In the Linux kernel, the following vulnerability has been resolved: drm/i915/dsc: Fix the macro that calculates DSCC_/DSCA_ PPS reg address Commit bd077259d0a9 ("drm/i915/vdsc: Add function to read any PPS register") defines a new macro to calculate the DSC PPS register addresses with PPS number as an input. This macro correctly calculates the addresses till PPS 11 since the addresses increment by 4. So in that case the following macro works correctly to give correct register address: _MMIO(_DSCA_PPS_0 + (pps) * 4) However after PPS 11, the register address for PPS 12 increments by 12 because of RC Buffer memory allocation in between. Because of this discontinuity in the address space, the macro calculates wrong addresses for PPS 12 - 16 resulting into incorrect DSC PPS parameter value read/writes causing DSC corruption. This fixes it by correcting this macro to add the offset of 12 for PPS >=12. v3: Add correct paranthesis for pps argument (Jani Nikula) (cherry picked from commit 6074be620c31dc2ae11af96a1a5ea95580976fb5)
| Métrique | Valeur | Interprétation |
|---|---|---|
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AV (Vecteur d'Attaque)
Attack Vector
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Local (L)
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Exploit nécessite un accès local au système |
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AC (Complexité d'Attaque)
Attack Complexity
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Low (L)
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Peu de conditions requises pour exploiter |
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PR (Privilèges Requis)
Privileges Required
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Low (L)
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Authentifié avec compte utilisateur basique |
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UI (Interaction Utilisateur)
User Interaction
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None (N)
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Aucune interaction utilisateur nécessaire |
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S (Périmètre)
Scope
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Unchanged (U)
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Impact reste dans le périmètre du composant compromis |
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C (Impact Confidentialité)
Confidentiality Impact
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None (N)
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Aucune divulgation d'informations |
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I (Impact Intégrité)
Integrity Impact
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None (N)
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Aucune modification de données possible |
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A (Impact Disponibilité)
Availability Impact
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High (H)
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Interruption totale du service possible |
drm/i915/dsc: Fix the macro that calculates DSCC_/DSCA_ PPS reg address