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* [PATCH v4 0/5] Allow initializing the kernfs node's secctx based on its parent
@ 2019-02-05  8:59 Ondrej Mosnacek
  2019-02-05  8:59 ` [PATCH v4 1/5] selinux: try security xattr after genfs for kernfs filesystems Ondrej Mosnacek
                   ` (4 more replies)
  0 siblings, 5 replies; 10+ messages in thread
From: Ondrej Mosnacek @ 2019-02-05  8:59 UTC (permalink / raw)
  To: selinux, Paul Moore
  Cc: Stephen Smalley, linux-security-module, Casey Schaufler,
	Greg Kroah-Hartman, Tejun Heo, linux-fsdevel, cgroups,
	Ondrej Mosnacek

Changes in v4:
- reorder and rename hook arguments
- avoid allocating kernfs_iattrs unless needed

v3: https://lore.kernel.org/selinux/20190130114150.27807-1-omosnace@redhat.com/T/
Changes in v3:
- rename the hook to "kernfs_init_security"
- change the hook interface to simply pass pointers to struct iattr and
  struct simple_xattrs of both the new node and its parent
- add full security xattr support to kernfs (and fixup SELinux behavior
  to handle it properly)

v2: https://lore.kernel.org/selinux/20190109162830.8309-1-omosnace@redhat.com/T/
Changes in v2:
- add docstring for the new hook in union security_list_options
- initialize *ctx to NULL and *ctxlen to 0 in case the hook is not
  implemented

v1: https://lore.kernel.org/selinux/20190109091028.24485-1-omosnace@redhat.com/T/

TL;DR:
This series adds a new security hook that allows to initialize the security
context of kernfs properly, taking into account the parent context (and
possibly other attributes). Kernfs nodes require special handling here, since
they are not bound to specific inodes/superblocks, but instead represent the
backing tree structure that is used to build the VFS tree when the kernfs
tree is mounted.

The kernfs nodes initially do not store any security context and rely on
the LSM to assign some default context to inodes created over them. Kernfs
inodes, however, allow setting an explicit context via the *setxattr(2)
syscalls, in which case the context is stored inside the kernfs node's
internal structure.

SELinux (and possibly other LSMs) initialize the context of newly created
FS objects based on the parent object's context (usually the child inherits
the parent's context, unless the policy dictates otherwise). This is done
by hooking the creation of the new inode corresponding to the newly created
file/directory via security_inode_init_security() (most filesystems always
create a fresh inode when a new FS object is created). However, kernfs nodes
can be created "behind the scenes" while the filesystem is not mounted
anywhere and thus no inodes can exist for them yet.

Therefore, to allow maintaining similar behavior for kernfs nodes, a new
LSM hook is needed, which will allow initializing the kernfs node's
security context based on its own attributes and those of the parent's
node.

The main motivation for this change is that the userspace users of cgroupfs
(which is built on kernfs) expect the usual security context inheritance
to work under SELinux (see [1] and [2]). This functionality is required for
better confinement of containers under SELinux.

Patch 1/5 changes SELinux to fetch security context from extended
attributes on kernfs filesystems, falling back to genfs-defined context
if that fails. Without this patch the 2/5 would be a regression for
SELinux (due to the removal of ...notifysecctx() call.

Patch 2/5 implements full security xattr support in kernfs using
simple_xattrs; patch 3/5 adds the new LSM hook; patch 4/5 implements the
new hook in SELinux; and patch 5/5 modifies kernfs to call the new hook
on new node creation.

