On Fri, 2014-05-30 at 21:24 +0300, Dmitry Kasatkin wrote: > On 30 May 2014 20:58, "Mimi Zohar" <zo...@linux.vnet.ibm.com> wrote: > > > > On Fri, 2014-05-30 at 18:58 +0300, Dmitry Kasatkin wrote: > > > On 28 May 2014 18:09, Mimi Zohar <zo...@linux.vnet.ibm.com> wrote: > > > > Dot prefixed keyring names are supposed to be reserved for the > > > > kernel, but add_key() calls key_get_type_from_user(), which > > > > incorrectly verifies the 'type' field, not the 'description' field. > > > > This patch verifies the 'description' field isn't dot prefixed, > > > > when creating a new keyring, and removes the dot prefix test in > > > > key_get_type_from_user(). > > > > > > > > Reported-by: Dmitry Kasatkin <d.kasat...@samsung.com> > > > > Cc: David Howells <dhowe...@redhat.com> > > > > Signed-off-by: Mimi Zohar <zo...@linux.vnet.ibm.com> > > > > --- > > > > security/keys/keyctl.c | 6 ++++-- > > > > 1 file changed, 4 insertions(+), 2 deletions(-) > > > > > > > > diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c > > > > index cd5bd0c..9e9a762 100644 > > > > --- a/security/keys/keyctl.c > > > > +++ b/security/keys/keyctl.c > > > > @@ -37,8 +37,6 @@ static int key_get_type_from_user(char *type, > > > > return ret; > > > > if (ret == 0 || ret >= len) > > > > return -EINVAL; > > > > - if (type[0] == '.') > > > > - return -EPERM; > > > > type[len - 1] = '\0'; > > > > return 0; > > > > } > > > > @@ -87,6 +85,10 @@ SYSCALL_DEFINE5(add_key, const char __user *, > _type, > > > > kfree(description); > > > > description = NULL; > > > > } > > > > + if (description[0] == '.') { > > > > + ret = -EPERM; > > > > + goto error2; > > > > + } > > > > > > 1. 3 lines above "discription = NULL" will cause kernel oops... > > > It happens when using empty description... like: > > > > > > cat x509_ima.der | keyctl padd asymmetric "" keyid > > > > Right, that should be 'else if'. > > > > > 2. It prevents adding trusted keys to ".ima" from user space... > > > This is NOT what we want... right? > > > > It prevents creating a dot prefixed keyring. > > > > May be. But it prevents also adding the key.... > It needs to distinguish key adding and keyring adding then...
Perhaps, but assuming you created a keyring on @u, you would still need to look up the keyid and use it. The same is true here. Instead of using "keyctl search @u keyring _ima", you would use "keyctl describe % keyring:.ima". The first field is the keyring id. Mimi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/