{"cve":"CVE-2025-21682","nvd":{"published":"2025-01-31T12:15:29.363","modified":"2026-10-15T02:17:26.477","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\neth: bnxt: always recalculate features after XDP clearing, fix null-deref\n\nRecalculate features when XDP is detached.\n\nBefore:\n  # ip li set dev eth0 xdp obj xdp_dummy.bpf.o sec xdp\n  # ip li set dev eth0 xdp off\n  # ethtool -k eth0 | grep gro\n  rx-gro-hw: off [requested on]\n\nAfter:\n  # ip li set dev eth0 xdp obj xdp_dummy.bpf.o sec xdp\n  # ip li set dev eth0 xdp off\n  # ethtool -k eth0 | grep gro\n  rx-gro-hw: on\n\nThe fact that HW-GRO doesn't get re-enabled automatically is just\na minor annoyance. The real issue is that the features will randomly\ncome back during another reconfiguration which just happens to invoke\nnetdev_update_features(). The driver doesn't handle reconfiguring\ntwo things at a time very robustly.\n\nStarting with commit 98ba1d931f61 (\"bnxt_en: Fix RSS logic in\n__bnxt_reserve_rings()\") we only reconfigure the RSS hash table\nif the \"effective\" number of Rx rings has changed. If HW-GRO is\nenabled \"effective\" number of rings is 2x what user sees.\nSo if we are in the bad state, with HW-GRO re-enablement \"pending\"\nafter XDP off, and we lower the rings by / 2 - the HW-GRO rings\ndoing 2x and the ethtool -L doing / 2 may cancel each other out,\nand the:\n\n  if (old_rx_rings != bp->hw_resc.resv_rx_rings &&\n\ncondition in __bnxt_reserve_rings() will be false.\nThe RSS map won't get updated, and we'll crash with:\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000168\n  RIP: 0010:__bnxt_hwrm_vnic_set_rss+0x13a/0x1a0\n    bnxt_hwrm_vnic_rss_cfg_p5+0x47/0x180\n    __bnxt_setup_vnic_p5+0x58/0x110\n    bnxt_init_nic+0xb72/0xf50\n    __bnxt_open_nic+0x40d/0xab0\n    bnxt_open_nic+0x2b/0x60\n    ethtool_set_channels+0x18c/0x1d0\n\nAs we try to access a freed ring.\n\nThe issue is present since XDP support was added, really, but\nprior to commit 98ba1d931f61 (\"bnxt_en: Fix RSS logic in\n__bnxt_reserve_rings()\") it wasn't causing major issues.","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/076a694a42ae3f0466bc6e4126050eeb7b7d299a","https://git.kernel.org/stable/c/08831a894d18abfaabb5bbde7c2069a7fb41dd93","https://git.kernel.org/stable/c/90336fc3d6f5e716ac39a9ddbbde453e23a5aa65","https://git.kernel.org/stable/c/f0aa6a37a3dbb40b272df5fc6db93c114688adcd","https://cert-portal.siemens.com/productcert/html/ssa-019113.html"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:58:41.599736885+00:00"},"epss":{"cve":"CVE-2025-21682","score":0.00233,"percentile":0.14074,"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."]}