Testing:
- passed the reproducer from the commit message of the last patch
- passed SELinux testsuite on Fedora 29 (x86_64) when applied on top of
  current Rawhide kernel (5.0.0-0.rc5.git0.1) [3]
  - including the new proposed selinux-testsuite subtest [4] (adapted
    from the reproducer)

[1] https://github.com/SELinuxProject/selinux-kernel/issues/39
[2] https://bugzilla.redhat.com/show_bug.cgi?id=1553803
[3] https://copr.fedorainfracloud.org/coprs/omos/kernel-testing/build/854148/
[4] https://github.com/SELinuxProject/selinux-testsuite/pull/48

Ondrej Mosnacek (5):
  selinux: try security xattr after genfs for kernfs filesystems
  kernfs: use simple_xattrs for security attributes
  LSM: add new hook for kernfs node initialization
  selinux: implement the kernfs_init_security hook
  kernfs: initialize security of newly created nodes

 fs/kernfs/dir.c                     |  64 +++++++-
 fs/kernfs/inode.c                   | 125 +++++++---------
 fs/kernfs/kernfs-internal.h         |   7 +-
 include/linux/lsm_hooks.h           |  22 +++
 include/linux/security.h            |  14 ++
 include/linux/xattr.h               |  15 ++
 security/security.c                 |  10 ++
 security/selinux/hooks.c            | 221 +++++++++++++++++++---------
 security/selinux/include/security.h |   1 +
 9 files changed, 328 insertions(+), 151 deletions(-)

-- 
2.20.1


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v4 1/5] selinux: try security xattr after genfs for kernfs filesystems
  2019-02-05  8:59 [PATCH v4 0/5] Allow initializing the kernfs node's secctx based on its parent Ondrej Mosnacek
@ 2019-02-05  8:59 ` Ondrej Mosnacek
  2019-02-05  8:59 ` [PATCH v4 2/5] kernfs: use simple_xattrs for security attributes Ondrej Mosnacek
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 10+ messages in thread
From: Ondrej Mosnacek @ 2019-02-05  8:59 UTC (permalink / raw)
  To: selinux, Paul Moore
  Cc: Stephen Smalley, linux-security-module, Casey Schaufler,
	Greg Kroah-Hartman, Tejun Heo, linux-fsdevel, cgroups,
	Ondrej Mosnacek

Since kernfs supports the security xattr handlers, we can simply use
these to determine the inode's context, dropping the need to update it
from kernfs explicitly using a security_inode_notifysecctx() call.

We achieve this by setting a new sbsec flag SE_SBGENFS_XATTR to all
mounts that are known to use kernfs under the hood and then fetching the
xattrs after determining the fallback genfs sid in
inode_doinit_with_dentry() when this flag is set.

This will allow implementing full security xattr support in kernfs and
removing the ...notifysecctx() call in a subsequent patch.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 security/selinux/hooks.c            | 159 +++++++++++++++-------------
 security/selinux/include/security.h |   1 +
 2 files changed, 88 insertions(+), 72 deletions(-)

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 81e012c66d95..758a99d1086e 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -793,11 +793,13 @@ static int selinux_set_mnt_opts(struct super_block *sb,
 
 	if (!strcmp(sb->s_type->name, "debugfs") ||
 	    !strcmp(sb->s_type->name, "tracefs") ||
-	    !strcmp(sb->s_type->name, "sysfs") ||
-	    !strcmp(sb->s_type->name, "pstore") ||
+	    !strcmp(sb->s_type->name, "pstore"))
+		sbsec->flags |= SE_SBGENFS;
+
+	if (!strcmp(sb->s_type->name, "sysfs") ||
 	    !strcmp(sb->s_type->name, "cgroup") ||
 	    !strcmp(sb->s_type->name, "cgroup2"))
-		sbsec->flags |= SE_SBGENFS;
+		sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
 
 	if (!sbsec->behavior) {
 		/*
@@ -1392,6 +1394,71 @@ static int selinux_genfs_get_sid(struct dentry *dentry,
 	return rc;
 }
 
