{"id":"CVE-2026-99172","revision":"b5c0185c421f4e63a1bb556ecd4b9e64","records":[{"revision":"b5c0185c421f4e63a1bb556ecd4b9e64","observedAt":"2026-10-28T11:27:43.363+00:00","statement":{"source":"cve-program","id":"CVE-2026-99172","aliases":[],"title":"ipc: drop the mqueue mount with kern_unmount() on setup failure","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipc: drop the mqueue mount with kern_unmount() on setup failure\n\nmq_init_ns() creates the mqueue mount with fc_mount_longterm(), so its\n->mnt_ns is MNT_NS_INTERNAL. When setting up the mqueue or ipc sysctls\nor msg_init_ns() fails afterwards, create_ipc_ns() drops it with a plain\nmntput(). With ->mnt_ns set that takes the fast path of\nmntput_no_expire(). The count drops to zero and nothing ever kills the\nmount, so the mount and the mqueue superblock are leaked.\n\nCommit dc55e35f9e81 (\"ipc: Store mqueue sysctls in the ipc namespace\")\nadded the first failure path after mq_init_ns() and never dropped the\nmount. Commit 7229d74e5e8c (\"ipc: create_ipc_ns: drop mqueue mount on\nsysctl setup failure\") tried to fix that with a mntput() but that\ndoesn't help for a long-term mount.\n\nUse kern_unmount(). free_ipc() open-codes the same thing for a namespace\nthat made it.","state":0,"publishedAt":"2026-10-28T10:35:27.245+00:00","modifiedAt":"2026-10-28T10:35:27.245+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"ipc/namespace.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"dc55e35f9e810f23dd69cfdc91a3d636023f57a2\",\n                            \"lessThan\": \"c0620b648321fff654173d238d4a85298ea16d05\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"dc55e35f9e810f23dd69cfdc91a3d636023f57a2\",\n                            \"lessThan\": \"f0e48172a59e517e613b73f73cc35f24fd123aeb\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"ipc/namespace.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"5.19\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"5.19\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.13\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/c0620b648321fff654173d238d4a85298ea16d05","https://git.kernel.org/stable/c/f0e48172a59e517e613b73f73cc35f24fd123aeb"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-99172","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-99172","identifiers":["CVE-2026-99172"]},"retained":false,"historicalAffected":[]}],"coverage":[]}