{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2023-53556", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-10-04T15:14:15.922Z", "datePublished": "2025-10-04T15:17:01.238Z", "dateUpdated": "2026-08-05T09:14:47.905Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T09:14:47.905Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niavf: Fix use-after-free in free_netdev\n\nWe do netif_napi_add() for all allocated q_vectors[], but potentially\ndo netif_napi_del() for part of them, then kfree q_vectors and leave\ninvalid pointers at dev->napi_list.\n\nReproducer:\n\n [root@host ~]# cat repro.sh\n #!/bin/bash\n\n pf_dbsf=\"0000:41:00.0\"\n vf0_dbsf=\"0000:41:02.0\"\n g_pids=()\n\n function do_set_numvf()\n {\n echo 2 >/sys/bus/pci/devices/${pf_dbsf}/sriov_numvfs\n sleep $((RANDOM%3+1))\n echo 0 >/sys/bus/pci/devices/${pf_dbsf}/sriov_numvfs\n sleep $((RANDOM%3+1))\n }\n\n function do_set_channel()\n {\n local nic=$(ls -1 --indicator-style=none /sys/bus/pci/devices/${vf0_dbsf}/net/)\n [ -z \"$nic\" ] && { sleep $((RANDOM%3)) ; return 1; }\n ifconfig $nic 192.168.18.5 netmask 255.255.255.0\n ifconfig $nic up\n ethtool -L $nic combined 1\n ethtool -L $nic combined 4\n sleep $((RANDOM%3))\n }\n\n function on_exit()\n {\n local pid\n for pid in \"${g_pids[@]}\"; do\n kill -0 \"$pid\" &>/dev/null && kill \"$pid\" &>/dev/null\n done\n g_pids=()\n }\n\n trap \"on_exit; exit\" EXIT\n\n while :; do do_set_numvf ; done &\n g_pids+=($!)\n while :; do do_set_channel ; done &\n g_pids+=($!)\n\n wait\n\nResult:\n\n[ 4093.900222] ==================================================================\n[ 4093.900230] BUG: KASAN: use-after-free in free_netdev+0x308/0x390\n[ 4093.900232] Read of size 8 at addr ffff88b4dc145640 by task repro.sh/6699\n[ 4093.900233]\n[ 4093.900236] CPU: 10 PID: 6699 Comm: repro.sh Kdump: loaded Tainted: G O --------- -t - 4.18.0 #1\n[ 4093.900238] Hardware name: Powerleader PR2008AL/H12DSi-N6, BIOS 2.0 04/09/2021\n[ 4093.900239] Call Trace:\n[ 4093.900244] dump_stack+0x71/0xab\n[ 4093.900249] print_address_description+0x6b/0x290\n[ 4093.900251] ? free_netdev+0x308/0x390\n[ 4093.900252] kasan_report+0x14a/0x2b0\n[ 4093.900254] free_netdev+0x308/0x390\n[ 4093.900261] iavf_remove+0x825/0xd20 [iavf]\n[ 4093.900265] pci_device_remove+0xa8/0x1f0\n[ 4093.900268] device_release_driver_internal+0x1c6/0x460\n[ 4093.900271] pci_stop_bus_device+0x101/0x150\n[ 4093.900273] pci_stop_and_remove_bus_device+0xe/0x20\n[ 4093.900275] pci_iov_remove_virtfn+0x187/0x420\n[ 4093.900277] ? pci_iov_add_virtfn+0xe10/0xe10\n[ 4093.900278] ? pci_get_subsys+0x90/0x90\n[ 4093.900280] sriov_disable+0xed/0x3e0\n[ 4093.900282] ? bus_find_device+0x12d/0x1a0\n[ 4093.900290] i40e_free_vfs+0x754/0x1210 [i40e]\n[ 4093.900298] ? i40e_reset_all_vfs+0x880/0x880 [i40e]\n[ 4093.900299] ? pci_get_device+0x7c/0x90\n[ 4093.900300] ? pci_get_subsys+0x90/0x90\n[ 4093.900306] ? pci_vfs_assigned.part.7+0x144/0x210\n[ 4093.900309] ? __mutex_lock_slowpath+0x10/0x10\n[ 4093.900315] i40e_pci_sriov_configure+0x1fa/0x2e0 [i40e]\n[ 4093.900318] sriov_numvfs_store+0x214/0x290\n[ 4093.900320] ? sriov_totalvfs_show+0x30/0x30\n[ 4093.900321] ? __mutex_lock_slowpath+0x10/0x10\n[ 4093.900323] ? __check_object_size+0x15a/0x350\n[ 4093.900326] kernfs_fop_write+0x280/0x3f0\n[ 4093.900329] vfs_write+0x145/0x440\n[ 4093.900330] ksys_write+0xab/0x160\n[ 4093.900332] ? __ia32_sys_read+0xb0/0xb0\n[ 4093.900334] ? fput_many+0x1a/0x120\n[ 4093.900335] ? filp_close+0xf0/0x130\n[ 4093.900338] do_syscall_64+0xa0/0x370\n[ 4093.900339] ? page_fault+0x8/0x30\n[ 4093.900341] entry_SYSCALL_64_after_hwframe+0x65/0xca\n[ 4093.900357] RIP: 0033:0x7f16ad4d22c0\n[ 4093.900359] Code: 73 01 c3 48 8b 0d d8 cb 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 24 2d 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 fe dd 01 00 48 89 04 24\n[ 4093.900360] RSP: 002b:00007ffd6491b7f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001\n[ 4093.900362] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f16ad4d22c0\n[ 4093.900363] RDX: 0000000000000002 RSI: 0000000001a41408 RDI: 0000000000000001\n[ 4093.900364] RBP: 0000000001a41408 R08: 00007f16ad7a1780 R09: 00007f16ae1f2700\n[ 4093.9003\n---truncated---" } ], "metrics": [ { "cvssV3_1": { "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" }, "scenarios": [ { "lang": "en", "value": "AV:L - The vulnerable state is created through local device-management interfaces — the `ethtool -L` (ETHTOOL_SCHANNELS) ioctl on the VF netdev and sysfs/PCI-unbind driver teardown — and no virtchnl message or received network packet reaches `iavf_free_q_vectors()`. Exploitation therefore requires local access to the system hosting the iavf VF.