In the Linux kernel, the following vulnerability has been resolved: net: mscc: ocelot: fix incorrect IFH SRC_PORT field in ocelot_ifh_set_basic() Packets injected by the CPU should have a SRC_PORT field equal to the CPU port module index in the Analyzer block (ocelot->num_phys_ports). The blamed commit copied the ocelot_ifh_set_basic() call incorrectly from ocelot_xmit_common() in net/dsa/tag_ocelot.c. Instead of calling with "x", it calls with BIT_ULL(x), but the field is not a port mask, but rather a single port index. [ side note: this is the technical debt of code duplication :( ] The error used to be silent and doesn't appear to have other user-visible manifestations, but with new changes in the packing library, it now fails loudly as follows: ------------[ cut here ]------------ Cannot store 0x40 inside bits 46-43 - will truncate sja1105 spi2.0: xmit timed out WARNING: CPU: 1 PID: 102 at lib/packing.c:98 __pack+0x90/0x198 sja1105 spi2.0: timed out polling for tstamp CPU: 1 UID: 0 PID: 102 Comm: felix_xmit Tainted: G W N 6.13.0-rc1-00372-gf706b85d972d-dirty #2605 Call trace: __pack+0x90/0x198 (P) __pack+0x90/0x198 (L) packing+0x78/0x98 ocelot_ifh_set_basic+0x260/0x368 ocelot_port_inject_frame+0xa8/0x250 felix_port_deferred_xmit+0x14c/0x258 kthread_worker_fn+0x134/0x350 kthread+0x114/0x138 The code path pertains to the ocelot switchdev driver and to the felix secondary DSA tag protocol, ocelot-8021q. Here seen with ocelot-8021q. The messenger (packing) is not really to blame, so fix the original commit instead.
| Métrique | Valeur | Interprétation |
|---|---|---|
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AV (Vecteur d'Attaque)
Attack Vector
|
Local (L)
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Exploit nécessite un accès local au système |
|
AC (Complexité d'Attaque)
Attack Complexity
|
Low (L)
|
Peu de conditions requises pour exploiter |
|
PR (Privilèges Requis)
Privileges Required
|
Low (L)
|
Authentifié avec compte utilisateur basique |
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UI (Interaction Utilisateur)
User Interaction
|
None (N)
|
Aucune interaction utilisateur nécessaire |
|
S (Périmètre)
Scope
|
Unchanged (U)
|
Impact reste dans le périmètre du composant compromis |
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C (Impact Confidentialité)
Confidentiality Impact
|
None (N)
|
Aucune divulgation d'informations |
|
I (Impact Intégrité)
Integrity Impact
|
None (N)
|
Aucune modification de données possible |
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A (Impact Disponibilité)
Availability Impact
|
High (H)
|
Interruption totale du service possible |
net: mscc: ocelot: fix incorrect IFH SRC_PORT field in ocelot_ifh_set_basic()