In the Linux kernel, the following vulnerability has been resolved: eeprom: ee1004: limit i2c reads to I2C_SMBUS_BLOCK_MAX Commit effa453168a7 ("i2c: i801: Don't silently correct invalid transfer size") revealed that ee1004_eeprom_read() did not properly limit how many bytes to read at once. In particular, i2c_smbus_read_i2c_block_data_or_emulated() takes the length to read as an u8. If count == 256 after taking into account the offset and page boundary, the cast to u8 overflows. And this is common when user space tries to read the entire EEPROM at once. To fix it, limit each read to I2C_SMBUS_BLOCK_MAX (32) bytes, already the maximum length i2c_smbus_read_i2c_block_data_or_emulated() allows.
| 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
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None (N)
|
Aucune modification de données possible |
|
A (Impact Disponibilité)
Availability Impact
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High (H)
|
Interruption totale du service possible |
eeprom: ee1004: limit i2c reads to I2C_SMBUS_BLOCK_MAX