{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-21884", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-12-29T08:45:45.782Z", "datePublished": "2025-03-27T14:57:12.486Z", "dateUpdated": "2026-05-11T21:08:23.279Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T21:08:23.279Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: better track kernel sockets lifetime\n\nWhile kernel sockets are dismantled during pernet_operations->exit(),\ntheir freeing can be delayed by any tx packets still held in qdisc\nor device queues, due to skb_set_owner_w() prior calls.\n\nThis then trigger the following warning from ref_tracker_dir_exit() [1]\n\nTo fix this, make sure that kernel sockets own a reference on net->passive.\n\nAdd sk_net_refcnt_upgrade() helper, used whenever a kernel socket\nis converted to a refcounted one.\n\n[1]\n\n[ 136.263918][ T35] ref_tracker: net notrefcnt@ffff8880638f01e0 has 1/2 users at\n[ 136.263918][ T35] sk_alloc+0x2b3/0x370\n[ 136.263918][ T35] inet6_create+0x6ce/0x10f0\n[ 136.263918][ T35] __sock_create+0x4c0/0xa30\n[ 136.263918][ T35] inet_ctl_sock_create+0xc2/0x250\n[ 136.263918][ T35] igmp6_net_init+0x39/0x390\n[ 136.263918][ T35] ops_init+0x31e/0x590\n[ 136.263918][ T35] setup_net+0x287/0x9e0\n[ 136.263918][ T35] copy_net_ns+0x33f/0x570\n[ 136.263918][ T35] create_new_namespaces+0x425/0x7b0\n[ 136.263918][ T35] unshare_nsproxy_namespaces+0x124/0x180\n[ 136.263918][ T35] ksys_unshare+0x57d/0xa70\n[ 136.263918][ T35] __x64_sys_unshare+0x38/0x40\n[ 136.263918][ T35] do_syscall_64+0xf3/0x230\n[ 136.263918][ T35] entry_SYSCALL_64_after_hwframe+0x77/0x7f\n[ 136.263918][ T35]\n[ 136.343488][ T35] ref_tracker: net notrefcnt@ffff8880638f01e0 has 1/2 users at\n[ 136.343488][ T35] sk_alloc+0x2b3/0x370\n[ 136.343488][ T35] inet6_create+0x6ce/0x10f0\n[ 136.343488][ T35] __sock_create+0x4c0/0xa30\n[ 136.343488][ T35] inet_ctl_sock_create+0xc2/0x250\n[ 136.343488][ T35] ndisc_net_init+0xa7/0x2b0\n[ 136.343488][ T35] ops_init+0x31e/0x590\n[ 136.343488][ T35] setup_net+0x287/0x9e0\n[ 136.343488][ T35] copy_net_ns+0x33f/0x570\n[ 136.343488][ T35] create_new_namespaces+0x425/0x7b0\n[ 136.343488][ T35] unshare_nsproxy_namespaces+0x124/0x180\n[ 136.343488][ T35] ksys_unshare+0x57d/0xa70\n[ 136.343488][ T35] __x64_sys_unshare+0x38/0x40\n[ 136.343488][ T35] do_syscall_64+0xf3/0x230\n[ 136.343488][ T35] entry_SYSCALL_64_after_hwframe+0x77/0x7f" } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "include/net/sock.h", "net/core/sock.c", "net/mptcp/subflow.c", "net/netlink/af_netlink.c", "net/rds/tcp.c", "net/smc/af_smc.c", "net/sunrpc/svcsock.c", "net/sunrpc/xprtsock.c" ], "versions": [ { "version": "0cafd77dcd032d1687efaba5598cf07bce85997f", "lessThan": "2668e038800b946d269f96ec1b258c01930a242c", "status": "affected", "versionType": "git" }, { "version": "0cafd77dcd032d1687efaba5598cf07bce85997f", "lessThan": "4ceb0bd4ffd009821b585ce6a8033b12b59fb5fb", "status": "affected", "versionType": "git" }, { "version": "0cafd77dcd032d1687efaba5598cf07bce85997f", "lessThan": "c31a732fac46b00b95b78fcc9c37cb48dd6f2e0c", "status": "affected", "versionType": "git" }, { "version": "0cafd77dcd032d1687efaba5598cf07bce85997f", "lessThan": "5c70eb5c593d64d93b178905da215a9fd288a4b5", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "include/net/sock.h", "net/core/sock.c", "net/mptcp/subflow.c", "net/netlink/af_netlink.c", "net/rds/tcp.c", "net/smc/af_smc.c", "net/sunrpc/svcsock.c", "net/sunrpc/xprtsock.c" ], "versions": [ { "version": "6.2", "status": "affected" }, { "version": "0", "lessThan": "6.2", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.103", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.43", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.13.6", "lessThanOrEqual": "6.13.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.14", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.6.103" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.12.43" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.13.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.14" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/2668e038800b946d269f96ec1b258c01930a242c" }, { "url": "https://git.kernel.org/stable/c/4ceb0bd4ffd009821b585ce6a8033b12b59fb5fb" }, { "url": "https://git.kernel.org/stable/c/c31a732fac46b00b95b78fcc9c37cb48dd6f2e0c" }, { "url": "https://git.kernel.org/stable/c/5c70eb5c593d64d93b178905da215a9fd288a4b5" } ], "title": "net: better track kernel sockets lifetime", "x_generator": { "engine": "bippy-1.2.0" } } } }