On Wed, May 29, 2019 at 9:31 PM Darrick J. Wong <darrick.wong@xxxxxxxxxx> wrote: > > On Wed, May 29, 2019 at 08:43:11PM +0300, Amir Goldstein wrote: > > Note that by using the helper, the order of calling file_remove_privs() > > after file_update_mtime() in xfs_file_aio_write_checks() has changed. > > > > Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> > > --- > > fs/xfs/xfs_file.c | 15 +-------------- > > 1 file changed, 1 insertion(+), 14 deletions(-) > > > > diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c > > index 76748255f843..916a35cae5e9 100644 > > --- a/fs/xfs/xfs_file.c > > +++ b/fs/xfs/xfs_file.c > > @@ -367,20 +367,7 @@ xfs_file_aio_write_checks( > > * lock above. Eventually we should look into a way to avoid > > * the pointless lock roundtrip. > > */ > > - if (likely(!(file->f_mode & FMODE_NOCMTIME))) { > > ...especially since here we think NOCMTIME is likely /not/ to be set. > > > - error = file_update_time(file); > > - if (error) > > - return error; > > - } > > - > > - /* > > - * If we're writing the file then make sure to clear the setuid and > > - * setgid bits if the process is not being run by root. This keeps > > - * people from modifying setuid and setgid binaries. > > - */ > > - if (!IS_NOSEC(inode)) > > - return file_remove_privs(file); > > Hm, file_modified doesn't have the !IS_NOSEC check guarding > file_remove_privs, are you sure it's ok to remove the suid bits > unconditionally? Even if SB_NOSEC (and therefore S_NOSEC) are set? > file_remove_privs() has its own IS_NOSEC() check. Thanks, Amir.