On Mon, May 2, 2022 at 9:39 AM Christian Göttsche
<cgzones@xxxxxxxxxxxxxx> wrote:
> On Wed, 27 Apr 2022 at 15:19, Paul Moore <paul@xxxxxxxxxxxxxx> wrote:
> > On Mon, Apr 4, 2022 at 4:18 PM Paul Moore <paul@xxxxxxxxxxxxxx> wrote:
> > > On Tue, Mar 8, 2022 at 12:09 PM Christian Göttsche
> > > <cgzones@xxxxxxxxxxxxxx> wrote:
> > > >
> > > > Log the anonymous inode class name in the security hook
> > > > inode_init_security_anon. This name is the key for name based type
> > > > transitions on the anon_inode security class on creation. Example:
> > > >
> > > > type=AVC msg=audit(02/16/22 22:02:50.585:216) : avc: granted \
> > > > { create } for pid=2136 comm=mariadbd anonclass="[io_uring]" \
> > > > scontext=system_u:system_r:mysqld_t:s0 \
> > > > tcontext=system_u:system_r:mysqld_iouring_t:s0 tclass=anon_inode
> > > >
> > > > Add a new LSM audit data type holding the inode and the class name.
> > > >
> > > > Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
> > > >
> > > > ---
> > > > v2:
> > > > - drop dev= and name= output for anonymous inodes, and hence simplify
> > > > the common_audit_data union member.
> > > > - drop WARN_ON() on empty name passed to inode_init_security_anon hook
> > > > ---
> > > > include/linux/lsm_audit.h | 2 ++
> > > > security/lsm_audit.c | 4 ++++
> > > > security/selinux/hooks.c | 4 ++--
> > > > 3 files changed, 8 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/include/linux/lsm_audit.h b/include/linux/lsm_audit.h
> > > > index 17d02eda9538..97a8b21eb033 100644
> > > > --- a/include/linux/lsm_audit.h
> > > > +++ b/include/linux/lsm_audit.h
> > > > @@ -76,6 +76,7 @@ struct common_audit_data {
> > > > #define LSM_AUDIT_DATA_IBENDPORT 14
> > > > #define LSM_AUDIT_DATA_LOCKDOWN 15
> > > > #define LSM_AUDIT_DATA_NOTIFICATION 16
> > > > +#define LSM_AUDIT_DATA_ANONINODE 17
> > > > union {
> > > > struct path path;
> > > > struct dentry *dentry;
> > > > @@ -96,6 +97,7 @@ struct common_audit_data {
> > > > struct lsm_ibpkey_audit *ibpkey;
> > > > struct lsm_ibendport_audit *ibendport;
> > > > int reason;
> > > > + const char *anonclass;
> > > > } u;
> > > > /* this union contains LSM specific data */
> > > > union {
> > > > diff --git a/security/lsm_audit.c b/security/lsm_audit.c
> > > > index 1897cbf6fc69..981f6a4e4590 100644
> > > > --- a/security/lsm_audit.c
> > > > +++ b/security/lsm_audit.c
> > > > @@ -433,6 +433,10 @@ static void dump_common_audit_data(struct audit_buffer *ab,
> > > > audit_log_format(ab, " lockdown_reason=\"%s\"",
> > > > lockdown_reasons[a->u.reason]);
> > > > break;
> > > > + case LSM_AUDIT_DATA_ANONINODE:
> > > > + audit_log_format(ab, " anonclass=");
> > > > + audit_log_untrustedstring(ab, a->u.anonclass);
> > >
> > > My apologies, I didn't notice this in the previous patch ... I don't
> > > think we need to log this as an untrusted string as the string value
> > > is coming from the kernel, not userspace, so we could rewrite the
> > > above as the following:
> > >
> > > audit_log_format(ab, " anonclass=%s", a->u.anonclass);
> > >
> > > ... if you are okay with that, I can make the change when I merge the
> > > patch or you can submit another revision, let me know which you would
> > > prefer.
>
> Feel free to adjust while merging, thanks.
Adjusted and merged, thanks.
--
paul-moore.com
