In the Linux kernel, the following vulnerability has been resolved: iavf: Fix hang during reboot/shutdown Recent commit 974578017fc1 ("iavf: Add waiting so the port is initialized in remove") adds a wait-loop at the beginning of iavf_remove() to ensure that port initialization is finished prior unregistering net device. This causes a regression in reboot/shutdown scenario because in this case callback iavf_shutdown() is called and this callback detaches the device, makes it down if it is running and sets its state to __IAVF_REMOVE. Later shutdown callback of associated PF driver (e.g. ice_shutdown) is called. That callback calls among other things sriov_disable() that calls indirectly iavf_remove() (see stack trace below). As the adapter state is already __IAVF_REMOVE then the mentioned loop is end-less and shutdown process hangs. The patch fixes this by checking adapter's state at the beginning of iavf_remove() and skips the rest of the function if the adapter is already in remove state (shutdown is in progress). Reproducer: 1. Create VF on PF driven by ice or i40e driver 2. Ensure that the VF is bound to iavf driver 3. Reboot [52625.981294] sysrq: SysRq : Show Blocked State [52625.988377] task:reboot state:D stack: 0 pid:17359 ppid: 1 f2 [52625.996732] Call Trace: [52625.999187] __schedule+0x2d1/0x830 [52626.007400] schedule+0x35/0xa0 [52626.010545] schedule_hrtimeout_range_clock+0x83/0x100 [52626.020046] usleep_range+0x5b/0x80 [52626.023540] iavf_remove+0x63/0x5b0 [iavf] [52626.027645] pci_device_remove+0x3b/0xc0 [52626.031572] device_release_driver_internal+0x103/0x1f0 [52626.036805] pci_stop_bus_device+0x72/0xa0 [52626.040904] pci_stop_and_remove_bus_device+0xe/0x20 [52626.045870] pci_iov_remove_virtfn+0xba/0x120 [52626.050232] sriov_disable+0x2f/0xe0 [52626.053813] ice_free_vfs+0x7c/0x340 [ice] [52626.057946] ice_remove+0x220/0x240 [ice] [52626.061967] ice_shutdown+0x16/0x50 [ice] [52626.065987] pci_device_shutdown+0x34/0x60 [52626.070086] device_shutdown+0x165/0x1c5 [52626.074011] kernel_restart+0xe/0x30 [52626.077593] __do_sys_reboot+0x1d2/0x210 [52626.093815] do_syscall_64+0x5b/0x1a0 [52626.097483] entry_SYSCALL_64_after_hwframe+0x65/0xca
| 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 |
iavf: Fix hang during reboot/shutdown