We can break if KEYCTL_READ return value is equal to our buffer size.
From keyctl(2):
On a successful return, the return value is always the total size of
the payload data. To determine whether the buffer was of sufficient
size, check to see that the return value is less than or equal to the
value supplied in arg4.
We'd call loop_write() separately for each char. Let's be nice to
serial console users, and write the full string in one go.
Coverity was complaining that we're not checking the return value
from loop_write(). Rework the code a bit and add voidify.
CID#1402323.
When we read from keyring, a temporary buffer is allocated in order to
determine the size needed for the entire data. However, when zeroing that area,
we use the data size returned by the read instead of the lesser size allocate
for the buffer.
That will cause memory corruption that causes systemd-cryptsetup to crash
either when a single large password is used or when multiple passwords have
already been pushed to the keyring.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
This splits out a bunch of functions from fileio.c that have to do with
temporary files. Simply to make the header files a bit shorter, and to
group things more nicely.
No code changes, just some rearranging of source files.
A race condition happens when calling ask_password_auto() multiple times
to unlock several disks on boot and effectively no password caching is
utilized. This patch fixes it by polling the cache when waiting for
the password.