CVE-2024-35886

ipv6: Fix infinite recursion in fib6_dump_done().

Severity Score

5.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Track

*SSVC

Descriptions

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

ipv6: Fix infinite recursion in fib6_dump_done().

syzkaller reported infinite recursive calls of fib6_dump_done() during
netlink socket destruction. [1]

From the log, syzkaller sent an AF_UNSPEC RTM_GETROUTE message, and then
the response was generated. The following recvmmsg() resumed the dump
for IPv6, but the first call of inet6_dump_fib() failed at kzalloc() due
to the fault injection. [0]

12:01:34 executing program 3:
r0 = socket$nl_route(0x10, 0x3, 0x0)
sendmsg$nl_route(r0, ... snip ...)
recvmmsg(r0, ... snip ...) (fail_nth: 8)

Here, fib6_dump_done() was set to nlk_sk(sk)->cb.done, and the next call
of inet6_dump_fib() set it to nlk_sk(sk)->cb.args[3]. syzkaller stopped
receiving the response halfway through, and finally netlink_sock_destruct()
called nlk_sk(sk)->cb.done().

fib6_dump_done() calls fib6_dump_end() and nlk_sk(sk)->cb.done() if it
is still not NULL. fib6_dump_end() rewrites nlk_sk(sk)->cb.done() by
nlk_sk(sk)->cb.args[3], but it has the same function, not NULL, calling
itself recursively and hitting the stack guard page.

To avoid the issue, let's set the destructor after kzalloc().

[0]:
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 1 PID: 432110 Comm: syz-executor.3 Not tainted 6.8.0-12821-g537c2e91d354-dirty #11
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl (lib/dump_stack.c:117)
should_fail_ex (lib/fault-inject.c:52 lib/fault-inject.c:153)
should_failslab (mm/slub.c:3733)
kmalloc_trace (mm/slub.c:3748 mm/slub.c:3827 mm/slub.c:3992)
inet6_dump_fib (./include/linux/slab.h:628 ./include/linux/slab.h:749 net/ipv6/ip6_fib.c:662)
rtnl_dump_all (net/core/rtnetlink.c:4029)
netlink_dump (net/netlink/af_netlink.c:2269)
netlink_recvmsg (net/netlink/af_netlink.c:1988)
____sys_recvmsg (net/socket.c:1046 net/socket.c:2801)
___sys_recvmsg (net/socket.c:2846)
do_recvmmsg (net/socket.c:2943)
__x64_sys_recvmmsg (net/socket.c:3041 net/socket.c:3034 net/socket.c:3034)

[1]:
BUG: TASK stack guard page was hit at 00000000f2fa9af1 (stack is 00000000b7912430..000000009a436beb)
stack guard page: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 223719 Comm: kworker/1:3 Not tainted 6.8.0-12821-g537c2e91d354-dirty #11
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Workqueue: events netlink_sock_destruct_work
RIP: 0010:fib6_dump_done (net/ipv6/ip6_fib.c:570)
Code: 3c 24 e8 f3 e9 51 fd e9 28 fd ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 41 57 41 56 41 55 41 54 55 48 89 fd <53> 48 8d 5d 60 e8 b6 4d 07 fd 48 89 da 48 b8 00 00 00 00 00 fc ff
RSP: 0018:ffffc9000d980000 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffffff84405990 RCX: ffffffff844059d3
RDX: ffff8881028e0000 RSI: ffffffff84405ac2 RDI: ffff88810c02f358
RBP: ffff88810c02f358 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000224 R12: 0000000000000000
R13: ffff888007c82c78 R14: ffff888007c82c68 R15: ffff888007c82c68
FS: 0000000000000000(0000) GS:ffff88811b100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc9000d97fff8 CR3: 0000000102309002 CR4: 0000000000770ef0
PKRU: 55555554
Call Trace:
<#DF>
</#DF>
<TASK>
fib6_dump_done (net/ipv6/ip6_fib.c:572 (discriminator 1))
fib6_dump_done (net/ipv6/ip6_fib.c:572 (discriminator 1))
...
fib6_dump_done (net/ipv6/ip6_fib.c:572 (discriminator 1))
fib6_dump_done (net/ipv6/ip6_fib.c:572 (discriminator 1))
netlink_sock_destruct (net/netlink/af_netlink.c:401)
__sk_destruct (net/core/sock.c:2177 (discriminator 2))
sk_destruct (net/core/sock.c:2224)
__sk_free (net/core/sock.c:2235)
sk_free (net/core/sock.c:2246)
process_one_work (kernel/workqueue.c:3259)
worker_thread (kernel/workqueue.c:3329 kernel/workqueue.
---truncated---

