// For flags

CVE-2024-39474

mm/vmalloc: fix vmalloc which may return null if called with __GFP_NOFAIL

Severity Score

5.5
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

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

mm/vmalloc: fix vmalloc which may return null if called with __GFP_NOFAIL

commit a421ef303008 ("mm: allow !GFP_KERNEL allocations for kvmalloc")
includes support for __GFP_NOFAIL, but it presents a conflict with commit
dd544141b9eb ("vmalloc: back off when the current task is OOM-killed"). A
possible scenario is as follows:

process-a
__vmalloc_node_range(GFP_KERNEL | __GFP_NOFAIL)
__vmalloc_area_node()
vm_area_alloc_pages()
--> oom-killer send SIGKILL to process-a
if (fatal_signal_pending(current)) break;
--> return NULL;

To fix this, do not check fatal_signal_pending() in vm_area_alloc_pages()
if __GFP_NOFAIL set.

This issue occurred during OPLUS KASAN TEST. Below is part of the log
-> oom-killer sends signal to process
[65731.222840] [ T1308] oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null),cpuset=/,mems_allowed=0,global_oom,task_memcg=/apps/uid_10198,task=gs.intelligence,pid=32454,uid=10198

[65731.259685] [T32454] Call trace:
[65731.259698] [T32454] dump_backtrace+0xf4/0x118
[65731.259734] [T32454] show_stack+0x18/0x24
[65731.259756] [T32454] dump_stack_lvl+0x60/0x7c
[65731.259781] [T32454] dump_stack+0x18/0x38
[65731.259800] [T32454] mrdump_common_die+0x250/0x39c [mrdump]
[65731.259936] [T32454] ipanic_die+0x20/0x34 [mrdump]
[65731.260019] [T32454] atomic_notifier_call_chain+0xb4/0xfc
[65731.260047] [T32454] notify_die+0x114/0x198
[65731.260073] [T32454] die+0xf4/0x5b4
[65731.260098] [T32454] die_kernel_fault+0x80/0x98
[65731.260124] [T32454] __do_kernel_fault+0x160/0x2a8
[65731.260146] [T32454] do_bad_area+0x68/0x148
[65731.260174] [T32454] do_mem_abort+0x151c/0x1b34
[65731.260204] [T32454] el1_abort+0x3c/0x5c
[65731.260227] [T32454] el1h_64_sync_handler+0x54/0x90
[65731.260248] [T32454] el1h_64_sync+0x68/0x6c

[65731.260269] [T32454] z_erofs_decompress_queue+0x7f0/0x2258
--> be->decompressed_pages = kvcalloc(be->nr_pages, sizeof(struct page *), GFP_KERNEL | __GFP_NOFAIL);
kernel panic by NULL pointer dereference.
erofs assume kvmalloc with __GFP_NOFAIL never return NULL.
[65731.260293] [T32454] z_erofs_runqueue+0xf30/0x104c
[65731.260314] [T32454] z_erofs_readahead+0x4f0/0x968
[65731.260339] [T32454] read_pages+0x170/0xadc
[65731.260364] [T32454] page_cache_ra_unbounded+0x874/0xf30
[65731.260388] [T32454] page_cache_ra_order+0x24c/0x714
[65731.260411] [T32454] filemap_fault+0xbf0/0x1a74
[65731.260437] [T32454] __do_fault+0xd0/0x33c
[65731.260462] [T32454] handle_mm_fault+0xf74/0x3fe0
[65731.260486] [T32454] do_mem_abort+0x54c/0x1b34
[65731.260509] [T32454] el0_da+0x44/0x94
[65731.260531] [T32454] el0t_64_sync_handler+0x98/0xb4
[65731.260553] [T32454] el0t_64_sync+0x198/0x19c

