1e5a4c74b5
[ Upstream commit df85bc140a4d6cbaa78d8e9c35154e1a2f0622c7 ]
In commit 826f328e2b7e ("net: dcb: Validate netlink message in DCB
handler"), Linux started rejecting RTM_GETDCB netlink messages if they
contained a set-like DCB_CMD_ command.
The reason was that privileges were only verified for RTM_SETDCB messages,
but the value that determined the action to be taken is the command, not
the message type. And validation of message type against the DCB command
was the obvious missing piece.
Unfortunately it turns out that mlnx_qos, a somewhat widely deployed tool
for configuration of DCB, accesses the DCB set-like APIs through
RTM_GETDCB.
Therefore do not bounce the discrepancy between message type and command.
Instead, in addition to validating privileges based on the actual message
type, validate them also based on the expected message type. This closes
the loophole of allowing DCB configuration on non-admin accounts, while
maintaining backward compatibility.
Fixes: 2f90b8657ec9 ("ixgbe: this patch adds support for DCB to the kernel and ixgbe driver")
Fixes: 826f328e2b7e ("net: dcb: Validate netlink message in DCB handler")
Signed-off-by: Petr Machata <petrm@nvidia.com>
Link: https://lore.kernel.org/r/a3edcfda0825f2aa2591801c5232f2bbf2d8a554.1610384801.git.me@pmachata.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.