| Message ID | 20170620214024.GA121654@beast (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Quoting Kees Cook (keescook@chromium.org): > Checking for capabilities should be the last operation when performing > access control tests so that PF_SUPERPRIV is set only when it was required > for success (implying that the capability was needed for the operation). > > Reported-by: Solar Designer <solar@openwall.com> > Cc: Serge E. Hallyn <serge@hallyn.com> Makes sense, thanks. Acked-by: Serge Hallyn <serge@hallyn.com> > Cc: Andy Lutomirski <luto@kernel.org> > Signed-off-by: Kees Cook <keescook@chromium.org> > --- > fs/inode.c | 2 +- > fs/namei.c | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/fs/inode.c b/fs/inode.c > index db5914783a71..7092debe90cc 100644 > --- a/fs/inode.c > +++ b/fs/inode.c > @@ -2023,7 +2023,7 @@ bool inode_owner_or_capable(const struct inode *inode) > return true; > > ns = current_user_ns(); > - if (ns_capable(ns, CAP_FOWNER) && kuid_has_mapping(ns, inode->i_uid)) > + if (kuid_has_mapping(ns, inode->i_uid) && ns_capable(ns, CAP_FOWNER)) > return true; > return false; > } > diff --git a/fs/namei.c b/fs/namei.c > index 6571a5f5112e..efe53a5d0737 100644 > --- a/fs/namei.c > +++ b/fs/namei.c > @@ -1008,7 +1008,7 @@ static int may_linkat(struct path *link) > /* Source inode owner (or CAP_FOWNER) can hardlink all they like, > * otherwise, it must be a safe source. > */ > - if (inode_owner_or_capable(inode) || safe_hardlink_source(inode)) > + if (safe_hardlink_source(inode) || inode_owner_or_capable(inode)) > return 0; > > audit_log_link_denied("linkat", link); > -- > 2.7.4 > > > -- > Kees Cook > Pixel Security
On Tue, Jun 20, 2017 at 2:40 PM, Kees Cook <keescook@chromium.org> wrote: > Checking for capabilities should be the last operation when performing > access control tests so that PF_SUPERPRIV is set only when it was required > for success (implying that the capability was needed for the operation). > Reviewed-by: Andy Lutomirski <luto@kernel.org>
On Tue, Jun 20, 2017 at 02:40:24PM -0700, Kees Cook wrote: > Checking for capabilities should be the last operation when performing > access control tests so that PF_SUPERPRIV is set only when it was required > for success (implying that the capability was needed for the operation). Applied
diff --git a/fs/inode.c b/fs/inode.c index db5914783a71..7092debe90cc 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -2023,7 +2023,7 @@ bool inode_owner_or_capable(const struct inode *inode) return true; ns = current_user_ns(); - if (ns_capable(ns, CAP_FOWNER) && kuid_has_mapping(ns, inode->i_uid)) + if (kuid_has_mapping(ns, inode->i_uid) && ns_capable(ns, CAP_FOWNER)) return true; return false; } diff --git a/fs/namei.c b/fs/namei.c index 6571a5f5112e..efe53a5d0737 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1008,7 +1008,7 @@ static int may_linkat(struct path *link) /* Source inode owner (or CAP_FOWNER) can hardlink all they like, * otherwise, it must be a safe source. */ - if (inode_owner_or_capable(inode) || safe_hardlink_source(inode)) + if (safe_hardlink_source(inode) || inode_owner_or_capable(inode)) return 0; audit_log_link_denied("linkat", link);
Checking for capabilities should be the last operation when performing access control tests so that PF_SUPERPRIV is set only when it was required for success (implying that the capability was needed for the operation). Reported-by: Solar Designer <solar@openwall.com> Cc: Serge E. Hallyn <serge@hallyn.com> Cc: Andy Lutomirski <luto@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> --- fs/inode.c | 2 +- fs/namei.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)