{"api_version":"1","generated_at":"2026-08-04T23:14:02+00:00","cve":"CVE-2025-38248","urls":{"html":"https://cve.report/CVE-2025-38248","api":"https://cve.report/api/cve/CVE-2025-38248.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2025-38248","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-38248"},"summary":{"title":"bridge: mcast: Fix use-after-free during router port configuration","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbridge: mcast: Fix use-after-free during router port configuration\n\nThe bridge maintains a global list of ports behind which a multicast\nrouter resides. The list is consulted during forwarding to ensure\nmulticast packets are forwarded to these ports even if the ports are not\nmember in the matching MDB entry.\n\nWhen per-VLAN multicast snooping is enabled, the per-port multicast\ncontext is disabled on each port and the port is removed from the global\nrouter port list:\n\n # ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1\n # ip link add name dummy1 up master br1 type dummy\n # ip link set dev dummy1 type bridge_slave mcast_router 2\n $ bridge -d mdb show | grep router\n router ports on br1: dummy1\n # ip link set dev br1 type bridge mcast_vlan_snooping 1\n $ bridge -d mdb show | grep router\n\nHowever, the port can be re-added to the global list even when per-VLAN\nmulticast snooping is enabled:\n\n # ip link set dev dummy1 type bridge_slave mcast_router 0\n # ip link set dev dummy1 type bridge_slave mcast_router 2\n $ bridge -d mdb show | grep router\n router ports on br1: dummy1\n\nSince commit 4b30ae9adb04 (\"net: bridge: mcast: re-implement\nbr_multicast_{enable, disable}_port functions\"), when per-VLAN multicast\nsnooping is enabled, multicast disablement on a port will disable the\nper-{port, VLAN} multicast contexts and not the per-port one. As a\nresult, a port will remain in the global router port list even after it\nis deleted. This will lead to a use-after-free [1] when the list is\ntraversed (when adding a new port to the list, for example):\n\n # ip link del dev dummy1\n # ip link add name dummy2 up master br1 type dummy\n # ip link set dev dummy2 type bridge_slave mcast_router 2\n\nSimilarly, stale entries can also be found in the per-VLAN router port\nlist. When per-VLAN multicast snooping is disabled, the per-{port, VLAN}\ncontexts are disabled on each port and the port is removed from the\nper-VLAN router port list:\n\n # ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1 mcast_vlan_snooping 1\n # ip link add name dummy1 up master br1 type dummy\n # bridge vlan add vid 2 dev dummy1\n # bridge vlan global set vid 2 dev br1 mcast_snooping 1\n # bridge vlan set vid 2 dev dummy1 mcast_router 2\n $ bridge vlan global show dev br1 vid 2 | grep router\n       router ports: dummy1\n # ip link set dev br1 type bridge mcast_vlan_snooping 0\n $ bridge vlan global show dev br1 vid 2 | grep router\n\nHowever, the port can be re-added to the per-VLAN list even when\nper-VLAN multicast snooping is disabled:\n\n # bridge vlan set vid 2 dev dummy1 mcast_router 0\n # bridge vlan set vid 2 dev dummy1 mcast_router 2\n $ bridge vlan global show dev br1 vid 2 | grep router\n       router ports: dummy1\n\nWhen the VLAN is deleted from the port, the per-{port, VLAN} multicast\ncontext will not be disabled since multicast snooping is not enabled\non the VLAN. As a result, the port will remain in the per-VLAN router\nport list even after it is no longer member in the VLAN. This will lead\nto a use-after-free [2] when the list is traversed (when adding a new\nport to the list, for example):\n\n # ip link add name dummy2 up master br1 type dummy\n # bridge vlan add vid 2 dev dummy2\n # bridge vlan del vid 2 dev dummy1\n # bridge vlan set vid 2 dev dummy2 mcast_router 2\n\nFix these issues by removing the port from the relevant (global or\nper-VLAN) router port list in br_multicast_port_ctx_deinit(). The\nfunction is invoked during port deletion with the per-port multicast\ncontext and during VLAN deletion with the per-{port, VLAN} multicast\ncontext.\n\nNote that deleting the multicast router timer is not enough as it only\ntakes care of the temporary multicast router states (1 or 3) and not the\npermanent one (2).\n\n[1]\nBUG: KASAN: slab-out-of-bounds in br_multicast_add_router.part.0+0x3f1/0x560\nWrite of size 8 at addr ffff888004a67328 by task ip/384\n[...]