ec7f0ee2c1
Davide Caratti says: ==================== net/sched: forbid 'goto_chain' on fallback actions the following command: # tc actions add action police rate 1mbit burst 1k conform-exceed \ > pass / goto chain 42 generates a NULL pointer dereference when packets exceed the configured rate. Similarly, the following command: # tc actions add action pass random determ goto chain 42 2 makes the kernel crash with NULL dereference when the first packet does not match the 'pass' action. gact and police allow users to specify a fallback control action, that is stored in the action private data. 'goto chain x' never worked for these cases, since a->goto_chain handle was never initialized. There is only one goto_chain handle per TC action, and it is designed to be non-NULL only if tcf_action contains a 'goto chain' command. So, let's forbid 'goto chain' on fallback actions. Patch 1/4 and 2/4 change the .init() functions of police and gact, to let them return an error when users try to set 'goto chain x' in the fallback action. Patch 3/4 and 4/4 add TDC selftest coverage to this new behavior. ==================== Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.