diff options
| author | Vivek Goyal <vgoyal@redhat.com> | 2016-07-13 17:00:14 +0200 |
|---|---|---|
| committer | Miklos Szeredi <mszeredi@redhat.com> | 2016-07-29 12:05:24 +0200 |
| commit | 500cac3ccee65526d5075da3af2674101305bf8c (patch) | |
| tree | bf22531069f9cb4cce94431dc3aa28f4cbe5820d /fs/timerfd.c | |
| parent | ovl: dilute permission checks on lower only if not special file (diff) | |
| download | linux-500cac3ccee65526d5075da3af2674101305bf8c.tar.xz linux-500cac3ccee65526d5075da3af2674101305bf8c.zip | |
ovl: append MAY_READ when diluting write checks
Right now we remove MAY_WRITE/MAY_APPEND bits from mask if realfile is on
lower/. This is done as files on lower will never be written and will be
copied up. But to copy up a file, mounter should have MAY_READ permission
otherwise copy up will fail. So set MAY_READ in mask when MAY_WRITE is
reset.
Dan Walsh noticed this when he did access(lowerfile, W_OK) and it returned
True (context mounts) but when he tried to actually write to file, it
failed as mounter did not have permission on lower file.
[SzM] don't set MAY_READ if only MAY_APPEND is set without MAY_WRITE; this
won't trigger a copy-up.
Reported-by: Dan Walsh <dwalsh@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'fs/timerfd.c')
0 files changed, 0 insertions, 0 deletions