\nCall Trace:\n <TASK>\n dump_stack\n---truncated---","state":"PUBLISHED","assigner":"Linux","published_at":"2025-07-09 11:15:26","updated_at":"2026-07-30 06:23:03"},"problem_types":["CWE-416"],"metrics":[{"version":"3.1","source":"nvd@nist.gov","type":"Primary","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/4d3c2a1d4c7c33103f1ddfdbc5cfe1ea4f6d0dcd","name":"https://git.kernel.org/stable/c/4d3c2a1d4c7c33103f1ddfdbc5cfe1ea4f6d0dcd","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/7544f3f5b0b58c396f374d060898b5939da31709","name":"https://git.kernel.org/stable/c/7544f3f5b0b58c396f374d060898b5939da31709","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/bdced577da71b118b6ed4242ebd47f81bf54d406","name":"https://git.kernel.org/stable/c/bdced577da71b118b6ed4242ebd47f81bf54d406","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f05a4f9e959e0fc098046044c650acf897ea52d2","name":"https://git.kernel.org/stable/c/f05a4f9e959e0fc098046044c650acf897ea52d2","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-38248","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-38248","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2796d846d74a18cc6563e96eff8bf28c5e06f912 4d3c2a1d4c7c33103f1ddfdbc5cfe1ea4f6d0dcd git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2796d846d74a18cc6563e96eff8bf28c5e06f912 bdced577da71b118b6ed4242ebd47f81bf54d406 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2796d846d74a18cc6563e96eff8bf28c5e06f912 f05a4f9e959e0fc098046044c650acf897ea52d2 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2796d846d74a18cc6563e96eff8bf28c5e06f912 7544f3f5b0b58c396f374d060898b5939da31709 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 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Vulnrichment"}],"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/bridge/br_multicast.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"4d3c2a1d4c7c33103f1ddfdbc5cfe1ea4f6d0dcd","status":"affected","version":"2796d846d74a18cc6563e96eff8bf28c5e06f912","versionType":"git"},{"lessThan":"bdced577da71b118b6ed4242ebd47f81bf54d406","status":"affected","version":"2796d846d74a18cc6563e96eff8bf28c5e06f912","versionType":"git"},{"lessThan":"f05a4f9e959e0fc098046044c650acf897ea52d2","status":"affected","version":"2796d846d74a18cc6563e96eff8bf28c5e06f912","versionType":"git"},{"lessThan":"7544f3f5b0b58c396f374d060898b5939da31709","status":"affected","version":"2796d846d74a18cc6563e96eff8bf28c5e06f912","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/bridge/br_multicast.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.15"},{"lessThan":"5.15","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.122","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.67","versionType":"semver"},{"lessThanOrEqual":"6.15.*","status":"unaffected","version":"6.15.5","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"6.16","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.122","versionStartIncluding":"5.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.67","versionStartIncluding":"5.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.15.5","versionStartIncluding":"5.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.16","versionStartIncluding":"5.15","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbridge: mcast: Fix use-after-free during router port configuration\n\nThe bridge maintains a global list of ports behind which a multicast\nrouter resides. The list is consulted during forwarding to ensure\nmulticast packets are forwarded to these ports even if the ports are not\nmember in the matching MDB entry.\n\nWhen per-VLAN multicast snooping is enabled, the per-port multicast\ncontext is disabled on each port and the port is removed from the global\nrouter port list:\n\n # ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1\n # ip link add name dummy1 up master br1 type dummy\n # ip link set dev dummy1 type bridge_slave mcast_router 2\n $ bridge -d mdb show | grep router\n router ports on br1: dummy1\n # ip link set dev br1 type bridge mcast_vlan_snooping 1\n $ bridge -d mdb show | grep router\n\nHowever, the port can be re-added to the global list even when per-VLAN\nmulticast snooping is enabled:\n\n # ip link set dev dummy1 type bridge_slave mcast_router 0\n # ip link set dev dummy1 type bridge_slave mcast_router 2\n $ bridge -d mdb show | grep router\n router ports on br1: dummy1\n\nSince commit 