{"cve":"CVE-2021-47266","nvd":{"published":"2024-05-21T15:15:15.213","modified":"2026-06-17T04:17:03.163","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/ipoib: Fix warning caused by destroying non-initial netns\n\nAfter the commit 5ce2dced8e95 (\"RDMA/ipoib: Set rtnl_link_ops for ipoib\ninterfaces\"), if the IPoIB device is moved to non-initial netns,\ndestroying that netns lets the device vanish instead of moving it back to\nthe initial netns, This is happening because default_device_exit() skips\nthe interfaces due to having rtnl_link_ops set.\n\nSteps to reporoduce:\n  ip netns add foo\n  ip link set mlx5_ib0 netns foo\n  ip netns delete foo\n\nWARNING: CPU: 1 PID: 704 at net/core/dev.c:11435 netdev_exit+0x3f/0x50\nModules linked in: xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT\nnf_reject_ipv4 nft_compat nft_counter nft_chain_nat nf_nat nf_conntrack\nnf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink tun d\n fuse\nCPU: 1 PID: 704 Comm: kworker/u64:3 Tainted: G S      W  5.13.0-rc1+ #1\nHardware name: Dell Inc. PowerEdge R630/02C2CP, BIOS 2.1.5 04/11/2016\nWorkqueue: netns cleanup_net\nRIP: 0010:netdev_exit+0x3f/0x50\nCode: 48 8b bb 30 01 00 00 e8 ef 81 b1 ff 48 81 fb c0 3a 54 a1 74 13 48\n8b 83 90 00 00 00 48 81 c3 90 00 00 00 48 39 d8 75 02 5b c3 <0f> 0b 5b\nc3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 0f 1f 44 00\nRSP: 0018:ffffb297079d7e08 EFLAGS: 00010206\nRAX: ffff8eb542c00040 RBX: ffff8eb541333150 RCX: 000000008010000d\nRDX: 000000008010000e RSI: 000000008010000d RDI: ffff8eb440042c00\nRBP: ffffb297079d7e48 R08: 0000000000000001 R09: ffffffff9fdeac00\nR10: ffff8eb5003be000 R11: 0000000000000001 R12: ffffffffa1545620\nR13: ffffffffa1545628 R14: 0000000000000000 R15: ffffffffa1543b20\nFS:  0000000000000000(0000) GS:ffff8ed37fa00000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00005601b5f4c2e8 CR3: 0000001fc8c10002 CR4: 00000000003706e0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n ops_exit_list.isra.9+0x36/0x70\n cleanup_net+0x234/0x390\n process_one_work+0x1cb/0x360\n ? process_one_work+0x360/0x360\n worker_thread+0x30/0x370\n ? process_one_work+0x360/0x360\n kthread+0x116/0x130\n ? kthread_park+0x80/0x80\n ret_from_fork+0x22/0x30\n\nTo avoid the above warning and later on the kernel panic that could happen\non shutdown due to a NULL pointer dereference, make sure to set the\nnetns_refund flag that was introduced by commit 3a5ca857079e (\"can: dev:\nMove device back to init netns on owning netns delete\") to properly\nrestore the IPoIB interfaces to the initial netns.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-476"],"references":["https://git.kernel.org/stable/c/0a672f7d89db2da17ae02733ccc08458be72a6f8","https://git.kernel.org/stable/c/64f1fb6acc2ab95982fc4334f351d7576c26f313","https://git.kernel.org/stable/c/67cf4e447b5e5e9e94996cb6812ae2828e0e0e27","https://git.kernel.org/stable/c/a3e74fb9247cd530dca246699d5eb5a691884d32","https://git.kernel.org/stable/c/0a672f7d89db2da17ae02733ccc08458be72a6f8"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2021-47266","score":0.00232,"percentile":0.14143,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}