lkml.org 
[lkml]   [2022]   [Jun]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 5.10 350/452] f2fs: fix fallocate to use file_modified to update permissions consistently
    Date
    From: Chao Yu <chao@kernel.org>

    commit 958ed92922028ec67f504dcdc72bfdfd0f43936a upstream.

    This patch tries to fix permission consistency issue as all other
    mainline filesystems.

    Since the initial introduction of (posix) fallocate back at the turn of
    the century, it has been possible to use this syscall to change the
    user-visible contents of files. This can happen by extending the file
    size during a preallocation, or through any of the newer modes (punch,
    zero, collapse, insert range). Because the call can be used to change
    file contents, we should treat it like we do any other modification to a
    file -- update the mtime, and drop set[ug]id privileges/capabilities.

    The VFS function file_modified() does all this for us if pass it a
    locked inode, so let's make fallocate drop permissions correctly.

    Cc: stable@kernel.org
    Signed-off-by: Chao Yu <chao.yu@oppo.com>
    Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    ---
    fs/f2fs/file.c | 4 ++++
    1 file changed, 4 insertions(+)

    --- a/fs/f2fs/file.c
    +++ b/fs/f2fs/file.c
    @@ -1744,6 +1744,10 @@ static long f2fs_fallocate(struct file *

    inode_lock(inode);

    + ret = file_modified(file);
    + if (ret)
    + goto out;
    +
    if (mode & FALLOC_FL_PUNCH_HOLE) {
    if (offset >= inode->i_size)
    goto out;

    \
     
     \ /
      Last update: 2022-06-07 20:02    [W:2.426 / U:1.800 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site