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CVE-2023-52986 (GCVE-0-2023-52986)

Vulnerability from cvelistv5 – Published: 2025-03-27 16:43 – Updated: 2026-05-11 19:36
VLAI
Title
bpf, sockmap: Check for any of tcp_bpf_prots when cloning a listener
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: Check for any of tcp_bpf_prots when cloning a listener A listening socket linked to a sockmap has its sk_prot overridden. It points to one of the struct proto variants in tcp_bpf_prots. The variant depends on the socket's family and which sockmap programs are attached. A child socket cloned from a TCP listener initially inherits their sk_prot. But before cloning is finished, we restore the child's proto to the listener's original non-tcp_bpf_prots one. This happens in tcp_create_openreq_child -> tcp_bpf_clone. Today, in tcp_bpf_clone we detect if the child's proto should be restored by checking only for the TCP_BPF_BASE proto variant. This is not correct. The sk_prot of listening socket linked to a sockmap can point to to any variant in tcp_bpf_prots. If the listeners sk_prot happens to be not the TCP_BPF_BASE variant, then the child socket unintentionally is left if the inherited sk_prot by tcp_bpf_clone. This leads to issues like infinite recursion on close [1], because the child state is otherwise not set up for use with tcp_bpf_prot operations. Adjust the check in tcp_bpf_clone to detect all of tcp_bpf_prots variants. Note that it wouldn't be sufficient to check the socket state when overriding the sk_prot in tcp_bpf_update_proto in order to always use the TCP_BPF_BASE variant for listening sockets. Since commit b8b8315e39ff ("bpf, sockmap: Remove unhash handler for BPF sockmap usage") it is possible for a socket to transition to TCP_LISTEN state while already linked to a sockmap, e.g. connect() -> insert into map -> connect(AF_UNSPEC) -> listen(). [1]: https://lore.kernel.org/all/00000000000073b14905ef2e7401@google.com/
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: e80251555f0befd1271e74b080bccf0ff0348bfc , < 9bd6074e1872d22190a8da30e796cbf937d334f0 (git)
Affected: e80251555f0befd1271e74b080bccf0ff0348bfc , < c681d7a4ed3d360de0574f4d6b7305a8de8dc54f (git)
Affected: e80251555f0befd1271e74b080bccf0ff0348bfc , < 12b0ec7c6953e1602957926439e5297095d7d065 (git)
Affected: e80251555f0befd1271e74b080bccf0ff0348bfc , < ddce1e091757d0259107c6c0c7262df201de2b66 (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.7
Unaffected: 0 , < 5.7 (semver)
Unaffected: 5.10.168 , ≤ 5.10.* (semver)
Unaffected: 5.15.93 , ≤ 5.15.* (semver)
Unaffected: 6.1.11 , ≤ 6.1.* (semver)
Unaffected: 6.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf, sockmap: Check for any of tcp_bpf_prots when cloning a listener\n\nA listening socket linked to a sockmap has its sk_prot overridden. It\npoints to one of the struct proto variants in tcp_bpf_prots. The variant\ndepends on the socket\u0027s family and which sockmap programs are attached.\n\nA child socket cloned from a TCP listener initially inherits their sk_prot.\nBut before cloning is finished, we restore the child\u0027s proto to the\nlistener\u0027s original non-tcp_bpf_prots one. This happens in\ntcp_create_openreq_child -\u003e tcp_bpf_clone.\n\nToday, in tcp_bpf_clone we detect if the child\u0027s proto should be restored\nby checking only for the TCP_BPF_BASE proto variant. This is not\ncorrect. The sk_prot of listening socket linked to a sockmap can point to\nto any variant in tcp_bpf_prots.\n\nIf the listeners sk_prot happens to be not the TCP_BPF_BASE variant, then\nthe child socket unintentionally is left if the inherited sk_prot by\ntcp_bpf_clone.\n\nThis leads to issues like infinite recursion on close [1], because the\nchild state is otherwise not set up for use with tcp_bpf_prot operations.\n\nAdjust the check in tcp_bpf_clone to detect all of tcp_bpf_prots variants.\n\nNote that it wouldn\u0027t be sufficient to check the socket state when\noverriding the sk_prot in tcp_bpf_update_proto in order to always use the\nTCP_BPF_BASE variant for listening sockets. Since commit\nb8b8315e39ff (\"bpf, sockmap: Remove unhash handler for BPF sockmap usage\")\nit is possible for a socket to transition to TCP_LISTEN state while already\nlinked to a sockmap, e.g. connect() -\u003e insert into map -\u003e\nconnect(AF_UNSPEC) -\u003e listen().\n\n[1]: https://lore.kernel.org/all/00000000000073b14905ef2e7401@google.com/"
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            "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: bpf, sockmap: Comprueba si hay alg\u00fan tcp_bpf_prots al clonar un oyente Un socket que escucha vinculado a un sockmap tiene su sk_prot anulado. Apunta a una de las variantes de struct proto en tcp_bpf_prots. La variante depende de la familia del socket y de los programas sockmap que est\u00e9n adjuntos. Un socket hijo clonado de un oyente TCP hereda inicialmente su sk_prot. Pero antes de que finalice la clonaci\u00f3n, restauramos el proto del hijo al original del oyente que no es tcp_bpf_prots. Esto sucede en tcp_create_openreq_child -\u0026gt; tcp_bpf_clone. Hoy, en tcp_bpf_clone detectamos si el proto del hijo debe restaurarse comprobando solo la variante del proto TCP_BPF_BASE. Esto no es correcto. El sk_prot del socket de escucha vinculado a un mapa de socks puede apuntar a cualquier variante de tcp_bpf_prots. Si el sk_prot del socket de escucha no es la variante TCP_BPF_BASE, el socket hijo se abandona involuntariamente si el sk_prot heredado por tcp_bpf_clone lo impide. Esto genera problemas como la recursi\u00f3n infinita al cerrar [1], ya que el estado del hijo no est\u00e1 configurado para su uso con operaciones de tcp_bpf_prot. Ajuste la comprobaci\u00f3n en tcp_bpf_clone para detectar todas las variantes de tcp_bpf_prots. Tenga en cuenta que no ser\u00eda suficiente comprobar el estado del socket al sobrescribir el sk_prot en tcp_bpf_update_proto para usar siempre la variante TCP_BPF_BASE para los sockets de escucha. Desde el commit b8b8315e39ff (\"bpf, sockmap: eliminar el controlador unhash para el uso de sockmap BPF\"), es posible que un socket pase al estado TCP_LISTEN mientras ya est\u00e1 vinculado a un sockmap, por ejemplo, connect() -\u0026gt; insert into map -\u0026gt; connect(AF_UNSPEC) -\u0026gt; listen(). [1]: https://lore.kernel.org/all/00000000000073b14905ef2e7401@google.com/"
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      "title": "kernel: bpf, sockmap: Check for any of tcp_bpf_prots when cloning a listener",
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      "product_status:recommended": "124",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2023-52986",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2023-52986.json",
      "version": "21"
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}



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Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.