CVE-2024-35853
mlxsw: spectrum_acl_tcam: Fix memory leak during rehash
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
0Exploited in Wild
-Decision
Descriptions
In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrum_acl_tcam: Fix memory leak during rehash
The rehash delayed work migrates filters from one region to another.
This is done by iterating over all chunks (all the filters with the same
priority) in the region and in each chunk iterating over all the
filters.
If the migration fails, the code tries to migrate the filters back to
the old region. However, the rollback itself can also fail in which case
another migration will be erroneously performed. Besides the fact that
this ping pong is not a very good idea, it also creates a problem.
Each virtual chunk references two chunks: The currently used one
('vchunk->chunk') and a backup ('vchunk->chunk2'). During migration the
first holds the chunk we want to migrate filters to and the second holds
the chunk we are migrating filters from.
The code currently assumes - but does not verify - that the backup chunk
does not exist (NULL) if the currently used chunk does not reference the
target region. This assumption breaks when we are trying to rollback a
rollback, resulting in the backup chunk being overwritten and leaked
[1].
Fix by not rolling back a failed rollback and add a warning to avoid
future cases.
[1]
WARNING: CPU: 5 PID: 1063 at lib/parman.c:291 parman_destroy+0x17/0x20
Modules linked in:
CPU: 5 PID: 1063 Comm: kworker/5:11 Tainted: G W 6.9.0-rc2-custom-00784-gc6a05c468a0b #14
Hardware name: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 01/06/2019
Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work
RIP: 0010:parman_destroy+0x17/0x20
[...]
Call Trace:
<TASK>
mlxsw_sp_acl_atcam_region_fini+0x19/0x60
mlxsw_sp_acl_tcam_region_destroy+0x49/0xf0
mlxsw_sp_acl_tcam_vregion_rehash_work+0x1f1/0x470
process_one_work+0x151/0x370
worker_thread+0x2cb/0x3e0
kthread+0xd0/0x100
ret_from_fork+0x34/0x50
ret_from_fork_asm+0x1a/0x30
</TASK>
En el kernel de Linux, se resolvió la siguiente vulnerabilidad: mlxsw: spectrum_acl_tcam: corrige la pérdida de memoria durante el rehash El trabajo retrasado del rehash migra los filtros de una región a otra. Esto se hace iterando sobre todos los fragmentos (todos los filtros con la misma prioridad) en la región y en cada fragmento iterando sobre todos los filtros. Si la migración fallo, el código intenta migrar los filtros nuevamente a la región anterior. Sin embargo, la reversión en sí también puede fallor, en cuyo caso se realizará otra migración por error. Además de que este ping pong no es una muy buena idea, también crea un problema. Cada fragmento virtual hace referencia a dos fragmentos: el que se utiliza actualmente ('vchunk->chunk') y una copia de seguridad ('vchunk->chunk2'). Durante la migración, el primero contiene el fragmento al que queremos migrar los filtros y el segundo contiene el fragmento desde el que estamos migrando los filtros. Actualmente, el código supone, pero no verifica, que el fragmento de copia de seguridad no existe (NULL) si el fragmento utilizado actualmente no hace referencia a la región de destino. Esta suposición se rompe cuando intentamos revertir una reversión, lo que provoca que el fragmento de copia de seguridad se sobrescriba y se filtre [1]. Corrija al no revertir una reversión fallida y agregue una advertencia para evitar casos futuros. [1] ADVERTENCIA: CPU: 5 PID: 1063 en lib/parman.c:291 parman_destroy+0x17/0x20 Módulos vinculados en: CPU: 5 PID: 1063 Comm: kworker/5:11 Tainted: GW 6.9.0-rc2- custom-00784-gc6a05c468a0b #14 Nombre del hardware: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 06/01/2019 Cola de trabajo: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work RIP: 0010:parman_destroy+0x17/0x20 [...] : mlxsw_sp_acl_atcam_region_fini +0x19/0x60 mlxsw_sp_acl_tcam_region_destroy+0x49/0xf0 mlxsw_sp_acl_tcam_vregion_rehash_work+0x1f1/0x470 proceso_one_work+0x151/0x370 trabajador_hilo+0x2cb/0x3e0 kthread+0xd0/0x100 k+0x34/0x50 ret_from_fork_asm+0x1a/0x30
CVSS Scores
SSVC
- Decision:Track
Timeline
- 2024-05-17 CVE Reserved
- 2024-05-17 CVE Published
- 2024-05-18 EPSS Updated
- 2024-08-02 CVE Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
- ---------- First Exploit
CWE
- CWE-416: Use After Free
CAPEC
References (11)
| URL | Tag | Source |
|---|---|---|
| https://git.kernel.org/stable/c/843500518509128a935edab96bd8efef7c54669e | Vuln. Introduced | |
| https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html |
|
| URL | Date | SRC |
|---|
| URL | Date | SRC |
|---|---|---|
| https://access.redhat.com/security/cve/CVE-2024-35853 | 2024-07-08 | |
| https://bugzilla.redhat.com/show_bug.cgi?id=2281255 | 2024-07-08 |
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" | >= 5.1 < 5.4.275 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.1 < 5.4.275" | en |
Affected
| ||||||
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.1 < 5.10.216 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.1 < 5.10.216" | en |
Affected
| ||||||
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.1 < 5.15.158 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.1 < 5.15.158" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.1 < 6.1.90 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.1 < 6.1.90" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.1 < 6.6.30 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.1 < 6.6.30" | en |
Affected
| ||||||
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.1 < 6.8.9 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.1 < 6.8.9" | en |
Affected
| ||||||
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 5.1 < 6.9 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.1 < 6.9" | en |
Affected
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