Subject: CVE-2022-48786: vsock: remove vsock from connected table when connect is interrupted by a signal

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

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

vsock: remove vsock from connected table when connect is interrupted by a signal

vsock_connect() expects that the socket could already be in the
TCP_ESTABLISHED state when the connecting task wakes up with a signal
pending. If this happens the socket will be in the connected table, and
it is not removed when the socket state is reset. In this situation it's
common for the process to retry connect(), and if the connection is
successful the socket will be added to the connected table a second
time, corrupting the list.

Prevent this by calling vsock_remove_connected() if a signal is received
while waiting for a connection. This is harmless if the socket is not in
the connected table, and if it is in the table then removing it will
prevent list corruption from a double add.

Note for backporting: this patch requires d5afa82c977e ("vsock: correct
removal of socket from the list"), which is in all current stable trees
except 4.9.y.

The Linux kernel CVE team has assigned CVE-2022-48786 to this issue.

Affected and fixed versions
===========================

	Issue introduced in 3.9 with commit d021c344051a and fixed in 4.9.303 with commit 0bb88f3f7e8d
	Issue introduced in 3.9 with commit d021c344051a and fixed in 4.14.268 with commit e3b3939fd137
	Issue introduced in 3.9 with commit d021c344051a and fixed in 4.19.231 with commit 2910bcb9f675
	Issue introduced in 3.9 with commit d021c344051a and fixed in 5.4.181 with commit 5f326fe2aef4
	Issue introduced in 3.9 with commit d021c344051a and fixed in 5.10.102 with commit 87cd1bbd6677
	Issue introduced in 3.9 with commit d021c344051a and fixed in 5.15.25 with commit 787468ee7a43
	Issue introduced in 3.9 with commit d021c344051a and fixed in 5.16.11 with commit addd62a8cb6f
	Issue introduced in 3.9 with commit d021c344051a and fixed in 5.17 with commit b9208492fcae

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2022-48786
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	net/vmw_vsock/af_vsock.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/0bb88f3f7e8d506f3efe46d694964117e20efbfc
	https://git.kernel.org/stable/c/e3b3939fd137aab6d00d54bee0ee9244b286a608
	https://git.kernel.org/stable/c/2910bcb9f67551a45397735e47b6d456eb8cd549
	https://git.kernel.org/stable/c/5f326fe2aef411a6575628f92bd861463ea91df7
	https://git.kernel.org/stable/c/87cd1bbd6677411e17369cd4b7389ab1e1fdba44
	https://git.kernel.org/stable/c/787468ee7a435777521d33399d012fd591ae2f94
	https://git.kernel.org/stable/c/addd62a8cb6fa90aa322365c62487da61f6baab8
	https://git.kernel.org/stable/c/b9208492fcaecff8f43915529ae34b3bcb03877c