En el kernel de Linux se ha resuelto la siguiente vulnerabilidad: ipv6: Se corrigió la recursividad infinita en fib6_dump_done(). syzkaller informó infinitas llamadas recursivas de fib6_dump_done() durante la destrucción del socket netlink. [1] Desde el registro, syzkaller envió un mensaje AF_UNSPEC RTM_GETROUTE y luego se generó la respuesta. El siguiente recvmmsg() reanudó el volcado para IPv6, pero la primera llamada de inet6_dump_fib() falló en kzalloc() debido a la inyección de falla. [0] 12:01:34 ejecutando el programa 3: r0 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route(r0, ... recorte ...) recvmmsg(r0, ... recorte ...) (fail_nth: 8) Aquí, fib6_dump_done() se configuró en nlk_sk(sk)->cb.done, y la siguiente llamada de inet6_dump_fib() se configuró en nlk_sk(sk)->cb.args[3]. syzkaller dejó de recibir la respuesta a la mitad y finalmente netlink_sock_destruct() llamó a nlk_sk(sk)->cb.done(). fib6_dump_done() llama a fib6_dump_end() y nlk_sk(sk)->cb.done() si todavía no es NULL. fib6_dump_end() reescribe nlk_sk(sk)->cb.done() por nlk_sk(sk)->cb.args[3], pero tiene la misma función, no NULL, llamándose a sí mismo de forma recursiva y accediendo a la página de protección de pila. Para evitar el problema, configuremos el destructor después de kzalloc(). [0]: FAULT_INJECTION: forzando un fallo. nombre failslab, intervalo 1, probabilidad 0, espacio 0, tiempos 0 CPU: 1 PID: 432110 Comm: syz-executor.3 Not tainted 6.8.0-12821-g537c2e91d354-dirty #11 Nombre del hardware: PC estándar QEMU (i440FX + PIIX , 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 01/04/2014 Seguimiento de llamadas: dump_stack_lvl (lib/dump_stack.c:117) debería_fail_ex (lib/fault-inject.c :52 lib/fault-inject.c:153) must_failslab (mm/slub.c:3733) kmalloc_trace (mm/slub.c:3748 mm/slub.c:3827 mm/slub.c:3992) inet6_dump_fib (./ include/linux/slab.h:628 ./include/linux/slab.h:749 net/ipv6/ip6_fib.c:662) rtnl_dump_all (net/core/rtnetlink.c:4029) netlink_dump (net/netlink/af_netlink. c:2269) netlink_recvmsg (net/netlink/af_netlink.c:1988) ____sys_recvmsg (net/socket.c:1046 net/socket.c:2801) ___sys_recvmsg (net/socket.c:2846) do_recvmmsg (net/socket.c :2943) __x64_sys_recvmmsg (net/socket.c:3041 net/socket.c:3034 net/socket.c:3034) [1]: ERROR: La página de protección de la pila de TAREA fue visitada en 00000000f2fa9af1 (la pila es 00000000b7912430..000000009a436be b) pila página de protección: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 223719 Comm: kworker/1:3 Not tainted 6.8.0-12821-g537c2e91d354-dirty #11 Nombre de hardware: PC estándar QEMU (i440FX + PIIX, 1996) , BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 01/04/2014 Cola de trabajo: eventos netlink_sock_destruct_work RIP: 0010:fib6_dump_done (net/ipv6/ip6_fib.c:570) Código: 3c 24 e8 f3 e9 51 fd e9 28 fd ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 41 57 41 56 41 55 41 54 55 48 89 fd <53> 48 8d 5d 60 e8 b6 4d 07 fd 48 89 da 48 b8 00 00 00 00 00 fc ff RSP: 0018:ffffc9000d980000 EFLAGS: 00010293 RAX: 00000000000000000 RBX: ffffffff84405990 RCX: ffffffff844059d3 RDX: 881028e0000 RSI: ffffffff84405ac2 RDI: ffff88810c02f358 RBP: ffff88810c02f358 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 0R11: 0000000000000224 R12: 0000000000000000 R13: ffff888007c82c78 R14: ffff888007c82c68 R15: ffff888007c82c68 FS: 0000000000000000(0000) ffff88811b100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc9000d97fff8 CR3: 0000000102309002 000000000770ef0 PKRU : 55555554 Seguimiento de llamadas: <#DF> fib6_dump_done (net/ipv6/ip6_fib.c:572 (discriminador 1)) fib6_dump_done (net/ipv6/ip6_fib.c:572 (discriminador 1)). .. fib6_dump_done (net/ipv6/ip6_fib.c:572 (discriminador 1)) fib6_dump_done (net/ipv6/ip6_fib.c:572 (discriminador 1)) netlink_sock_destruct (net/netlink/af_netlink.c:401) __sk_destruct (net/ core/sock.c:2177 (discriminador 2)) sk_destruct (net/core/sock.c:2224) __sk_free (net/core/sock.c:2235) sk_free (net/core/sock.c:2246) Process_one_work ( kernel/workqueue.c:3259)-truncado-