4b30ae9adb04 (\"net: bridge: mcast: re-implement\nbr_multicast_{enable, disable}_port functions\"), when per-VLAN multicast\nsnooping is enabled, multicast disablement on a port will disable the\nper-{port, VLAN} multicast contexts and not the per-port one. As a\nresult, a port will remain in the global router port list even after it\nis deleted. This will lead to a use-after-free [1] when the list is\ntraversed (when adding a new port to the list, for example):\n\n # ip link del dev dummy1\n # ip link add name dummy2 up master br1 type dummy\n # ip link set dev dummy2 type bridge_slave mcast_router 2\n\nSimilarly, stale entries can also be found in the per-VLAN router port\nlist. When per-VLAN multicast snooping is disabled, the per-{port, VLAN}\ncontexts are disabled on each port and the port is removed from the\nper-VLAN router port list:\n\n # ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1 mcast_vlan_snooping 1\n # ip link add name dummy1 up master br1 type dummy\n # bridge vlan add vid 2 dev dummy1\n # bridge vlan global set vid 2 dev br1 mcast_snooping 1\n # bridge vlan set vid 2 dev dummy1 mcast_router 2\n $ bridge vlan global show dev br1 vid 2 | grep router\n       router ports: dummy1\n # ip link set dev br1 type bridge mcast_vlan_snooping 0\n $ bridge vlan global show dev br1 vid 2 | grep router\n\nHowever, the port can be re-added to the per-VLAN list even when\nper-VLAN multicast snooping is disabled:\n\n # bridge vlan set vid 2 dev dummy1 mcast_router 0\n # bridge vlan set vid 2 dev dummy1 mcast_router 2\n $ bridge vlan global show dev br1 vid 2 | grep router\n       router ports: dummy1\n\nWhen the VLAN is deleted from the port, the per-{port, VLAN} multicast\ncontext will not be disabled since multicast snooping is not enabled\non the VLAN. As a result, the port will remain in the per-VLAN router\nport list even after it is no longer member in the VLAN. This will lead\nto a use-after-free [2] when the list is traversed (when adding a new\nport to the list, for example):\n\n # ip link add name dummy2 up master br1 type dummy\n # bridge vlan add vid 2 dev dummy2\n # bridge vlan del vid 2 dev dummy1\n # bridge vlan set vid 2 dev dummy2 mcast_router 2\n\nFix these issues by removing the port from the relevant (global or\nper-VLAN) router port list in br_multicast_port_ctx_deinit(). The\nfunction is invoked during port deletion with the per-port multicast\ncontext and during VLAN deletion with the per-{port, VLAN} multicast\ncontext.\n\nNote that deleting the multicast router timer is not enough as it only\ntakes care of the temporary multicast router states (1 or 3) and not the\npermanent one (2).\n\n[1]\nBUG: KASAN: slab-out-of-bounds in br_multicast_add_router.part.0+0x3f1/0x560\nWrite of size 8 at addr ffff888004a67328 by task ip/384\n[...]\nCall Trace:\n <TASK>\n dump_stack\n---truncated---"}],"metrics":[{"cvssV3_1":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"providerMetadata":{"dateUpdated":"2026-07-30T05:52:31.840Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/4d3c2a1d4c7c33103f1ddfdbc5cfe1ea4f6d0dcd"},{"url":"https://git.kernel.org/stable/c/bdced577da71b118b6ed4242ebd47f81bf54d406"},{"url":"https://git.kernel.org/stable/c/f05a4f9e959e0fc098046044c650acf897ea52d2"},{"url":"https://git.kernel.org/stable/c/7544f3f5b0b58c396f374d060898b5939da31709"}],"title":"bridge: mcast: Fix use-after-free during router port configuration","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2025-38248","datePublished":"2025-07-09T10:42:29.133Z","dateReserved":"2025-04-16T04:51:23.997Z","dateUpdated":"2026-07-30T05:52:31.840Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2025-07-09 11:15:26","lastModifiedDate":"2026-07-30 06:23:03","problem_types":["CWE-416"],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9},{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-06-10T20:41:11.360596Z","id":"CVE-2025-38248","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.15.5","matchCriteriaId":"F39C8291-E4C4-42A0-BA95-5A123ED5CAF4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.16:rc1:*:*:*:*:*:*","matchCriteriaId":"6D4894DB-CCFE-4602-B1BF-3960B2E19A01"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.16:rc2:*:*:*:*:*:*","matchCriteriaId":"09709862-E348-4378-8632-5A7813EDDC86"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.16:rc3:*:*:*:*:*:*","matchCriteriaId":"415BF58A-8197-43F5-B3D7-D1D63057A26E"}]}]}]},"legacy_mitre":{"record":{"CveYear":"2025","CveId":"38248","Ordinal":"1","Title":"bridge: mcast: Fix use-after-free during router port configurati","CVE":"CVE-2025-38248","Year":"2025"},"notes":[{"CveYear":"2025","CveId":"38248","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nbridge: mcast: Fix use-after-free during router port configuration\n\nThe bridge maintains a global list of ports behind which a multicast\nrouter resides. The list is consulted during forwarding to ensure\nmulticast packets are forwarded to these ports even if the ports are not\nmember in the matching MDB entry.