CVE-2024-27012

netfilter: nf_tables: restore set elements when delete set fails

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:

netfilter: nf_tables: restore set elements when delete set fails

From abort path, nft_mapelem_activate() needs to restore refcounters to
the original state. Currently, it uses the set->ops->walk() to iterate
over these set elements. The existing set iterator skips inactive
elements in the next generation, this does not work from the abort path
to restore the original state since it has to skip active elements
instead (not inactive ones).

This patch moves the check for inactive elements to the set iterator
callback, then it reverses the logic for the .activate case which
needs to skip active elements.

Toggle next generation bit for elements when delete set command is
invoked and call nft_clear() from .activate (abort) path to restore the
next generation bit.

The splat below shows an object in mappings memleak:

[43929.457523] ------------[ cut here ]------------
[43929.457532] WARNING: CPU: 0 PID: 1139 at include/net/netfilter/nf_tables.h:1237 nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables]
[...]
[43929.458014] RIP: 0010:nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables]
[43929.458076] Code: 83 f8 01 77 ab 49 8d 7c 24 08 e8 37 5e d0 de 49 8b 6c 24 08 48 8d 7d 50 e8 e9 5c d0 de 8b 45 50 8d 50 ff 89 55 50 85 c0 75 86 <0f> 0b eb 82 0f 0b eb b3 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90
[43929.458081] RSP: 0018:ffff888140f9f4b0 EFLAGS: 00010246
[43929.458086] RAX: 0000000000000000 RBX: ffff8881434f5288 RCX: dffffc0000000000
[43929.458090] RDX: 00000000ffffffff RSI: ffffffffa26d28a7 RDI: ffff88810ecc9550
[43929.458093] RBP: ffff88810ecc9500 R08: 0000000000000001 R09: ffffed10281f3e8f
[43929.458096] R10: 0000000000000003 R11: ffff0000ffff0000 R12: ffff8881434f52a0
[43929.458100] R13: ffff888140f9f5f4 R14: ffff888151c7a800 R15: 0000000000000002
[43929.458103] FS: 00007f0c687c4740(0000) GS:ffff888390800000(0000) knlGS:0000000000000000
[43929.458107] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[43929.458111] CR2: 00007f58dbe5b008 CR3: 0000000123602005 CR4: 00000000001706f0
[43929.458114] Call Trace:
[43929.458118] <TASK>
[43929.458121] ? __warn+0x9f/0x1a0
[43929.458127] ? nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables]
[43929.458188] ? report_bug+0x1b1/0x1e0
[43929.458196] ? handle_bug+0x3c/0x70
[43929.458200] ? exc_invalid_op+0x17/0x40
[43929.458211] ? nft_setelem_data_deactivate+0xd7/0xf0 [nf_tables]
[43929.458271] ? nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables]
[43929.458332] nft_mapelem_deactivate+0x24/0x30 [nf_tables]
[43929.458392] nft_rhash_walk+0xdd/0x180 [nf_tables]
[43929.458453] ? __pfx_nft_rhash_walk+0x10/0x10 [nf_tables]
[43929.458512] ? rb_insert_color+0x2e/0x280
[43929.458520] nft_map_deactivate+0xdc/0x1e0 [nf_tables]
[43929.458582] ? __pfx_nft_map_deactivate+0x10/0x10 [nf_tables]
[43929.458642] ? __pfx_nft_mapelem_deactivate+0x10/0x10 [nf_tables]
[43929.458701] ? __rcu_read_unlock+0x46/0x70
[43929.458709] nft_delset+0xff/0x110 [nf_tables]
[43929.458769] nft_flush_table+0x16f/0x460 [nf_tables]
[43929.458830] nf_tables_deltable+0x501/0x580 [nf_tables]

