Hi Nikolaus, all,
> Hi Nikolaus,
> On Wed, 2022-10-12 at 17:09 +0200, Nikolaus Voss wrote:
> > Commit cd3bc044af48 ("KEYS: encrypted: Instantiate key with user-provided
> > decrypted data") added key instantiation with user provided decrypted data.
> > The user data is hex-ascii-encoded but was just memcpy'ed to the binary buffer.
> > Fix this to use hex2bin instead.
> > Keys created from user provided decrypted data saved with "keyctl pipe"
> > are still valid, however if the key is recreated from decrypted data the
> > old key must be converted to the correct format. This can be done with a
> > small shell script, e.g.:
> > BROKENKEY=abcdefABCDEF1234567890aaaaaaaaaa
> > NEWKEY=$(echo -ne $BROKENKEY | xxd -p -c64)
> > keyctl add user masterkey "$(cat masterkey.bin)" @u
> > keyctl add encrypted testkey "new user:masterkey 32 $NEWKEY" @u
> > It is encouraged to switch to a new key because the effective key size
> > of the old keys is only half of the specified size.
> Thank you for updating the patch description.
> > The corresponding test for the Linux Test Project ltp has been fixed
> > with this patch:
> > https://lists.linux.it/pipermail/ltp/2022-October/031060.html
FYI, we use lore, thus:
Link: https://lore.kernel.org/ltp/20221006081709.92303897@xxxxxxxxxxxxxxxxxxx/
> Perhaps make this a "Link:" line and move it before your "Signed-off-
> by".
> > Changes
> > =======
> As per Documentation/process/submitting-patches.rst, the changelog
> belongs after the "---" separator.
> > v2: - clarify commit message, add example to recover old/broken keys
> > - improve example in Documentation/security/keys/trusted-encrypted.rst
> > - add link to ltp patch
> > Fixes: cd3bc044af48 ("KEYS: encrypted: Instantiate key with user-provided decrypted data")
> > Cc: stable <stable@xxxxxxxxxx>
> > Signed-off-by: Nikolaus Voss <nikolaus.voss@xxxxxxxxxxxxxxx>
> > ---
> > Documentation/security/keys/trusted-encrypted.rst | 3 ++-
> > security/keys/encrypted-keys/encrypted.c | 6 +++---
> > 2 files changed, 5 insertions(+), 4 deletions(-)
> > diff --git a/Documentation/security/keys/trusted-encrypted.rst b/Documentation/security/keys/trusted-encrypted.rst
> > index 0bfb4c339748..e81e47db0b4c 100644
> > --- a/Documentation/security/keys/trusted-encrypted.rst
> > +++ b/Documentation/security/keys/trusted-encrypted.rst
> > @@ -350,7 +350,8 @@ Load an encrypted key "evm" from saved blob::
> > Instantiate an encrypted key "evm" using user-provided decrypted data::
> > - $ keyctl add encrypted evm "new default user:kmk 32 `cat evm_decrypted_data.blob`" @u
> > + $ evmkey=abcdefABCDEF1234567890aaaaaaaaaaabcdefABCDEF1234567890aaaaaaaaaa
> > + $ keyctl add encrypted evm "new default user:kmk 32 $evmkey" @u
> > 794890253
> As example code is often re-used, I would avoid including the key data
> on the command line.