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mm/vmalloc: corrige vmalloc que puede devolver nulo si se llama con __GFP_NOFAIL commit a421ef303008 ("mm: permitir asignaciones !GFP_KERNEL para kvmalloc") incluye soporte para __GFP_NOFAIL, pero presenta un conflicto con el commit dd544141b9eb ("vmalloc: retroceda cuando la tarea actual sea eliminada por OOM"). Un posible escenario es el siguiente: procesar-a __vmalloc_node_range(GFP_KERNEL | __GFP_NOFAIL) __vmalloc_area_node() vm_area_alloc_pages() --> oom-killer envía SIGKILL al proceso-a if (fatal_signal_pending(current)) break; --> devolver NULO; Para solucionar este problema, no marque fatal_signal_pending() en vm_area_alloc_pages() si __GFP_NOFAIL está configurado. Este problema ocurrió durante la PRUEBA DE OPLUS KASAN. A continuación se muestra parte del registro -> oom-killer envía señal para procesar [65731.222840] [T1308] oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null),cpuset=/,mems_allowed=0,global_oom,task_memcg=/apps/ uid_10198,task=gs.intelligence,pid=32454,uid=10198 [65731.259685] [T32454] Rastreo de llamadas: [65731.259698] [T32454] dump_backtrace+0xf4/0x118 [65731.259734] [T32454] pila+0x18/0x24 [65731.259756] [ T32454] dump_stack_lvl+0x60/0x7c [65731.259781] [T32454] dump_stack+0x18/0x38 [65731.259800] [T32454] mrdump_common_die+0x250/0x39c [mrdump] [65731.259936] T32454] ipanic_die+0x20/0x34 [mrdump] [65731.260019] [ T32454] atomic_notifier_call_chain+0xb4/0xfc [65731.260047] [T32454] notify_die+0x114/0x198 [65731.260073] [T32454] die+0xf4/0x5b4 [65731.260098] [T32454] kernel_fault+0x80/0x98 [65731.260124] [T32454] __do_kernel_fault+0x160/ 0x2a8 [65731.260146] [T32454] do_bad_area+0x68/0x148 [65731.260174] [T32454] do_mem_abort+0x151c/0x1b34 [65731.260204] [T32454] x5c [65731.260227] [T32454] el1h_64_sync_handler+0x54/0x90 [65731.260248] [T32454 ] el1h_64_sync+0x68/0x6c [65731.260269] [T32454] z_erofs_decompress_queue+0x7f0/0x2258 --> be->decompressed_pages = kvcalloc(be->nr_pages, sizeof(struct page *), GFP_KERNEL | __GFP_NOFAIL); pánico del kernel por desreferencia del puntero NULL. erofs supone que kvmalloc con __GFP_NOFAIL nunca devuelve NULL. [65731.260293] [T32454] z_erofs_runqueue+0xf30/0x104c [65731.260314] [T32454] z_erofs_readahead+0x4f0/0x968 [65731.260339] [T32454] c [65731.260364] [T32454] page_cache_ra_unbounded+0x874/0xf30 [65731.260388] [T32454] page_cache_ra_order+0x24c/0x714 [65731.260411] [T32454] filemap_fault+0xbf0/0x1a74 [65731.260437] [T32454] __do_fault+0xd0/0x33c [65731.260462] [T32454] mm_fault+0xf74/0x3fe0 [65731.260486] [T32454] do_mem_abort+0x54c/0x1b34 [ 65731.260509] [T32454] el0_da+0x44/0x94 [65731.260531] [T32454] el0t_64_sync_handler+0x98/0xb4 [65731.260553] [T32454] el0t_64_sync+0x198/0x19c

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Local
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-06-25 CVE Reserved
  • 2024-07-05 CVE Published
  • 2024-07-09 EPSS Updated
  • 2024-12-19 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-476: NULL Pointer Dereference
  • CWE-770: Allocation of Resources Without Limits or Throttling
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"
>= 5.17 < 6.1.95
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.17 < 6.1.95"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.17 < 6.6.34
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.17 < 6.6.34"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.17 < 6.9.5
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.17 < 6.9.5"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.17 < 6.10
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.17 < 6.10"
en
Affected