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CVE PROGRAM SOURCE RECORDUnscored

CVE-2021-47593

mptcp: clear 'kern' flag from fallback sockets

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Status
Published
Published
Updated
Assigning organization
Linux

Description

In the Linux kernel, the following vulnerability has been resolved: mptcp: clear 'kern' flag from fallback sockets The mptcp ULP extension relies on sk->sk_sock_kern being set correctly: It prevents setsockopt(fd, IPPROTO_TCP, TCP_ULP, "mptcp", 6); from working for plain tcp sockets (any userspace-exposed socket). But in case of fallback, accept() can return a plain tcp sk. In such case, sk is still tagged as 'kernel' and setsockopt will work. This will crash the kernel, The subflow extension has a NULL ctx->conn mptcp socket: BUG: KASAN: null-ptr-deref in subflow_data_ready+0x181/0x2b0 Call Trace: tcp_data_ready+0xf8/0x370 [..]

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

  • cf7da0d66cc1a2a19fc5930bb746ffbb2d4cd1be to < 451f1eded7f56e93aaf52eb547ba97742d9c0e97affected
  • cf7da0d66cc1a2a19fc5930bb746ffbb2d4cd1be to < c26ac0ea3a91c210cf90452e625dc441adf3e549affected
  • cf7da0d66cc1a2a19fc5930bb746ffbb2d4cd1be to < d6692b3b97bdc165d150f4c1505751a323a80717affected

Linux Linux

Default version status: affected

  • 5.6affected
  • 0 to < 5.6unaffected
  • 5.10.88 to ≤ 5.10.*unaffected
  • 5.15.11 to ≤ 5.15.*unaffected
  • 5.16 to ≤ *unaffected

References