\nAC:L - The attacker controls both sides of the race described in the commit's own reproducer, issuing the queue-count reconfiguration and driving the VF reset/teardown loop themselves, and can repeat both indefinitely until `iavf_set_channels()` takes its reset-timeout path that lowers `num_active_queues`. Heap grooming of the freed 8192-byte object before `free_netdev()` is likewise under attacker influence.\nPR:L - Reaching `iavf_set_channels()` only needs `ns_capable(net->user_ns, CAP_NET_ADMIN)`, which a container or tenant holds over its own network namespace when an SR-IOV VF is delegated into it — a routine Kubernetes SR-IOV CNI / NFV deployment. No real root in the initial namespace is required to create the NAPI add/del mismatch.\nUI:N - No victim action is needed; the attacker triggers the queue reconfiguration, the resets, and the driver-teardown path themselves in a loop, exactly as in the commit's reproducer script. Stale `napi_struct` entries also persist on a live `netdev->napi_list` after a reinit, so no separate administrator action is required.\nS:U - The use-after-free corrupts kernel heap memory and is exploited entirely within the kernel's own security authority, giving kernel-level control on the same host. No hypervisor, IOMMU, or other security-authority boundary is crossed.\nC:H - The dangling `napi_struct` pointers reference a freed `kmalloc-8k` object that the attacker can reoccupy with sprayed data, and `__netif_napi_del()` reads `napi->state`, `napi->dev_list`, `napi->skb`, `napi->gro_hash[]`, and `napi->thread` from it. Combined with the resulting arbitrary-pointer dereferences, this is leverageable into arbitrary kernel memory disclosure.\nI:H - `__netif_napi_del()` performs `list_del_rcu(&napi->dev_list)` and `hlist_del_init_rcu()` on the freed object, writing to attacker-forged `next`/`prev` pointers — a direct arbitrary-write primitive — plus `kfree_skb()` on controlled `napi->skb`/GRO-hash pointers and `kthread_stop(napi->thread)`. These are sufficient for control-flow hijacking and full privilege escalation.\nA:H - Even without exploitation the use-after-free corrupts `netdev->napi_list` and reliably oopses in `free_netdev()`, as shown by the KASAN splat in the commit message. Any list-walk consumer (`free_netdev()`, `netif_set_threaded()`, `__netpoll_setup()`) can panic the kernel." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/ethernet/intel/iavf/iavf_main.c" ], "versions": [ { "version": "5eae00c57f5e42bf201023471917da213c4946d6", "lessThan": "17046107ca15d7571551539d94e76aba2bf71fd3", "status": "affected", "versionType": "git" }, { "version": "5eae00c57f5e42bf201023471917da213c4946d6", "lessThan": "a4635f190f332304db4a49e827ece790b804b5db", "status": "affected", "versionType": "git" }, { "version": "5eae00c57f5e42bf201023471917da213c4946d6", "lessThan": "345c44e18cc10cded85cb9134830e1684495c866", "status": "affected", "versionType": "git" }, { "version": "5eae00c57f5e42bf201023471917da213c4946d6", "lessThan": "ca12b98e04b5d1902ac08fe826d3500cb4b6e891", "status": "affected", "versionType": "git" }, { "version": "5eae00c57f5e42bf201023471917da213c4946d6", "lessThan": "8d781a9c53034813c3194b7d94409c7d24ac73eb", "status": "affected", "versionType": "git" }, { "version": "5eae00c57f5e42bf201023471917da213c4946d6", "lessThan": "5f4fa1672d98fe99d2297b03add35346f1685d6b", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/ethernet/intel/iavf/iavf_main.c" ], "versions": [ { "version": "3.14", "status": "affected" }, { "version": "0", "lessThan": "3.14", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.251", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.188", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.123", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.42", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.4.7", "lessThanOrEqual": "6.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.5", "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": "3.14", "versionEndExcluding": "5.4.251" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "5.10.188" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "5.15.123" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "6.1.42" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "6.4.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "6.5" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/17046107ca15d7571551539d94e76aba2bf71fd3" }, { "url": "https://git.kernel.org/stable/c/a4635f190f332304db4a49e827ece790b804b5db" }, { "url": "https://git.kernel.org/stable/c/345c44e18cc10cded85cb9134830e1684495c866" }, { "url": "https://git.kernel.org/stable/c/ca12b98e04b5d1902ac08fe826d3500cb4b6e891" }, { "url": "https://git.kernel.org/stable/c/8d781a9c53034813c3194b7d94409c7d24ac73eb" }, { "url": "https://git.kernel.org/stable/c/5f4fa1672d98fe99d2297b03add35346f1685d6b" } ], "title": "iavf: Fix use-after-free in free_netdev", "x_generator": { "engine": "bippy-1.2.0" } } } }