// For flags

CVE-2024-35968

pds_core: Fix pdsc_check_pci_health function to use work thread

Severity Score

"-"
*CVSS v-

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*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

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Track
*SSVC
Descriptions

In the Linux kernel, the following vulnerability has been resolved:

pds_core: Fix pdsc_check_pci_health function to use work thread

When the driver notices fw_status == 0xff it tries to perform a PCI
reset on itself via pci_reset_function() in the context of the driver's
health thread. However, pdsc_reset_prepare calls
pdsc_stop_health_thread(), which attempts to stop/flush the health
thread. This results in a deadlock because the stop/flush will never
complete since the driver called pci_reset_function() from the health
thread context. Fix by changing the pdsc_check_pci_health_function()
to queue a newly introduced pdsc_pci_reset_thread() on the pdsc's
work queue.

Unloading the driver in the fw_down/dead state uncovered another issue,
which can be seen in the following trace:

WARNING: CPU: 51 PID: 6914 at kernel/workqueue.c:1450 __queue_work+0x358/0x440
[...]
RIP: 0010:__queue_work+0x358/0x440
[...]
Call Trace:
<TASK>
? __warn+0x85/0x140
? __queue_work+0x358/0x440
? report_bug+0xfc/0x1e0
? handle_bug+0x3f/0x70
? exc_invalid_op+0x17/0x70
? asm_exc_invalid_op+0x1a/0x20
? __queue_work+0x358/0x440
queue_work_on+0x28/0x30
pdsc_devcmd_locked+0x96/0xe0 [pds_core]
pdsc_devcmd_reset+0x71/0xb0 [pds_core]
pdsc_teardown+0x51/0xe0 [pds_core]
pdsc_remove+0x106/0x200 [pds_core]
pci_device_remove+0x37/0xc0
device_release_driver_internal+0xae/0x140
driver_detach+0x48/0x90
bus_remove_driver+0x6d/0xf0
pci_unregister_driver+0x2e/0xa0
pdsc_cleanup_module+0x10/0x780 [pds_core]
__x64_sys_delete_module+0x142/0x2b0
? syscall_trace_enter.isra.18+0x126/0x1a0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7fbd9d03a14b
[...]

Fix this by preventing the devcmd reset if the FW is not running.

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: pds_core: corrige la función pdsc_check_pci_health para usar el subproceso de trabajo. Cuando el controlador nota fw_status == 0xff, intenta realizar un restablecimiento de PCI sobre sí mismo a través de pci_reset_function() en el contexto del subproceso de estado del controlador. . Sin embargo, pdsc_reset_prepare llama a pdsc_stop_health_thread(), que intenta detener/vaciar el hilo de salud. Esto da como resultado un punto muerto porque la parada/vaciado nunca se completará ya que el controlador llamó a pci_reset_function() desde el contexto del hilo de salud. Para solucionarlo, cambie pdsc_check_pci_health_function() para poner en cola un pdsc_pci_reset_thread() recién introducido en la cola de trabajo del pdsc. La descarga del controlador en el estado fw_down/dead descubrió otro problema, que se puede ver en el siguiente seguimiento: ADVERTENCIA: CPU: 51 PID: 6914 en kernel/workqueue.c:1450 __queue_work+0x358/0x440 [...] RIP: 0010:__queue_work+0x358/0x440 [...] Seguimiento de llamadas: ? __warn+0x85/0x140 ? __queue_work+0x358/0x440? report_bug+0xfc/0x1e0? handle_bug+0x3f/0x70? exc_invalid_op+0x17/0x70? asm_exc_invalid_op+0x1a/0x20? __queue_work+0x358/0x440 queue_work_on+0x28/0x30 pdsc_devcmd_locked+0x96/0xe0 [pds_core] pdsc_devcmd_reset+0x71/0xb0 [pds_core] pdsc_teardown+0x51/0xe0 [pds_core] pdsc_remove+0x106/0x200 [pds_core] pci_device_remove+0x37/0xc0 device_release_driver_internal+0xae /0x140 driver_detach+0x48/0x90 bus_remove_driver+0x6d/0xf0 pci_unregister_driver+0x2e/0xa0 pdsc_cleanup_module+0x10/0x780 [pds_core] __x64_sys_delete_module+0x142/0x2b0 ? syscall_trace_enter.isra.18+0x126/0x1a0 do_syscall_64+0x3b/0x90 Entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7fbd9d03a14b [...] Solucione este problema evitando que devcmd se reinicie si el FW no se está ejecutando.

*Credits: N/A
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* Common Vulnerability Scoring System
SSVC
  • Decision:Track
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No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-05-17 CVE Reserved
  • 2024-05-20 CVE Published
  • 2024-05-21 EPSS Updated
  • 2024-08-02 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.8 < 6.8.7
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.8 < 6.8.7"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.8 < 6.9
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.8 < 6.9"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
6.6.16
Search vendor "Linux" for product "Linux Kernel" and version "6.6.16"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
6.7.4
Search vendor "Linux" for product "Linux Kernel" and version "6.7.4"
en
Affected