7fd3329a4d
commit 3e5e479a39ce9ed60cd63f7565cc1d9da77c2a4e upstream. As Youling reported in mailing list: https://www.linuxquestions.org/questions/linux-newbie-8/the-file-system-f2fs-is-broken-4175666043/ https://www.linux.org/threads/the-file-system-f2fs-is-broken.26490/ There is a test case can corrupt f2fs image: - dd if=/dev/zero of=/swapfile bs=1M count=4096 - chmod 600 /swapfile - mkswap /swapfile - swapon --discard /swapfile The root cause is f2fs_swap_activate() intends to return zero value to setup_swap_extents() to enable SWP_FS mode (swap file goes through fs), in this flow, setup_swap_extents() setups swap extent with wrong block address range, result in discard_swap() erasing incorrect address. Because f2fs_swap_activate() has pinned swapfile, its data block address will not change, it's safe to let swap to handle IO through raw device, so we can get rid of SWAP_FS mode and initial swap extents inside f2fs_swap_activate(), by this way, later discard_swap() can trim in right address range. Fixes: 4969c06a0d83 ("f2fs: support swap file w/ DIO") Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@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.