BugLink: http://bugs.launchpad.net/bugs/955892
All failures from __d_path where being treated as disconnected paths,
however __d_path can also fail when the generated pathname is too long.
The initial ENAMETOOLONG error was being lost, and ENAMETOOLONG was only
returned if the subsequent dentry_path call resulted in that error. Other
wise if the path was split across a mount point such that the dentry_path
fit within the buffer when the __d_path did not the failure was treated
as a disconnected path.
Signed-off-by: John Johansen <john.johansen@canonical.com>
BugLink: http://bugs.launchpad.net/bugs/978038
also affects apparmor portion of
BugLink: http://bugs.launchpad.net/bugs/987371
The unconfined profile is not stored in the regular profile list, but
change_profile and exec transitions may want access to it when setting
up specialized transitions like switch to the unconfined profile of a
new policy namespace.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Add support for AppArmor to explicitly fail requested domain transitions
if NO_NEW_PRIVS is set and the task is not unconfined.
Transitions from unconfined are still allowed because this always results
in a reduction of privileges.
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Will Drewry <wad@chromium.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
v18: new acked-by, new description
Signed-off-by: James Morris <james.l.morris@oracle.com>
With this change, calling
prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)
disables privilege granting operations at execve-time. For example, a
process will not be able to execute a setuid binary to change their uid
or gid if this bit is set. The same is true for file capabilities.
Additionally, LSM_UNSAFE_NO_NEW_PRIVS is defined to ensure that
LSMs respect the requested behavior.
To determine if the NO_NEW_PRIVS bit is set, a task may call
prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
It returns 1 if set and 0 if it is not set. If any of the arguments are
non-zero, it will return -1 and set errno to -EINVAL.
(PR_SET_NO_NEW_PRIVS behaves similarly.)
This functionality is desired for the proposed seccomp filter patch
series. By using PR_SET_NO_NEW_PRIVS, it allows a task to modify the
system call behavior for itself and its child tasks without being
able to impact the behavior of a more privileged task.
Another potential use is making certain privileged operations
unprivileged. For example, chroot may be considered "safe" if it cannot
affect privileged tasks.
Note, this patch causes execve to fail when PR_SET_NO_NEW_PRIVS is
set and AppArmor is in use. It is fixed in a subsequent patch.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Will Drewry <wad@chromium.org>
Acked-by: Eric Paris <eparis@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
v18: updated change desc
v17: using new define values as per 3.4
Signed-off-by: James Morris <james.l.morris@oracle.com>
It isn't needed. If you don't set the type of the data associated with
that type it is a pretty obvious programming bug. So why waste the cycles?
Signed-off-by: Eric Paris <eparis@redhat.com>
apparmor is the only LSM that uses the common_audit_data tsk field.
Instead of making all LSMs pay for the stack space move the aa usage into
the apparmor_audit_data.
Signed-off-by: Eric Paris <eparis@redhat.com>
It just bloats the audit data structure for no good reason, since the
only time those fields are filled are just before calling the
common_lsm_audit() function, which is also the only user of those
fields.
So just make them be the arguments to common_lsm_audit(), rather than
bloating that structure that is passed around everywhere, and is
initialized in hot paths.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus found that the gigantic size of the common audit data caused a big
perf hit on something as simple as running stat() in a loop. This patch
requires LSMs to declare the LSM specific portion separately rather than
doing it in a union. Thus each LSM can be responsible for shrinking their
portion and don't have to pay a penalty just because other LSMs have a
bigger space requirement.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix failure in aa_change_onexec api when the request is made from a confined
task. This failure was caused by two problems
The AA_MAY_ONEXEC perm was not being mapped correctly for this case.
The executable name was being checked as second time instead of using the
requested onexec profile name, which may not be the same as the exec
profile name. This mistake can not be exploited to grant extra permission
because of the above flaw where the ONEXEC permission was not being mapped
so it will not be granted.
BugLink: http://bugs.launchpad.net/bugs/963756
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Add the base support for the new policy extensions. This does not bring
any additional functionality, or change current semantics.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
Move the path name lookup failure messages into the main path name lookup
routine, as the information is useful in more than just aa_path_perm.
Also rename aa_get_name to aa_path_name as it is not getting a reference
counted object with a corresponding put fn.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
Update aa_dfa_match so that it doesn't result in an input string being
walked twice (once to get its length and another time to match)
Add a single step functions
aa_dfa_next
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
When __d_path and d_absolute_path fail due to the name being outside of
the current namespace no name is reported. Use dentry_path to provide
some hint as to which file was being accessed.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
Post unpacking of policy a verification pass is made on x transition
indexes. When this fails a call to audit_iface is made resulting in an
oops, because audit_iface is expecting a valid buffer position but
since the failure comes from post unpack verification there is none.
Make the position argument optional so that audit_iface can be called
from post unpack verification.
Signed-off-by: John Johansen <john.johansen@canonical.com>
The returning of -ESATLE when a path lookup fails as disconnected is wrong.
Since AppArmor is rejecting the access return -EACCES instead.
This also fixes a bug in complain (learning) mode where disconnected paths
are denied because -ESTALE errors are not ignored causing failures that
can change application behavior.
Signed-off-by: John Johansen <john.johansen@canonical.com>
When a chroot relative pathname lookup fails it is falling through to
do a d_absolute_path lookup. This is incorrect as d_absolute_path should
only be used to lookup names for namespace absolute paths.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
