{"cve":"CVE-2021-47589","nvd":{"published":"2024-06-19T15:15:53.490","modified":"2026-06-17T04:17:49.590","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nigbvf: fix double free in `igbvf_probe`\n\nIn `igbvf_probe`, if register_netdev() fails, the program will go to\nlabel err_hw_init, and then to label err_ioremap. In free_netdev() which\nis just below label err_ioremap, there is `list_for_each_entry_safe` and\n`netif_napi_del` which aims to delete all entries in `dev->napi_list`.\nThe program has added an entry `adapter->rx_ring->napi` which is added by\n`netif_napi_add` in igbvf_alloc_queues(). However, adapter->rx_ring has\nbeen freed below label err_hw_init. So this a UAF.\n\nIn terms of how to patch the problem, we can refer to igbvf_remove() and\ndelete the entry before `adapter->rx_ring`.\n\nThe KASAN logs are as follows:\n\n[   35.126075] BUG: KASAN: use-after-free in free_netdev+0x1fd/0x450\n[   35.127170] Read of size 8 at addr ffff88810126d990 by task modprobe/366\n[   35.128360]\n[   35.128643] CPU: 1 PID: 366 Comm: modprobe Not tainted 5.15.0-rc2+ #14\n[   35.129789] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014\n[   35.131749] Call Trace:\n[   35.132199]  dump_stack_lvl+0x59/0x7b\n[   35.132865]  print_address_description+0x7c/0x3b0\n[   35.133707]  ? free_netdev+0x1fd/0x450\n[   35.134378]  __kasan_report+0x160/0x1c0\n[   35.135063]  ? free_netdev+0x1fd/0x450\n[   35.135738]  kasan_report+0x4b/0x70\n[   35.136367]  free_netdev+0x1fd/0x450\n[   35.137006]  igbvf_probe+0x121d/0x1a10 [igbvf]\n[   35.137808]  ? igbvf_vlan_rx_add_vid+0x100/0x100 [igbvf]\n[   35.138751]  local_pci_probe+0x13c/0x1f0\n[   35.139461]  pci_device_probe+0x37e/0x6c0\n[   35.165526]\n[   35.165806] Allocated by task 366:\n[   35.166414]  ____kasan_kmalloc+0xc4/0xf0\n[   35.167117]  foo_kmem_cache_alloc_trace+0x3c/0x50 [igbvf]\n[   35.168078]  igbvf_probe+0x9c5/0x1a10 [igbvf]\n[   35.168866]  local_pci_probe+0x13c/0x1f0\n[   35.169565]  pci_device_probe+0x37e/0x6c0\n[   35.179713]\n[   35.179993] Freed by task 366:\n[   35.180539]  kasan_set_track+0x4c/0x80\n[   35.181211]  kasan_set_free_info+0x1f/0x40\n[   35.181942]  ____kasan_slab_free+0x103/0x140\n[   35.182703]  kfree+0xe3/0x250\n[   35.183239]  igbvf_probe+0x1173/0x1a10 [igbvf]\n[   35.184040]  local_pci_probe+0x13c/0x1f0","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-415"],"references":["https://git.kernel.org/stable/c/74a16e062b23332d8db017ff4a41e16279c44411","https://git.kernel.org/stable/c/79d9b092035dcdbe636b70433149df9cc6db1e49","https://git.kernel.org/stable/c/8addba6cab94ce01686ea2e80ed1530f9dc33a9a","https://git.kernel.org/stable/c/8d0c927a9fb2b4065230936b77b54f857a3754fc","https://git.kernel.org/stable/c/944b8be08131f5faf2cd2440aa1c24a39a163a54"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:52:00.836172422+00:00"},"epss":{"cve":"CVE-2021-47589","score":0.00259,"percentile":0.17613,"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."]}