Subject: CVE-2021-47215: net/mlx5e: kTLS, Fix crash in RX resync flow

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

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

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

net/mlx5e: kTLS, Fix crash in RX resync flow

For the TLS RX resync flow, we maintain a list of TLS contexts
that require some attention, to communicate their resync information
to the HW.
Here we fix list corruptions, by protecting the entries against
movements coming from resync_handle_seq_match(), until their resync
handling in napi is fully completed.

The Linux kernel CVE team has assigned CVE-2021-47215 to this issue.

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

	Issue introduced in 5.13 with commit e9ce991bce5b and fixed in 5.15.5 with commit ebeda7a9528a
	Issue introduced in 5.13 with commit e9ce991bce5b and fixed in 5.16 with commit cc4a9cc03faa

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-2021-47215
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:
	drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_rx.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/ebeda7a9528ae690e6bf12791a868f0cca8391f2
	https://git.kernel.org/stable/c/cc4a9cc03faa6d8db1a6954bb536f2c1e63bdff6