CVE-2025-21682

{"id": "CVE-2025-21682", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2025-01-31T12:15:29.363", "references": [{"url": "https://git.kernel.org/stable/c/08831a894d18abfaabb5bbde7c2069a7fb41dd93", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/f0aa6a37a3dbb40b272df5fc6db93c114688adcd", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-476"}]}], "descriptions": [{"lang": "en", "value": "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."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: eth: bnxt: siempre recalcula las caracter\u00edsticas despu\u00e9s de borrar XDP, corrige null-deref Recalcula las caracter\u00edsticas cuando se desconecta XDP. Antes: # ip li set dev eth0 xdp obj xdp_dummy.bpf.o sec xdp # ip li set dev eth0 xdp off # ethtool -k eth0 | grep gro rx-gro-hw: off [solicitado el] Despu\u00e9s: # ip li set dev eth0 xdp obj xdp_dummy.bpf.o sec xdp # ip li set dev eth0 xdp off # ethtool -k eth0 | grep gro rx-gro-hw: on El hecho de que HW-GRO no se vuelva a habilitar autom\u00e1ticamente es solo una molestia menor. El problema real es que las funciones volver\u00e1n de forma aleatoria durante otra reconfiguraci\u00f3n que invoca netdev_update_features(). El controlador no gestiona la reconfiguraci\u00f3n de dos cosas a la vez de forma muy robusta. A partir de el commit 98ba1d931f61 (\"bnxt_en: Fix RSS logic in __bnxt_reserve_rings()\"), solo reconfiguramos la tabla hash RSS si el n\u00famero \"efectivo\" de anillos Rx ha cambiado. Si HW-GRO est\u00e1 habilitado, el n\u00famero \"efectivo\" de anillos es el doble de lo que ve el usuario. Entonces, si estamos en un mal estado, con la rehabilitaci\u00f3n de HW-GRO \"pendiente\" despu\u00e9s de desactivar XDP, y reducimos los anillos en / 2, los anillos de HW-GRO haciendo 2x y ethtool -L haciendo / 2 pueden cancelarse entre s\u00ed, y la condici\u00f3n: if (old_rx_rings != bp->hw_resc.resv_rx_rings && en __bnxt_reserve_rings() ser\u00e1 falsa. El mapa RSS no se actualizar\u00e1 y nos bloquearemos con: ERROR: desreferencia de puntero NULL del kernel, direcci\u00f3n: 0000000000000168 RIP: 0010:__bnxt_hwrm_vnic_set_rss+0x13a/0x1a0 bnxt_hwrm_vnic_rss_cfg_p5+0x47/0x180 __bnxt_setup_vnic_p5+0x58/0x110 bnxt_init_nic+0xb72/0xf50 __bnxt_open_nic+0x40d/0xab0 bnxt_open_nic+0x2b/0x60 ethtool_set_channels+0x18c/0x1d0 Cuando intentamos acceder a un anillo liberado, el problema est\u00e1 presente desde que se agreg\u00f3 la compatibilidad con XDP, pero antes de el commit 98ba1d931f61 (\"bnxt_en: Fix RSS logic in __bnxt_reserve_rings()\") no causaba problemas importantes."}], "lastModified": "2025-02-04T15:25:48.707", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D85A4303-7769-4ADC-A840-D2F38DB827CE", "versionEndExcluding": "6.12.11", "versionStartIncluding": "4.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "62567B3C-6CEE-46D0-BC2E-B3717FBF7D13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5A073481-106D-4B15-B4C7-FB0213B8E1D4"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "DE491969-75AE-4A6B-9A58-8FC5AF98798F"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "93C0660D-7FB8-4FBA-892A-B064BA71E49E"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "034C36A6-C481-41F3-AE9A-D116E5BE6895"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc6:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8AF9DC49-2085-4FFB-A7E3-73DFAFECC7F2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc7:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5DFCDFB8-4FD0-465A-9076-D813D78FE51B"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}