{"id":"CVE-2026-23310","summary":"bpf/bonding: reject vlan+srcmac xmit_hash_policy change when XDP is loaded","details":"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-\u003exdp_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.","modified":"2026-04-14T03:47:30.025500Z","published":"2026-03-25T10:27:05.943Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23310.json","cna_assigner":"Linux"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/0ace8027e41f6f094ef6c1aca42d2ed6cd7af54e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/479d589b40b836442bbdadc3fdb37f001bb67f26"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5c262bd0e39320a6d6c8277cb8349ce21c01b8c1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d36ad7e126c6a0c5f699583309ccc37e3a3263ea"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e85fa809e507b9d8eff4840888b8c727e4e8448c"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23310.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23310"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"39a0876d595bd7c7512782dfcce0ee66f65bf221"},{"fixed":"5c262bd0e39320a6d6c8277cb8349ce21c01b8c1"},{"fixed":"d36ad7e126c6a0c5f699583309ccc37e3a3263ea"},{"fixed":"0ace8027e41f6f094ef6c1aca42d2ed6cd7af54e"},{"fixed":"e85fa809e507b9d8eff4840888b8c727e4e8448c"},{"fixed":"479d589b40b836442bbdadc3fdb37f001bb67f26"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-23310.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.15.0"},{"fixed":"6.6.130"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.77"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.17"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"6.19.7"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-23310.json"}}],"schema_version":"1.7.5"}