// For flags

CVE-2022-48651

ipvlan: Fix out-of-bound bugs caused by unset skb->mac_header

Severity Score

7.7
*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:

ipvlan: Fix out-of-bound bugs caused by unset skb->mac_header

If an AF_PACKET socket is used to send packets through ipvlan and the
default xmit function of the AF_PACKET socket is changed from
dev_queue_xmit() to packet_direct_xmit() via setsockopt() with the option
name of PACKET_QDISC_BYPASS, the skb->mac_header may not be reset and
remains as the initial value of 65535, this may trigger slab-out-of-bounds
bugs as following:

=================================================================
UG: KASAN: slab-out-of-bounds in ipvlan_xmit_mode_l2+0xdb/0x330 [ipvlan]
PU: 2 PID: 1768 Comm: raw_send Kdump: loaded Not tainted 6.0.0-rc4+ #6
ardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33
all Trace:
print_address_description.constprop.0+0x1d/0x160
print_report.cold+0x4f/0x112
kasan_report+0xa3/0x130
ipvlan_xmit_mode_l2+0xdb/0x330 [ipvlan]
ipvlan_start_xmit+0x29/0xa0 [ipvlan]
__dev_direct_xmit+0x2e2/0x380
packet_direct_xmit+0x22/0x60
packet_snd+0x7c9/0xc40
sock_sendmsg+0x9a/0xa0
__sys_sendto+0x18a/0x230
__x64_sys_sendto+0x74/0x90
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd

The root cause is:
1. packet_snd() only reset skb->mac_header when sock->type is SOCK_RAW
and skb->protocol is not specified as in packet_parse_headers()

2. packet_direct_xmit() doesn't reset skb->mac_header as dev_queue_xmit()

In this case, skb->mac_header is 65535 when ipvlan_xmit_mode_l2() is
called. So when ipvlan_xmit_mode_l2() gets mac header with eth_hdr() which
use "skb->head + skb->mac_header", out-of-bound access occurs.

This patch replaces eth_hdr() with skb_eth_hdr() in ipvlan_xmit_mode_l2()
and reset mac header in multicast to solve this out-of-bound bug.

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ipvlan: corrige errores fuera de los límites causados por skb->mac_header no configurado si se usa un socket AF_PACKET para enviar paquetes a través de ipvlan y se cambia la función xmit predeterminada del socket AF_PACKET desde dev_queue_xmit() a paquete_direct_xmit() a través de setsockopt() con el nombre de opción PACKET_QDISC_BYPASS, es posible que skb->mac_header no se restablezca y permanezca en el valor inicial de 65535, esto puede desencadenar errores de losa fuera de los límites como se muestra a continuación : =================================================== ================ UG: KASAN: losa fuera de los límites en ipvlan_xmit_mode_l2+0xdb/0x330 [ipvlan] PU: 2 PID: 1768 Comm: raw_send Kdump: cargado No contaminado 6.0.0-rc4+ #6 nombre de hardware: PC estándar QEMU (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 todo Seguimiento: print_address_description.constprop.0+0x1d/0x160 print_report.cold+0x4f/0x112 kasan_report+ 0xa3/0x130 ipvlan_xmit_mode_l2+0xdb/0x330 [ipvlan] ipvlan_start_xmit+0x29/0xa0 [ipvlan] __dev_direct_xmit+0x2e2/0x380 paquete_direct_xmit+0x22/0x60 paquete_snd+0x7c9/0xc40 0x9a/0xa0 __sys_sendto+0x18a/0x230 __x64_sys_sendto+0x74/0x90 do_syscall_64 +0x3b/0x90 Entry_SYSCALL_64_after_hwframe+0x63/0xcd La causa principal es: 1. paquete_snd() solo restablece skb->mac_header cuando sock->tipo es SOCK_RAW y skb->protocolo no se especifica como en paquete_parse_headers() 2. paquete_direct_xmit() no restablece skb->mac_header como dev_queue_xmit() En este caso, skb->mac_header es 65535 cuando se llama a ipvlan_xmit_mode_l2(). Entonces, cuando ipvlan_xmit_mode_l2() obtiene el encabezado mac con eth_hdr() que usa "skb->head + skb->mac_header", se produce un acceso fuera de los límites. Este parche reemplaza eth_hdr() con skb_eth_hdr() en ipvlan_xmit_mode_l2() y restablece el encabezado de mac en multidifusión para resolver este error fuera de los límites.

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
High
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-02-25 CVE Reserved
  • 2024-04-28 CVE Published
  • 2024-04-29 EPSS Updated
  • 2024-12-19 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-125: Out-of-bounds Read
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"
>= 3.19 < 4.9.330
Search vendor "Linux" for product "Linux Kernel" and version " >= 3.19 < 4.9.330"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 3.19 < 4.14.295
Search vendor "Linux" for product "Linux Kernel" and version " >= 3.19 < 4.14.295"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 3.19 < 4.19.260
Search vendor "Linux" for product "Linux Kernel" and version " >= 3.19 < 4.19.260"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 3.19 < 5.4.215
Search vendor "Linux" for product "Linux Kernel" and version " >= 3.19 < 5.4.215"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 3.19 < 5.10.146
Search vendor "Linux" for product "Linux Kernel" and version " >= 3.19 < 5.10.146"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 3.19 < 5.15.71
Search vendor "Linux" for product "Linux Kernel" and version " >= 3.19 < 5.15.71"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 3.19 < 5.19.12
Search vendor "Linux" for product "Linux Kernel" and version " >= 3.19 < 5.19.12"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 3.19 < 6.0
Search vendor "Linux" for product "Linux Kernel" and version " >= 3.19 < 6.0"
en
Affected