In the Linux kernel, the following vulnerability has been resolved: driver: iio: add missing checks on iio_info's callback access Some callbacks from iio_info structure are accessed without any check, so if a driver doesn't implement them trying to access the corresponding sysfs entries produce a kernel oops such as: [ 2203.527791] Unable to handle kernel NULL pointer dereference at virtual address 00000000 when execute [...] [ 2203.783416] Call trace: [ 2203.783429] iio_read_channel_info_avail from dev_attr_show+0x18/0x48 [ 2203.789807] dev_attr_show from sysfs_kf_seq_show+0x90/0x120 [ 2203.794181] sysfs_kf_seq_show from seq_read_iter+0xd0/0x4e4 [ 2203.798555] seq_read_iter from vfs_read+0x238/0x2a0 [ 2203.802236] vfs_read from ksys_read+0xa4/0xd4 [ 2203.805385] ksys_read from ret_fast_syscall+0x0/0x54 [ 2203.809135] Exception stack(0xe0badfa8 to 0xe0badff0) [ 2203.812880] dfa0: 00000003 b6f10f80 00000003 b6eab000 00020000 00000000 [ 2203.819746] dfc0: 00000003 b6f10f80 7ff00000 00000003 00000003 00000000 00020000 00000000 [ 2203.826619] dfe0: b6e1bc88 bed80958 b6e1bc94 b6e1bcb0 [ 2203.830363] Code: bad PC value [ 2203.832695] ---[ end trace 0000000000000000 ]---
| Métrique | Valeur | Interprétation |
|---|---|---|
|
AV (Vecteur d'Attaque)
Attack Vector
|
Local (L)
|
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 |
|
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 |
|
A (Impact Disponibilité)
Availability Impact
|
High (H)
|
Interruption totale du service possible |
driver: iio: add missing checks on iio_info's callback access