*Credits: N/A

CVSS Scores

Red Hatv3.1 5.5

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

* Common Vulnerability Scoring System

SSVC

Decision:Track

Exploitation

None

Automatable

Tech. Impact

Partial

* Organization's Worst-case Scenario

Timeline

2024-05-17 CVE Reserved
2024-05-19 CVE Published
2024-05-20 EPSS Updated
2024-11-05 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CAPEC

References (13)

URL	Tag	Source
https://git.kernel.org/stable/c/1da177e4c3f41524e886b7f1b8a0c1fc7321cac2	Vuln. Introduced
https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html
https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html

URL	Date	SRC

URL	Date	SRC
https://git.kernel.org/stable/c/9472d07cd095cbd3294ac54c42f304a38fbe9bfe	2024-04-13
https://git.kernel.org/stable/c/9c5258196182c25b55c33167cd72fdd9bbf08985	2024-04-13
https://git.kernel.org/stable/c/fd307f2d91d40fa7bc55df3e2cd1253fabf8a2d6	2024-04-13
https://git.kernel.org/stable/c/40a344b2ddc06c1a2caa7208a43911f39c662778	2024-04-10
https://git.kernel.org/stable/c/167d4b47a9bdcb01541dfa29e9f3cbb8edd3dfd2	2024-04-10
https://git.kernel.org/stable/c/f2dd75e57285f49e34af1a5b6cd8945c08243776	2024-04-10
https://git.kernel.org/stable/c/4a7c465a5dcd657d59d25bf4815e19ac05c13061	2024-04-10
https://git.kernel.org/stable/c/d21d40605bca7bd5fc23ef03d4c1ca1f48bc2cae	2024-04-03

URL	Date	SRC
https://access.redhat.com/security/cve/CVE-2024-35886	2024-11-12
https://bugzilla.redhat.com/show_bug.cgi?id=2281697	2024-11-12

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"				>= 2.6.12 < 4.19.312 Search vendor "Linux" for product "Linux Kernel" and version " >= 2.6.12 < 4.19.312"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 2.6.12 < 5.4.274 Search vendor "Linux" for product "Linux Kernel" and version " >= 2.6.12 < 5.4.274"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 2.6.12 < 5.10.215 Search vendor "Linux" for product "Linux Kernel" and version " >= 2.6.12 < 5.10.215"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 2.6.12 < 5.15.154 Search vendor "Linux" for product "Linux Kernel" and version " >= 2.6.12 < 5.15.154"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 2.6.12 < 6.1.85 Search vendor "Linux" for product "Linux Kernel" and version " >= 2.6.12 < 6.1.85"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 2.6.12 < 6.6.26 Search vendor "Linux" for product "Linux Kernel" and version " >= 2.6.12 < 6.6.26"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 2.6.12 < 6.8.5 Search vendor "Linux" for product "Linux Kernel" and version " >= 2.6.12 < 6.8.5"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 2.6.12 < 6.9 Search vendor "Linux" for product "Linux Kernel" and version " >= 2.6.12 < 6.9"		en		Affected