel.org/stable/c/bf09b9d7cd7890bc3a3b7eb63d5ece15f88bfde7"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:34.582Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/93xxx/CVE-2026-93238.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-93238","state":"PUBLISHED","datePublished":"2026-09-24T15:34:11.543Z","dateUpdated":"2026-10-19T09:07:49.811Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-17T16:02:15.095Z"},"containers":{"cna":{"title":"s390/vfio-ap: fix potential use of uninitialized apm_filtered bitmap","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/vfio-ap: fix potential use of uninitialized apm_filtered bitmap\n\nThe DECLARE_BITMAP(apm_filtered, AP_DEVICES) macro allocates the bitmap\non the stack without zero-initializing it.\n\nIn vfio_ap_mdev_hot_plug_cfg(), the vfio_ap_mdev_filter_matrix() function\nis only called to initialize and populate apm_filtered if either\nfilter_adapters or filter_domains is true. If the hot plug configuration\nchange only adds control domains (meaning filter_cdoms is true, but\nfilter_adapters and filter_domains are both false),\nvfio_ap_mdev_filter_matrix() is bypassed.\n\nConsequently, apm_filtered is passed to reset_queues_for_apids() with\nuninitialized stack garbage. This can cause reset_queues_for_apids() to\ninterpret arbitrary stack garbage bits as valid APIDs to reset, potentially\nperforming unintended guest hardware queue resets.\n\nFix this by zero-initializing the apm_filtered bitmap at the beginning of\nvfio_ap_mdev_hot_plug_cfg() using bitmap_zero()."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"eeb386aeb5b7c8d2dae6a3ba49255d8a97803182","status":"affected","lessThan":"4ba8a08f5f26ed59f356a6318bca3aa7cc0af3e2","versionType":"git"},{"version":"eeb386aeb5b7c8d2dae6a3ba49255d8a97803182","status":"affected","lessThan":"f73db632524320d2b93bc8534be8ea875053502d","versionType":"git"},{"version":"eeb386aeb5b7c8d2dae6a3ba49255d8a97803182","status":"affected","lessThan":"6d554f2571e6b4db242593ba561efd6a6d1f99a9","versionType":"git"},{"version":"eeb386aeb5b7c8d2dae6a3ba49255d8a97803182","status":"affected","lessThan":"09548edc6114f1eb1035b30795e893204ef45b85","versionType":"git"},{"version":"eeb386aeb5b7c8d2dae6a3ba49255d8a97803182","status":"affected","lessThan":"bf09b9d7cd7890bc3a3b7eb63d5ece15f88bfde7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/s390/crypto/vfio_ap_ops.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.0","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","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":["drivers/s390/crypto/vfio_ap_ops.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/4ba8a08f5f26ed59f356a6318bca3aa7cc0af3e2"},{"url":"https://git.kernel.org/stable/c/f73db632524320d2b93bc8534be8ea875053502d"},{"url":"https://git.kernel.org/stable/c/6d554f2571e6b4db242593ba561efd6a6d1f99a9"},{"url":"https://git.kernel.org/stable/c/09548edc6114f1eb1035b30795e893204ef45b85"},{"url":"https://git.kernel.org/stable/c/bf09b9d7cd7890bc3a3b7eb63d5ece15f88bfde7"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:07:49.811Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.18.51"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"7.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}