+static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
+				  u32 def_sid, u32 *sid)
+{
+#define INITCONTEXTLEN 255
+	char *context = NULL;
+	unsigned int len = 0;
+	int rc;
+
+	*sid = def_sid;
+
+	if (!(inode->i_opflags & IOP_XATTR))
+		return 0;
+
+	len = INITCONTEXTLEN;
+	context = kmalloc(len + 1, GFP_NOFS);
+	if (!context)
+		return -ENOMEM;
+
+	context[len] = '\0';
+	rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
+	if (rc == -ERANGE) {
+		kfree(context);
+
+		/* Need a larger buffer.  Query for the right size. */
+		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
+		if (rc < 0)
+			return rc;
+
+		len = rc;
+		context = kmalloc(len + 1, GFP_NOFS);
+		if (!context)
+			return -ENOMEM;
+
+		context[len] = '\0';
+		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
+				    context, len);
+	}
+	if (rc < 0) {
+		kfree(context);
+		if (rc != -ENODATA) {
+			pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
+				__func__, -rc, inode->i_sb->s_id, inode->i_ino);
+			return rc;
+		}
+		return 0;
+	}
+
+	rc = security_context_to_sid_default(&selinux_state, context, rc, sid,
+					     def_sid, GFP_NOFS);
+	if (rc) {
+		char *dev = inode->i_sb->s_id;
+		unsigned long ino = inode->i_ino;
+
+		if (rc == -EINVAL) {
+			pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s.  This indicates you may need to relabel the inode or the filesystem in question.\n",
+					      ino, dev, context);
+		} else {
+			pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
+				__func__, context, -rc, dev, ino);
+		}
+	}
+	kfree(context);
+	return 0;
+}
+
 /* The inode's security attributes must be initialized before first use. */
 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
 {
@@ -1401,8 +1468,6 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
 	u16 sclass;
 	struct dentry *dentry;
 #define INITCONTEXTLEN 255
-	char *context = NULL;
-	unsigned len = 0;
 	int rc = 0;
 
 	if (isec->initialized == LABEL_INITIALIZED)
@@ -1470,72 +1535,11 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
 			goto out;
 		}
 
-		len = INITCONTEXTLEN;
-		context = kmalloc(len+1, GFP_NOFS);
-		if (!context) {
-			rc = -ENOMEM;
-			dput(dentry);
-			goto out;
-		}
-		context[len] = '\0';
-		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
-		if (rc == -ERANGE) {
-			kfree(context);
-
-			/* Need a larger buffer.  Query for the right size. */
-			rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
-			if (rc < 0) {
-				dput(dentry);
-				goto out;
-			}
-			len = rc;
-			context = kmalloc(len+1, GFP_NOFS);
-			if (!context) {
-				rc = -ENOMEM;
-				dput(dentry);
-				goto out;
-			}
-			context[len] = '\0';
-			rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
-		}
+		rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
+					    &sid);
 		dput(dentry);
-		if (rc < 0) {
-			if (rc != -ENODATA) {
-				pr_warn("SELinux: %s:  getxattr returned "
-				       "%d for dev=%s ino=%ld\n", __func__,
-				       -rc, inode->i_sb->s_id, inode->i_ino);
-				kfree(context);
-				goto out;
-			}
-			/* Map ENODATA to the default file SID */
-			sid = sbsec->def_sid;
-			rc = 0;
-		} else {
-			rc = security_context_to_sid_default(&selinux_state,
-							     context, rc, &sid,
-							     sbsec->def_sid,
-							     GFP_NOFS);
-			if (rc) {
-				char *dev = inode->i_sb->s_id;
-				unsigned long ino = inode->i_ino;
-
-				if (rc == -EINVAL) {
-					if (printk_ratelimit())
-						pr_notice("SELinux: inode=%lu on dev=%s was found to have an invalid "
-							"context=%s.  This indicates you may need to relabel the inode or the "
-							"filesystem in question.\n", ino, dev, context);
-				} else {
-					pr_warn("SELinux: %s:  context_to_sid(%s) "
-					       "returned %d for dev=%s ino=%ld\n",
-					       __func__, context, -rc, dev, ino);
-				}
-				kfree(context);
-				/* Leave with the unlabeled SID */
-				rc = 0;
-				break;
-			}
-		}
-		kfree(context);
+		if (rc)
+			goto out;
 		break;
 	case SECURITY_FS_USE_TASK:
 		sid = task_sid;
@@ -1586,9 +1590,20 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
 				goto out;
 			rc = selinux_genfs_get_sid(dentry, sclass,
 						   sbsec->flags, &sid);
-			dput(dentry);
-			if (rc)
+			if (rc) {
+				dput(dentry);
 				goto out;
+			}
+
+			if (sbsec->flags & SE_SBGENFS_XATTR) {
+				rc = inode_doinit_use_xattr(inode, dentry,
+							    sid, &sid);
+				if (rc) {
+					dput(dentry);
+					goto out;
+				}
+			}
+			dput(dentry);
 		}
 		break;
 	}
diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
index f68fb25b5702..6e5928f951da 100644
--- a/security/selinux/include/security.h
+++ b/security/selinux/include/security.h
@@ -58,6 +58,7 @@
 #define SE_SBINITIALIZED	0x0100
 #define SE_SBPROC		0x0200
 #define SE_SBGENFS		0x0400
+#define SE_SBGENFS_XATTR	0x0800
 