\n\nWhen per-VLAN multicast snooping is enabled, the per-port multicast\ncontext is disabled on each port and the port is removed from the global\nrouter port list:\n\n # ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1\n # ip link add name dummy1 up master br1 type dummy\n # ip link set dev dummy1 type bridge_slave mcast_router 2\n $ bridge -d mdb show | grep router\n router ports on br1: dummy1\n # ip link set dev br1 type bridge mcast_vlan_snooping 1\n $ bridge -d mdb show | grep router\n\nHowever, the port can be re-added to the global list even when per-VLAN\nmulticast snooping is enabled:\n\n # ip link set dev dummy1 type bridge_slave mcast_router 0\n # ip link set dev dummy1 type bridge_slave mcast_router 2\n $ bridge -d mdb show | grep router\n router ports on br1: dummy1\n\nSince commit 4b30ae9adb04 (\"net: bridge: mcast: re-implement\nbr_multicast_{enable, disable}_port functions\"), when per-VLAN multicast\nsnooping is enabled, multicast disablement on a port will disable the\nper-{port, VLAN} multicast contexts and not the per-port one. As a\nresult, a port will remain in the global router port list even after it\nis deleted. This will lead to a use-after-free [1] when the list is\ntraversed (when adding a new port to the list, for example):\n\n # ip link del dev dummy1\n # ip link add name dummy2 up master br1 type dummy\n # ip link set dev dummy2 type bridge_slave mcast_router 2\n\nSimilarly, stale entries can also be found in the per-VLAN router port\nlist. When per-VLAN multicast snooping is disabled, the per-{port, VLAN}\ncontexts are disabled on each port and the port is removed from the\nper-VLAN router port list:\n\n # ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1 mcast_vlan_snooping 1\n # ip link add name dummy1 up master br1 type dummy\n # bridge vlan add vid 2 dev dummy1\n # bridge vlan global set vid 2 dev br1 mcast_snooping 1\n # bridge vlan set vid 2 dev dummy1 mcast_router 2\n $ bridge vlan global show dev br1 vid 2 | grep router\n       router ports: dummy1\n # ip link set dev br1 type bridge mcast_vlan_snooping 0\n $ bridge vlan global show dev br1 vid 2 | grep router\n\nHowever, the port can be re-added to the per-VLAN list even when\nper-VLAN multicast snooping is disabled:\n\n # bridge vlan set vid 2 dev dummy1 mcast_router 0\n # bridge vlan set vid 2 dev dummy1 mcast_router 2\n $ bridge vlan global show dev br1 vid 2 | grep router\n       router ports: dummy1\n\nWhen the VLAN is deleted from the port, the per-{port, VLAN} multicast\ncontext will not be disabled since multicast snooping is not enabled\non the VLAN. As a result, the port will remain in the per-VLAN router\nport list even after it is no longer member in the VLAN. This will lead\nto a use-after-free [2] when the list is traversed (when adding a new\nport to the list, for example):\n\n # ip link add name dummy2 up master br1 type dummy\n # bridge vlan add vid 2 dev dummy2\n # bridge vlan del vid 2 dev dummy1\n # bridge vlan set vid 2 dev dummy2 mcast_router 2\n\nFix these issues by removing the port from the relevant (global or\nper-VLAN) router port list in br_multicast_port_ctx_deinit(). The\nfunction is invoked during port deletion with the per-port multicast\ncontext and during VLAN deletion with the per-{port, VLAN} multicast\ncontext.\n\nNote that deleting the multicast router timer is not enough as it only\ntakes care of the temporary multicast router states (1 or 3) and not the\npermanent one (2).\n\n[1]\nBUG: KASAN: slab-out-of-bounds in br_multicast_add_router.part.0+0x3f1/0x560\nWrite of size 8 at addr ffff888004a67328 by task ip/384\n[...]\nCall Trace:\n <TASK>\n dump_stack\n---truncated---","Type":"Description","Title":"bridge: mcast: Fix use-after-free during router port configurati"}]}}}