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]" dev="anon_inodefs" ino=6871 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.
Also warn if the security hook gets called with no name set; currently
the only caller fs/anon_inodes.c:anon_inode_make_secure_inode() passes
one.
Signed-off-by: Christian Göttsche <[email protected]>
---
include/linux/lsm_audit.h | 5 +++++
security/lsm_audit.c | 21 +++++++++++++++++++++
security/selinux/hooks.c | 7 +++++--
3 files changed, 31 insertions(+), 2 deletions(-)
diff --git a/include/linux/lsm_audit.h b/include/linux/lsm_audit.h
index 17d02eda9538..8135a88d6d82 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 +97,10 @@ struct common_audit_data {
struct lsm_ibpkey_audit *ibpkey;
struct lsm_ibendport_audit *ibendport;
int reason;
+ struct {
+ struct inode *inode;
+ const char *anonclass;
+ } anoninode_struct;
} u;
/* this union contains LSM specific data */
union {
diff --git a/security/lsm_audit.c b/security/lsm_audit.c
index 1897cbf6fc69..5545fed35539 100644
--- a/security/lsm_audit.c
+++ b/security/lsm_audit.c
@@ -433,6 +433,27 @@ 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: {
+ struct dentry *dentry;
+ struct inode *inode;
+
+ rcu_read_lock();
+ inode = a->u.anoninode_struct.inode;
+ dentry = d_find_alias_rcu(inode);
+ if (dentry) {
+ audit_log_format(ab, " name=");
+ spin_lock(&dentry->d_lock);
+ audit_log_untrustedstring(ab, dentry->d_name.name);
+ spin_unlock(&dentry->d_lock);
+ }
+ audit_log_format(ab, " anonclass=");
+ audit_log_untrustedstring(ab, a->u.anoninode_struct.anonclass);
+ audit_log_format(ab, " dev=");
+ audit_log_untrustedstring(ab, inode->i_sb->s_id);
+ audit_log_format(ab, " ino=%lu", inode->i_ino);
+ rcu_read_unlock();
+ break;
+ }
} /* switch (a->type) */
}
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index dafabb4dcc64..19c831d94d9b 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2932,6 +2932,8 @@ static int selinux_inode_init_security_anon(struct inode *inode,
if (unlikely(!selinux_initialized(&selinux_state)))
return 0;
+ WARN_ON(!name);
+
isec = selinux_inode(inode);
/*
@@ -2965,8 +2967,9 @@ static int selinux_inode_init_security_anon(struct inode *inode,
* allowed to actually create this type of anonymous inode.
*/
- ad.type = LSM_AUDIT_DATA_INODE;
- ad.u.inode = inode;
+ ad.type = LSM_AUDIT_DATA_ANONINODE;
+ ad.u.anoninode_struct.inode = inode;
+ ad.u.anoninode_struct.anonclass = name ? (const char *)name->name : "unknown(null)";
return avc_has_perm(&selinux_state,
tsec->sid,
--
2.35.1
On Thu, Feb 17, 2022 at 9:35 AM Christian Göttsche
<[email protected]> 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]" dev="anon_inodefs" ino=6871 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.
>
> Also warn if the security hook gets called with no name set; currently
> the only caller fs/anon_inodes.c:anon_inode_make_secure_inode() passes
> one.
>
> Signed-off-by: Christian Göttsche <[email protected]>
> ---
> include/linux/lsm_audit.h | 5 +++++
> security/lsm_audit.c | 21 +++++++++++++++++++++
> security/selinux/hooks.c | 7 +++++--
> 3 files changed, 31 insertions(+), 2 deletions(-)
...
> diff --git a/include/linux/lsm_audit.h b/include/linux/lsm_audit.h
> index 17d02eda9538..8135a88d6d82 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 +97,10 @@ struct common_audit_data {
> struct lsm_ibpkey_audit *ibpkey;
> struct lsm_ibendport_audit *ibendport;
> int reason;
> + struct {
> + struct inode *inode;
> + const char *anonclass;
> + } anoninode_struct;
> } u;
> /* this union contains LSM specific data */
> union {
> diff --git a/security/lsm_audit.c b/security/lsm_audit.c
> index 1897cbf6fc69..5545fed35539 100644
> --- a/security/lsm_audit.c
> +++ b/security/lsm_audit.c
> @@ -433,6 +433,27 @@ 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: {
> + struct dentry *dentry;
> + struct inode *inode;
> +
> + rcu_read_lock();
> + inode = a->u.anoninode_struct.inode;
> + dentry = d_find_alias_rcu(inode);
> + if (dentry) {
> + audit_log_format(ab, " name=");
> + spin_lock(&dentry->d_lock);
> + audit_log_untrustedstring(ab, dentry->d_name.name);
> + spin_unlock(&dentry->d_lock);
> + }
I'm not sure we are ever going to get a useful dentry name for
anonymous inodes, I think we can probably drop this. The "anonclass="
field will likely be much more interesting and helpful.
