diff options
| author |   Miklos Szeredi <mszeredi@redhat.com> | 2017-12-11 11:28:10 +0100 |
|---|---|---|
| committer | Miklos Szeredi <mszeredi@redhat.com> | 2017-12-11 11:28:10 +0100 |
| commit | 438c84c2f0c794f75ab55ce65c505b01bfce4480 (patch) | |
| tree | 1473170ca270435dc5165c04d6690b7bcd6718bb /fs/overlayfs/ovl_entry.h | |
| parent | Linux 4.15-rc2 (diff) | |
| download | linux-dev-438c84c2f0c794f75ab55ce65c505b01bfce4480.tar.xz linux-dev-438c84c2f0c794f75ab55ce65c505b01bfce4480.zip | |
ovl: don't follow redirects if redirect_dir=off
Overlayfs is following redirects even when redirects are disabled. If this
is unintentional (probably the majority of cases) then this can be a
problem. E.g. upper layer comes from untrusted USB drive, and attacker
crafts a redirect to enable read access to otherwise unreadable
directories.
If "redirect_dir=off", then turn off following as well as creation of
redirects. If "redirect_dir=follow", then turn on following, but turn off
creation of redirects (which is what "redirect_dir=off" does now).
This is a backward incompatible change, so make it dependent on a config
option.
Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'fs/overlayfs/ovl_entry.h')
| -rw-r--r-- | fs/overlayfs/ovl_entry.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h index 752bab645879..9d0bc03bf6e4 100644 --- a/fs/overlayfs/ovl_entry.h +++ b/fs/overlayfs/ovl_entry.h @@ -14,6 +14,8 @@ struct ovl_config { char *workdir; bool default_permissions; bool redirect_dir; + bool redirect_follow; + const char *redirect_mode; bool index; }; |