{"cve":"CVE-2026-23310","nvd":{"published":"2026-03-25T11:16:27.160","modified":"2026-10-15T02:18:48.810","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf/bonding: reject vlan+srcmac xmit_hash_policy change when XDP is loaded\n\nbond_option_mode_set() already rejects mode changes that would make a\nloaded XDP program incompatible via bond_xdp_check().  However,\nbond_option_xmit_hash_policy_set() has no such guard.\n\nFor 802.3ad and balance-xor modes, bond_xdp_check() returns false when\nxmit_hash_policy is vlan+srcmac, because the 802.1q payload is usually\nabsent due to hardware offload.  This means a user can:\n\n1. Attach a native XDP program to a bond in 802.3ad/balance-xor mode\n   with a compatible xmit_hash_policy (e.g. layer2+3).\n2. Change xmit_hash_policy to vlan+srcmac while XDP remains loaded.\n\nThis leaves bond->xdp_prog set but bond_xdp_check() now returning false\nfor the same device.  When the bond is later destroyed, dev_xdp_uninstall()\ncalls bond_xdp_set(dev, NULL, NULL) to remove the program, which hits\nthe bond_xdp_check() guard and returns -EOPNOTSUPP, triggering:\n\nWARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL))\n\nFix this by rejecting xmit_hash_policy changes to vlan+srcmac when an\nXDP program is loaded on a bond in 802.3ad or balance-xor mode.\n\ncommit 39a0876d595b (\"net, bonding: Disallow vlan+srcmac with XDP\")\nintroduced bond_xdp_check() which returns false for 802.3ad/balance-xor\nmodes when xmit_hash_policy is vlan+srcmac.  The check was wired into\nbond_xdp_set() to reject XDP attachment with an incompatible policy, but\nthe symmetric path -- preventing xmit_hash_policy from being changed to an\nincompatible value after XDP is already loaded -- was left unguarded in\nbond_option_xmit_hash_policy_set().\n\nNote:\ncommit 094ee6017ea0 (\"bonding: check xdp prog when set bond mode\")\nlater added a similar guard to bond_option_mode_set(), but\nbond_option_xmit_hash_policy_set() remained unprotected.","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":[],"references":["https://git.kernel.org/stable/c/0a80e6ecaf669c77260b44254f4a84d76bf83e89","https://git.kernel.org/stable/c/0ace8027e41f6f094ef6c1aca42d2ed6cd7af54e","https://git.kernel.org/stable/c/479d589b40b836442bbdadc3fdb37f001bb67f26","https://git.kernel.org/stable/c/5c262bd0e39320a6d6c8277cb8349ce21c01b8c1","https://git.kernel.org/stable/c/d36ad7e126c6a0c5f699583309ccc37e3a3263ea"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:26:19.218427112+00:00"},"epss":{"cve":"CVE-2026-23310","score":0.00127,"percentile":0.02378,"date":"2026-10-25"},"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."]}