d98ee2a19c
The custom ring-buffer implementation was merged without any locking or explicit memory barriers, but a spinlock was later added by commit9d33efd9a7("USB: ldusb bugfix"). The lock did not cover the update of the tail index once the entry had been processed, something which could lead to memory corruption on weakly ordered architectures or due to compiler optimisations. Specifically, a completion handler running on another CPU might observe the incremented tail index and update the entry before ld_usb_read() is done with it. Fixes:2824bd250f("[PATCH] USB: add ldusb driver") Fixes:9d33efd9a7("USB: ldusb bugfix") Cc: stable <stable@vger.kernel.org> # 2.6.13 Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20191022143203.5260-2-johan@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.