tcp: fix use-after-free in do_tcp_getsockopt(TCP_CC_INFO)

AffectedLinux, Linux

FixUpdate to 7c312f17917455eedcea29735fa302ebb93cb9b9, 66b831b427301a9c3e485564009d476631413103, 8d5fc9e6dc09174d0da6e59678eb8e01a890cbd3, 86814e5370068ec2bf0caa6e6d55c3e5bfc6c324 or newer

PublishedOct 28, 10:34 · Linux

ScoredNot yet

Exploit code publicNone known · checked 21:18 UTC

ExploitedNone known · CISA KEV checked 22:06 UTC

What we know

No known exploitation. CISA KEV, checked 22:06 UTC.

No public exploit code known. Exploit-DB, Metasploit, Nuclei, checked 21:18 UTC.

No severity score yet.

Description

In the Linux kernel, the following vulnerability has been resolved: tcp: fix use-after-free in do_tcp_getsockopt(TCP_CC_INFO) do_tcp_getsockopt() reads icsk->icsk_ca_ops and dereferences the get_info function pointer without rcu_read_lock(). With BPF struct_ops congestion control, ca_ops can point to dynamically allocated memory that is freed concurrently, resulting in a use-after-free when the kernel dereferences or calls through the stale pointer. BUG: KASAN: slab-use-after-free in do_tcp_getsockopt+0x2037/0x23e0 Read of size 8 at addr ffff888013701258 by task exploit/149 do_tcp_getsockopt+0x2037/0x23e0 (net/ipv4/tcp.c:4564) tcp_getsockopt+0x91/0xf0 __sys_getsockopt+0xf7/0x170 Fix this by wrapping the ca_ops load and get_info call within rcu_read_lock()/rcu_read_unlock(), and using READ_ONCE() to load the icsk_ca_ops pointer.

From Linux

Affected and fixed versions

ProductAffectedFixed inLinux0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2 – before 7c312f17917455eedcea29735fa302ebb93cb9b97c312f17917455eedcea29735fa302ebb93cb9b9Linux0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2 – before 66b831b427301a9c3e485564009d47663141310366b831b427301a9c3e485564009d476631413103Linux0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2 – before a8b024cbf62b497062c86995737fc303e4cc384e–Linux0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2 – before 8d5fc9e6dc09174d0da6e59678eb8e01a890cbd38d5fc9e6dc09174d0da6e59678eb8e01a890cbd3Linux0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2 – before e057d201640eebb8ed47ec924872c41570a3bd28–Linux0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2 – before 86814e5370068ec2bf0caa6e6d55c3e5bfc6c32486814e5370068ec2bf0caa6e6d55c3e5bfc6c324Linux0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2 – before 39aa489e85752f9de214edb0f85e4d578e57af2939aa489e85752f9de214edb0f85e4d578e57af29Linux0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2 – before 385e474086c2e7e29e2dded690be40dc273e20ee385e474086c2e7e29e2dded690be40dc273e20eeLinux5.6–LinuxNot affected0LinuxNot affected5.10.273LinuxNot affected5.15.224LinuxNot affected6.1.191LinuxNot affected6.6.161LinuxNot affected6.12.115LinuxNot affected6.18.59LinuxNot affected7.2.13LinuxNot affected7.3

Exploit code

Exploit-DBnone knownMetasploitnone knownNucleinone known

References

git.kernel.org/stable/c/7c312f17917455eedcea29735fa302ebb93cb9b9 · git.kernel.org git.kernel.org/stable/c/66b831b427301a9c3e485564009d476631413103 · git.kernel.org git.kernel.org/stable/c/a8b024cbf62b497062c86995737fc303e4cc384e · git.kernel.org git.kernel.org/stable/c/8d5fc9e6dc09174d0da6e59678eb8e01a890cbd3 · git.kernel.org git.kernel.org/stable/c/e057d201640eebb8ed47ec924872c41570a3bd28 · git.kernel.org git.kernel.org/stable/c/86814e5370068ec2bf0caa6e6d55c3e5bfc6c324 · git.kernel.org git.kernel.org/stable/c/39aa489e85752f9de214edb0f85e4d578e57af29 · git.kernel.org git.kernel.org/stable/c/385e474086c2e7e29e2dded690be40dc273e20ee · git.kernel.org

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