In the Linux kernel, the following vulnerability has been resolved: perf/core: Bail out early if the request AUX area is out of bound When perf-record with a large AUX area, e.g 4GB, it fails with: #perf record -C 0 -m ,4G -e arm_spe_0// -- sleep 1 failed to mmap with 12 (Cannot allocate memory) and it reveals a WARNING with __alloc_pages(): ------------[ cut here ]------------ WARNING: CPU: 44 PID: 17573 at mm/page_alloc.c:5568 __alloc_pages+0x1ec/0x248 Call trace: __alloc_pages+0x1ec/0x248 __kmalloc_large_node+0xc0/0x1f8 __kmalloc_node+0x134/0x1e8 rb_alloc_aux+0xe0/0x298 perf_mmap+0x440/0x660 mmap_region+0x308/0x8a8 do_mmap+0x3c0/0x528 vm_mmap_pgoff+0xf4/0x1b8 ksys_mmap_pgoff+0x18c/0x218 __arm64_sys_mmap+0x38/0x58 invoke_syscall+0x50/0x128 el0_svc_common.constprop.0+0x58/0x188 do_el0_svc+0x34/0x50 el0_svc+0x34/0x108 el0t_64_sync_handler+0xb8/0xc0 el0t_64_sync+0x1a4/0x1a8 'rb->aux_pages' allocated by kcalloc() is a pointer array which is used to maintains AUX trace pages. The allocated page for this array is physically contiguous (and virtually contiguous) with an order of 0..MAX_ORDER. If the size of pointer array crosses the limitation set by MAX_ORDER, it reveals a WARNING. So bail out early with -ENOMEM if the request AUX area is out of bound, e.g.: #perf record -C 0 -m ,4G -e arm_spe_0// -- sleep 1 failed to mmap with 12 (Cannot allocate memory)
| 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 |
|
C (Impact Confidentialité)
Confidentiality Impact
|
High (H)
|
Divulgation totale d'informations |
|
I (Impact Intégrité)
Integrity Impact
|
High (H)
|
Modification totale des données possible |
|
A (Impact Disponibilité)
Availability Impact
|
High (H)
|
Interruption totale du service possible |