{"id":"CVE-2021-47225","state":"PUBLISHED","title":"mac80211: fix deadlock in AP/VLAN handling","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmac80211: fix deadlock in AP/VLAN handling\n\nSyzbot reports that when you have AP_VLAN interfaces that are up\nand close the AP interface they belong to, we get a deadlock. No\nsurprise - since we dev_close() them with the wiphy mutex held,\nwhich goes back into the netdev notifier in cfg80211 and tries to\nacquire the wiphy mutex there.\n\nTo fix this, we need to do two things:\n 1) prevent changing iftype while AP_VLANs are up, we can't\n    easily fix this case since cfg80211 already calls us with\n    the wiphy mutex held, but change_interface() is relatively\n    rare in drivers anyway, so changing iftype isn't used much\n    (and userspace has to fall back to down/change/up anyway)\n 2) pull the dev_close() loop over VLANs out of the wiphy mutex\n    section in the normal stop case","publishedAt":"2024-05-21T14:19:30.212Z","updatedAt":"2026-05-11T13:50:22.960Z","severity":{"score":5.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"a05829a7222e9d10c416dd2dbbf3929fe6646b89","status":"affected","lessThan":"8043903fcb72f545c52e3ec74d6fd82ef79ce7c5","versionType":"git"},{"version":"a05829a7222e9d10c416dd2dbbf3929fe6646b89","status":"affected","lessThan":"d5befb224edbe53056c2c18999d630dafb4a08b9","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/iface.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.12","versionType":"semver"},{"version":"5.12.13","status":"unaffected","lessThanOrEqual":"5.12.*","versionType":"semver"},{"version":"5.13","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/iface.c"]}],"references":["https://git.kernel.org/stable/c/8043903fcb72f545c52e3ec74d6fd82ef79ce7c5","https://git.kernel.org/stable/c/d5befb224edbe53056c2c18999d630dafb4a08b9"],"weaknesses":[],"ingestedAt":"2026-10-29T19:49:19.404Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2021/47xxx/CVE-2021-47225.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2021-47225","state":"PUBLISHED","datePublished":"2024-05-21T14:19:30.212Z","dateUpdated":"2026-05-11T13:50:22.960Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-04-10T18:59:19.529Z"},"containers":{"cna":{"title":"mac80211: fix deadlock in AP/VLAN handling","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmac80211: fix deadlock in AP/VLAN handling\n\nSyzbot reports that when you have AP_VLAN interfaces that are up\nand close the AP interface they belong to, we get a deadlock. No\nsurprise - since we dev_close() them with the wiphy mutex held,\nwhich goes back into the netdev notifier in cfg80211 and tries to\nacquire the wiphy mutex there.\n\nTo fix this, we need to do two things:\n 1) prevent changing iftype while AP_VLANs are up, we can't\n    easily fix this case since cfg80211 already calls us with\n    the wiphy mutex held, but change_interface() is relatively\n    rare in drivers anyway, so changing iftype isn't used much\n    (and userspace has to fall back to down/change/up anyway)\n 2) pull the dev_close() loop over VLANs out of the wiphy mutex\n    section in the normal stop case"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"a05829a7222e9d10c416dd2dbbf3929fe6646b89","status":"affected","lessThan":"8043903fcb72f545c52e3ec74d6fd82ef79ce7c5","versionType":"git"},{"version":"a05829a7222e9d10c416dd2dbbf3929fe6646b89","status":"affected","lessThan":"d5befb224edbe53056c2c18999d630dafb4a08b9","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/iface.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.12","versionType":"semver"},{"version":"5.12.13","status":"unaffected","lessThanOrEqual":"5.12.*","versionType":"semver"},{"version":"5.13","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/iface.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/8043903fcb72f545c52e3ec74d6fd82ef79ce7c5"},{"url":"https://git.kernel.org/stable/c/d5befb224edbe53056c2c18999d630dafb4a08b9"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T13:50:22.960Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"5.12.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"5.13"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":5.5,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"timestamp":"2024-05-31T18:48:57.781631Z","id":"CVE-2021-47225","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"problemTypes":[{"descriptions":[{"type":"CWE","lang":"en","description":"CWE-noinfo Not enough information"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2024-11-07T15:04:13.223Z"}},{"title":"CVE Program Container","references":[{"url":"https://git.kernel.org/stable/c/8043903fcb72f545c52e3ec74d6fd82ef79ce7c5","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/d5befb224edbe53056c2c18999d630dafb4a08b9","tags":["x_transferred"]}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2024-08-04T05:32:07.429Z"}}]}}}