> + audit_log_format(ab, " anonclass=");
> + audit_log_untrustedstring(ab, a->u.anoninode_struct.anonclass);
> + audit_log_format(ab, " dev=");
> + audit_log_untrustedstring(ab, inode->i_sb->s_id);
I'm pretty sure this is always going to end up being "anon_inodefs"
and thus not very useful.
> + audit_log_format(ab, " ino=%lu", inode->i_ino);
Similarly, I'm not sure how useful the inode number is in practice.
I've never tried, but can a user lookup an anonymous inode via the
inode number?
> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index dafabb4dcc64..19c831d94d9b 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -2932,6 +2932,8 @@ static int selinux_inode_init_security_anon(struct inode *inode,
> if (unlikely(!selinux_initialized(&selinux_state)))
> return 0;
>
> + WARN_ON(!name);
> +
> isec = selinux_inode(inode);
>
> /*
> @@ -2965,8 +2967,9 @@ static int selinux_inode_init_security_anon(struct inode *inode,
> * allowed to actually create this type of anonymous inode.
> */
>
> - ad.type = LSM_AUDIT_DATA_INODE;
> - ad.u.inode = inode;
> + ad.type = LSM_AUDIT_DATA_ANONINODE;
> + ad.u.anoninode_struct.inode = inode;
> + ad.u.anoninode_struct.anonclass = name ? (const char *)name->name : "unknown(null)";
This doesn't seem to match well with the newly added WARN_ON()
assertion above. I would suggest dropping the WARN_ON() assertion as
security_transition_sid() can already handle that safely, and leaving
the tertiary statement above; however I think we should probably
change the anonclass string to "?" as that is the common unset field
value used by audit.
--
paul-moore.com
On Fri, 25 Feb 2022 at 01:25, Paul Moore <[email protected]> wrote:
>
> On Thu, Feb 17, 2022 at 9:35 AM Christian Göttsche
> <[email protected]> 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]" dev="anon_inodefs" ino=6871 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.
> >
> > Also warn if the security hook gets called with no name set; currently
> > the only caller fs/anon_inodes.c:anon_inode_make_secure_inode() passes
> > one.
> >
> > Signed-off-by: Christian Göttsche <[email protected]>
> > ---
> > include/linux/lsm_audit.h | 5 +++++
> > security/lsm_audit.c | 21 +++++++++++++++++++++
> > security/selinux/hooks.c | 7 +++++--
> > 3 files changed, 31 insertions(+), 2 deletions(-)
>
> ...
>
> > diff --git a/include/linux/lsm_audit.h b/include/linux/lsm_audit.h
> > index 17d02eda9538..8135a88d6d82 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 +97,10 @@ struct common_audit_data {
> > struct lsm_ibpkey_audit *ibpkey;
> > struct lsm_ibendport_audit *ibendport;
> > int reason;
> > + struct {
> > + struct inode *inode;
> > + const char *anonclass;
> > + } anoninode_struct;
> > } u;
> > /* this union contains LSM specific data */
> > union {
> > diff --git a/security/lsm_audit.c b/security/lsm_audit.c
> > index 1897cbf6fc69..5545fed35539 100644
> > --- a/security/lsm_audit.c
> > +++ b/security/lsm_audit.c
> > @@ -433,6 +433,27 @@ 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: {
> > + struct dentry *dentry;
> > + struct inode *inode;
> > +
> > + rcu_read_lock();
> > + inode = a->u.anoninode_struct.inode;
> > + dentry = d_find_alias_rcu(inode);
> > + if (dentry) {
> > + audit_log_format(ab, " name=");
> > + spin_lock(&dentry->d_lock);
> > + audit_log_untrustedstring(ab, dentry->d_name.name);
> > + spin_unlock(&dentry->d_lock);
> > + }
>
> I'm not sure we are ever going to get a useful dentry name for
> anonymous inodes, I think we can probably drop this. The "anonclass="
> field will likely be much more interesting and helpful.
>
> > + audit_log_format(ab, " anonclass=");
> > + audit_log_untrustedstring(ab, a->u.anoninode_struct.anonclass);
> > + audit_log_format(ab, " dev=");
> > + audit_log_untrustedstring(ab, inode->i_sb->s_id);
>
> I'm pretty sure this is always going to end up being "anon_inodefs"
> and thus not very useful.
>
> > + audit_log_format(ab, " ino=%lu", inode->i_ino);
>
> Similarly, I'm not sure how useful the inode number is in practice.
