Riskcovery

CVE-2021-47591

mptcp: remove tcp ulp setsockopt support

State
Published
Severity
Not scored
Published
Jun 19, 2024
Updated
May 11, 2026
Reserved
May 24, 2024

Read the record on cve.org

Description

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

mptcp: remove tcp ulp setsockopt support

TCP_ULP setsockopt cannot be used for mptcp because its already used internally to plumb subflow (tcp) sockets to the mptcp layer.

syzbot managed to trigger a crash for mptcp connections that are in fallback mode:

KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027] CPU: 1 PID: 1083 Comm: syz-executor.3 Not tainted 5.16.0-rc2-syzkaller #0 RIP: 0010:tls_build_proto net/tls/tls_main.c:776 [inline] [..] __tcp_set_ulp net/ipv4/tcp_ulp.c:139 [inline] tcp_set_ulp+0x428/0x4c0 net/ipv4/tcp_ulp.c:160 do_tcp_setsockopt+0x455/0x37c0 net/ipv4/tcp.c:3391 mptcp_setsockopt+0x1b47/0x2400 net/mptcp/sockopt.c:638

Remove support for TCP_ULP setsockopt.

Scores

The record has no CVSS score.

Weaknesses

The record names no weakness.

Affected Products

ProductVersions
LinuxLinux
  • d9e4c129181004ec94b315b0c9db5eeb09da75e6 to before 3de0c86d42f841d1d64f316cd949e65c566f0734Affected
  • d9e4c129181004ec94b315b0c9db5eeb09da75e6 to before 404cd9a22150f24acf23a8df2ad0c094ba379f57Affected
LinuxLinux
  • 5.13Affected
  • before 5.13Not affected
  • 5.15.11 through 5.15.*Not affected
  • 5.16 and laterNot affected

References

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