In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix command bitmask initialization Command bitmask have a dedicated bit for MANAGE_PAGES command, this bit isn't Initialize during command bitmask Initialization, only during MANAGE_PAGES. In addition, mlx5_cmd_trigger_completions() is trying to trigger completion for MANAGE_PAGES command as well. Hence, in case health error occurred before any MANAGE_PAGES command have been invoke (for example, during mlx5_enable_hca()), mlx5_cmd_trigger_completions() will try to trigger completion for MANAGE_PAGES command, which will result in null-ptr-deref error.[1] Fix it by Initialize command bitmask correctly. While at it, re-write the code for better understanding. [1] BUG: KASAN: null-ptr-deref in mlx5_cmd_trigger_completions+0x1db/0x600 [mlx5_core] Write of size 4 at addr 0000000000000214 by task kworker/u96:2/12078 CPU: 10 PID: 12078 Comm: kworker/u96:2 Not tainted 6.9.0-rc2_for_upstream_debug_2024_04_07_19_01 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 Workqueue: mlx5_health0000:08:00.0 mlx5_fw_fatal_reporter_err_work [mlx5_core] Call Trace: <TASK> dump_stack_lvl+0x7e/0xc0 kasan_report+0xb9/0xf0 kasan_check_range+0xec/0x190 mlx5_cmd_trigger_completions+0x1db/0x600 [mlx5_core] mlx5_cmd_flush+0x94/0x240 [mlx5_core] enter_error_state+0x6c/0xd0 [mlx5_core] mlx5_fw_fatal_reporter_err_work+0xf3/0x480 [mlx5_core] process_one_work+0x787/0x1490 ? lockdep_hardirqs_on_prepare+0x400/0x400 ? pwq_dec_nr_in_flight+0xda0/0xda0 ? assign_work+0x168/0x240 worker_thread+0x586/0xd30 ? rescuer_thread+0xae0/0xae0 kthread+0x2df/0x3b0 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x2d/0x70 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork_asm+0x11/0x20 </TASK>
| 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
|
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 |
net/mlx5: Fix command bitmask initialization