> I've never tried, but can a user lookup an anonymous inode via the
> inode number?
>
> > diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> > index dafabb4dcc64..19c831d94d9b 100644
> > --- a/security/selinux/hooks.c
> > +++ b/security/selinux/hooks.c
> > @@ -2932,6 +2932,8 @@ static int selinux_inode_init_security_anon(struct inode *inode,
> > if (unlikely(!selinux_initialized(&selinux_state)))
> > return 0;
> >
> > + WARN_ON(!name);
> > +
> > isec = selinux_inode(inode);
> >
> > /*
> > @@ -2965,8 +2967,9 @@ static int selinux_inode_init_security_anon(struct inode *inode,
> > * allowed to actually create this type of anonymous inode.
> > */
> >
> > - ad.type = LSM_AUDIT_DATA_INODE;
> > - ad.u.inode = inode;
> > + ad.type = LSM_AUDIT_DATA_ANONINODE;
> > + ad.u.anoninode_struct.inode = inode;
> > + ad.u.anoninode_struct.anonclass = name ? (const char *)name->name : "unknown(null)";
>
> This doesn't seem to match well with the newly added WARN_ON()
> assertion above. I would suggest dropping the WARN_ON() assertion as
> security_transition_sid() can already handle that safely, and leaving
> the tertiary statement above; however I think we should probably
> change the anonclass string to "?" as that is the common unset field
> value used by audit.
Is the hook inode_init_security_anon expected to be called with an
empty name though?
The condition was just a fallback to not crash the kernel.
(Dropped in v2.)
>
> --
> paul-moore.com
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 <[email protected]>
---
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);
+ break;
} /* switch (a->type) */
}
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index b12e14b2797b..49c0abfd2f6a 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2965,8 +2965,8 @@ static int selinux_inode_init_security_anon(struct inode *inode,
* allowed to actually create this type of anonymous inode.
*/
- ad.type = LSM_AUDIT_DATA_INODE;
- ad.u.inode = inode;
+ ad.type = LSM_AUDIT_DATA_ANONINODE;
+ ad.u.anonclass = name ? (const char *)name->name : "?";
return avc_has_perm(&selinux_state,
tsec->sid,
--
2.35.1
On Tue, Mar 8, 2022 at 12:09 PM Christian Göttsche
<[email protected]> 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 <[email protected]>
>
> ---
> 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.
The rest of the patch looks good, thanks!
> + break;
> } /* switch (a->type) */
> }
>
> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index b12e14b2797b..49c0abfd2f6a 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -2965,8 +2965,8 @@ static int selinux_inode_init_security_anon(struct inode *inode,
> * allowed to actually create this type of anonymous inode.
> */
>
> - ad.type = LSM_AUDIT_DATA_INODE;
> - ad.u.inode = inode;
> + ad.type = LSM_AUDIT_DATA_ANONINODE;
> + ad.u.anonclass = name ? (const char *)name->name : "?";
>
> return avc_has_perm(&selinux_state,
> tsec->sid,
> --
> 2.35.1
--
paul-moore.com
On Mon, Apr 4, 2022 at 4:18 PM Paul Moore <[email protected]> wrote:
> On Tue, Mar 8, 2022 at 12:09 PM Christian Göttsche
> <[email protected]> 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 <[email protected]>
> >
> > ---
> > 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.
>
> The rest of the patch looks good, thanks!
Hi Christian,
I just wanted to follow up on this as we are at -rc4 this week and if
we want this to go during the next merge window this would need to be
merged soon ...
--
paul-moore.com
On Wed, 27 Apr 2022 at 15:19, Paul Moore <[email protected]> wrote:
>
> On Mon, Apr 4, 2022 at 4:18 PM Paul Moore <[email protected]> wrote:
> > On Tue, Mar 8, 2022 at 12:09 PM Christian Göttsche
> > <[email protected]> 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 <[email protected]>
> > >
> > > ---
> > > 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.
> >
> > The rest of the patch looks good, thanks!
>
> Hi Christian,
>
> I just wanted to follow up on this as we are at -rc4 this week and if
> we want this to go during the next merge window this would need to be
> merged soon ...
>
> --
> paul-moore.com
On Mon, May 2, 2022 at 9:39 AM Christian Göttsche
<[email protected]> wrote:
> On Wed, 27 Apr 2022 at 15:19, Paul Moore <[email protected]> wrote:
> > On Mon, Apr 4, 2022 at 4:18 PM Paul Moore <[email protected]> wrote:
> > > On Tue, Mar 8, 2022 at 12:09 PM Christian Göttsche
> > > <[email protected]> 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 <[email protected]>
> > > >
> > > > ---
> > > > 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