// For flags

CVE-2023-52739

Fix page corruption caused by racy check in __free_pages

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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:

Fix page corruption caused by racy check in __free_pages

When we upgraded our kernel, we started seeing some page corruption like
the following consistently:

BUG: Bad page state in process ganesha.nfsd pfn:1304ca
page:0000000022261c55 refcount:0 mapcount:-128 mapping:0000000000000000 index:0x0 pfn:0x1304ca
flags: 0x17ffffc0000000()
raw: 0017ffffc0000000 ffff8a513ffd4c98 ffffeee24b35ec08 0000000000000000
raw: 0000000000000000 0000000000000001 00000000ffffff7f 0000000000000000
page dumped because: nonzero mapcount
CPU: 0 PID: 15567 Comm: ganesha.nfsd Kdump: loaded Tainted: P B O 5.10.158-1.nutanix.20221209.el7.x86_64 #1
Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 04/05/2016
Call Trace:
dump_stack+0x74/0x96
bad_page.cold+0x63/0x94
check_new_page_bad+0x6d/0x80
rmqueue+0x46e/0x970
get_page_from_freelist+0xcb/0x3f0
? _cond_resched+0x19/0x40
__alloc_pages_nodemask+0x164/0x300
alloc_pages_current+0x87/0xf0
skb_page_frag_refill+0x84/0x110
...

Sometimes, it would also show up as corruption in the free list pointer
and cause crashes.

After bisecting the issue, we found the issue started from commit
e320d3012d25 ("mm/page_alloc.c: fix freeing non-compound pages"):

if (put_page_testzero(page))
free_the_page(page, order);
else if (!PageHead(page))
while (order-- > 0)
free_the_page(page + (1 << order), order);

So the problem is the check PageHead is racy because at this point we
already dropped our reference to the page. So even if we came in with
compound page, the page can already be freed and PageHead can return
false and we will end up freeing all the tail pages causing double free.

En el kernel de Linux, se resolvió la siguiente vulnerabilidad: Repare la corrupción de la página causada por el control racy en __free_pages. Cuando actualizamos nuestro kernel, comenzamos a ver algunos daños en la página como los siguientes de manera consistente: ERROR: Estado incorrecto de la página en el proceso ganesha.nfsd pfn: 1304ca página:0000000022261c55 refcount:0 mapcount:-128 mapeo:0000000000000000 índice:0x0 pfn:0x1304ca banderas: 0x17ffffc0000000() raw: 0017ffffc0000000 ffff8a513ffd4c98 24b35ec08 0000000000000000 raw: 00000000000000000 0000000000000001 00000000ffffff7f 00000000000000000 página volcada porque: recuento de mapas distinto de cero CPU: 0 PID: 15567 Comm : ganesha.nfsd Kdump: cargado Contaminado: PBO 5.10.158-1.nutanix.20221209.el7.x86_64 #1 Nombre del hardware: VMware, Inc. Plataforma virtual VMware/Plataforma de referencia de escritorio 440BX, BIOS 6.00 05/04/2016 Seguimiento de llamadas : dump_stack+0x74/0x96 bad_page.cold+0x63/0x94 check_new_page_bad+0x6d/0x80 rmqueue+0x46e/0x970 get_page_from_freelist+0xcb/0x3f0 ? _cond_resched+0x19/0x40 __alloc_pages_nodemask+0x164/0x300 alloc_pages_current+0x87/0xf0 skb_page_frag_refill+0x84/0x110 ... A veces, también aparecería como corrupción en el puntero de la lista libre y provocaría fallos. Después de dividir el problema en dos, encontramos que el problema comenzó desde la confirmación e320d3012d25 ("mm/page_alloc.c: corrige la liberación de páginas no compuestas"): if (put_page_testzero(page)) free_the_page(page, order); else if (!PageHead(página)) while (orden-- &gt; 0) free_the_page(página + (1 &lt;&lt; orden), orden); Entonces, el problema es que la verificación PageHead es picante porque en este punto ya eliminamos nuestra referencia a la página. Entonces, incluso si ingresamos con una página compuesta, la página ya se puede liberar y PageHead puede devolver falso y terminaremos liberando todas las páginas finales causando un double free.

*Credits: N/A
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* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
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* Organization's Worst-case Scenario
Timeline
  • 2024-05-21 CVE Reserved
  • 2024-05-21 CVE Published
  • 2024-05-22 EPSS Updated
  • 2024-09-11 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"
>= 5.10 < 5.10.168
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.10 < 5.10.168"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.10 < 5.15.94
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.10 < 5.15.94"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.10 < 6.1.12
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.10 < 6.1.12"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.10 < 6.2
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.10 < 6.2"
en
Affected
Linux
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Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
5.9.2
Search vendor "Linux" for product "Linux Kernel" and version "5.9.2"
en
Affected