This call is required for deferred removal of device.
Morever, if the system reports that udev is running, we should not
try to "fix" problems by creating or removing nodes directly through libdevmapper.
(Non-udev case should still work.)
this patches improves two areas:
1) it checks for keyslot areas overlaping each other
2) it checks if all keyslot areas fit in header area of device
(pre-data-offset area) or if it can fit file (detached header)
it's being loaded from. Those new checks are based on real data
found in header (offsets) rather than based on assumption calculated
from key length
Because there are already 3 targets used, the current detection
based only on dm-crypt is not sufficient.
Add new definition of dm_flags that allows separate target version detect.
Note: we do not want to load targets explicitly; instead, we repeats
detection after operation that could trigger target load.
If dm_flags() call fails, then the target is not yet loaded.
The dm-integrity target is intended to be used for authenticated
encryption through LUKS and dm-crypt.
It can be used in standalone as well; for this use case there
is a simple configuration utility called integritysetup
(similar to veritysetup to dm-verity).
It is possible to trigger a double free with an invalid verity
partition. All it takes is an unknown hash algorithm, which makes it
a bit more likely than a completely broken partition header. But all
it takes is an error return value of VERITY_read_sb() or strdup().
If crypt_load fails before setting cd->type, crypt_free will handle
the union as if it was of type "none", which means it will call free()
for "active_name", a field which is only properly set up when the
type was actually "none".
In all other cases, "active_name" contains the first 4 or 8 bytes of
the actually used header structure. Fortunately it can be only a
pointer or NULL, so an attacker has no direct control of the value.
Nonetheless it can easily trigger a double free.
Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