En el kernel de Linux, se resolvió la siguiente vulnerabilidad: netfilter: nf_tables: restaurar elementos del conjunto cuando falla la eliminación del conjunto Desde la ruta de cancelación, nft_mapelem_activate() necesita restaurar los contadores de referencia al estado original. Actualmente, utiliza set->ops->walk() para iterar sobre estos elementos del conjunto. El iterador de conjunto existente omite elementos inactivos en la próxima generación; esto no funciona desde la ruta de cancelación para restaurar el estado original ya que tiene que omitir elementos activos (no inactivos). Este parche mueve la verificación de elementos inactivos a la devolución de llamada del iterador establecido, luego invierte la lógica para el caso .activate que necesita omitir elementos activos. Cambie el bit de próxima generación para los elementos cuando se invoque el comando eliminar conjunto y llame a nft_clear() desde la ruta .activate (abortar) para restaurar el bit de próxima generación. El siguiente símbolo muestra un objeto en asignaciones memleak: [43929.457523] ------------[ cortar aquí ]------------ [43929.457532] ADVERTENCIA: CPU: 0 PID : 1139 en include/net/netfilter/nf_tables.h:1237 nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables] [...] [43929.458014] RIP: 0010:nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables] ] Código: 83 f8 01 77 ab 49 8d 7c 24 08 e8 37 5e d0 de 49 8b 6c 24 08 48 8d 7d 50 e8 e9 5c d0 de 8b 45 50 8d 50 ff 89 55 50 85 c0 75 86 <0f> 0b eb 82 0f 0b eb b3 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 [43929.458081] RSP: 0018:ffff888140f9f4b0 EFLAGS: 00010246 [43929.458086] RAX: 000000000000000 0 RBX: ffff8881434f5288 RCX: dffffc0000000000 [43929.458090] RDX: 00000000ffffffff RSI: ffffffffa26d28a7 RDI: ffff88810ecc9550 [43929.458093 ] RBP: ffff88810ecc9500 R08: 0000000000000001 R09: ffffed10281f3e8f [43929.458096] R10: 00000000000000003 R11: ffff0000ffff0000 R12: 4f52a0 [43929.458100] R13: ffff888140f9f5f4 R14: ffff888151c7a800 R15: 0000000000000002 [43929.458103] FS: 00007f0c687c4740(0000) 88390800000(0000) knlGS :0000000000000000 [43929.458107] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [43929.458111] CR2: 00007f58dbe5b008 CR3: 00000001236020 05 CR4: 00000000001706f0 [43929.458114] Seguimiento de llamadas: [43929.458118] [43929.458121] ? __advertir+0x9f/0x1a0 [43929.458127] ? nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables] [43929.458188] ? report_bug+0x1b1/0x1e0 [43929.458196] ? handle_bug+0x3c/0x70 [43929.458200] ? exc_invalid_op+0x17/0x40 [43929.458211] ? nft_setelem_data_deactivate+0xd7/0xf0 [nf_tables] [43929.458271] ? nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables] [43929.458332] nft_mapelem_deactivate+0x24/0x30 [nf_tables] [43929.458392] nft_rhash_walk+0xdd/0x180 [nf_tables] 53] ? __pfx_nft_rhash_walk+0x10/0x10 [nf_tables] [43929.458512] ? rb_insert_color+0x2e/0x280 [43929.458520] nft_map_deactivate+0xdc/0x1e0 [nf_tables] [43929.458582] ? __pfx_nft_map_deactivate+0x10/0x10 [nf_tables] [43929.458642] ? __pfx_nft_mapelem_deactivate+0x10/0x10 [nf_tables] [43929.458701] ? __rcu_read_unlock+0x46/0x70 [43929.458709] nft_delset+0xff/0x110 [nf_tables] [43929.458769] nft_flush_table+0x16f/0x460 [nf_tables] [43929.458830] 501/0x580 [nf_tables]

*Credits: N/A

CVSS Scores

NISTv3.1 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

2024-02-19 CVE Reserved
2024-05-01 CVE Published
2024-05-13 EPSS Updated
2024-08-02 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-401: Missing Release of Memory after Effective Lifetime

CAPEC

References (9)

URL	Tag	Source
https://git.kernel.org/stable/c/628bd3e49cba1c066228e23d71a852c23e26da73	Vuln. Introduced
https://git.kernel.org/stable/c/bc9f791d2593f17e39f87c6e2b3a36549a3705b1	Vuln. Introduced
https://git.kernel.org/stable/c/3c7ec098e3b588434a8b07ea9b5b36f04cef1f50	Vuln. Introduced
https://git.kernel.org/stable/c/a136b7942ad2a50de708f76ea299ccb45ac7a7f9	Vuln. Introduced
https://git.kernel.org/stable/c/25aa2ad37c2162be1c0bc4fe6397f7e4c13f00f8	Vuln. Introduced
https://git.kernel.org/stable/c/d60be2da67d172aecf866302c91ea11533eca4d9	Vuln. Introduced
https://git.kernel.org/stable/c/dc7cdf8cbcbf8b13de1df93f356ec04cdeef5c41	Vuln. Introduced

URL	Date	SRC

URL	Date	SRC
https://git.kernel.org/stable/c/86658fc7414d4b9e25c2699d751034537503d637	2024-04-27
https://git.kernel.org/stable/c/e79b47a8615d42c68aaeb68971593333667382ed	2024-04-17

URL	Date	SRC

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"				>= 6.4 < 6.8.8 Search vendor "Linux" for product "Linux Kernel" and version " >= 6.4 < 6.8.8"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 6.4 < 6.9 Search vendor "Linux" for product "Linux Kernel" and version " >= 6.4 < 6.9"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				4.19.316 Search vendor "Linux" for product "Linux Kernel" and version "4.19.316"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				5.4.262 Search vendor "Linux" for product "Linux Kernel" and version "5.4.262"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				5.10.188 Search vendor "Linux" for product "Linux Kernel" and version "5.10.188"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				5.15.121 Search vendor "Linux" for product "Linux Kernel" and version "5.15.121"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				6.1.36 Search vendor "Linux" for product "Linux Kernel" and version "6.1.36"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				6.3.10 Search vendor "Linux" for product "Linux Kernel" and version "6.3.10"		en		Affected