 #define CONTEXT_STR	"context="
 #define FSCONTEXT_STR	"fscontext="
-- 
2.20.1


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v4 2/5] kernfs: use simple_xattrs for security attributes
  2019-02-05  8:59 [PATCH v4 0/5] Allow initializing the kernfs node's secctx based on its parent Ondrej Mosnacek
  2019-02-05  8:59 ` [PATCH v4 1/5] selinux: try security xattr after genfs for kernfs filesystems Ondrej Mosnacek
@ 2019-02-05  8:59 ` Ondrej Mosnacek
  2019-02-05  8:59 ` [PATCH v4 3/5] LSM: add new hook for kernfs node initialization Ondrej Mosnacek
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 10+ messages in thread
From: Ondrej Mosnacek @ 2019-02-05  8:59 UTC (permalink / raw)
  To: selinux, Paul Moore
  Cc: Stephen Smalley, linux-security-module, Casey Schaufler,
	Greg Kroah-Hartman, Tejun Heo, linux-fsdevel, cgroups,
	Ondrej Mosnacek

Replace the special handling of security xattrs with simple_xattrs, as
is already done for the trusted xattrs. This simplifies the code and
allows LSMs to use more than just a single xattr to do their business.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 fs/kernfs/dir.c             |   7 ++-
 fs/kernfs/inode.c           | 100 +++++++++++++++---------------------
 fs/kernfs/kernfs-internal.h |   5 +-
 3 files changed, 46 insertions(+), 66 deletions(-)

diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index 4ca0b5c18192..ad7e3356bcc5 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -532,11 +532,10 @@ void kernfs_put(struct kernfs_node *kn)
 	kfree_const(kn->name);
 
 	if (kn->iattr) {
-		if (kn->iattr->ia_secdata)
-			security_release_secctx(kn->iattr->ia_secdata,
-						kn->iattr->ia_secdata_len);
-		simple_xattrs_free(&kn->iattr->xattrs);
+		simple_xattrs_free(&kn->iattr->xattrs_trusted);
+		simple_xattrs_free(&kn->iattr->xattrs_security);
 	}
+
 	kfree(kn->iattr);
 	spin_lock(&kernfs_idr_lock);
 	idr_remove(&root->ino_idr, kn->id.ino);
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index 80cebcd94c90..f0e2cb4379c0 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -56,7 +56,8 @@ static struct kernfs_iattrs *kernfs_iattrs(struct kernfs_node *kn)
 	iattrs->ia_mtime = iattrs->ia_atime;
 	iattrs->ia_ctime = iattrs->ia_atime;
 
-	simple_xattrs_init(&kn->iattr->xattrs);
+	simple_xattrs_init(&kn->iattr->xattrs_trusted);
+	simple_xattrs_init(&kn->iattr->xattrs_security);
 out_unlock:
 	ret = kn->iattr;
 	mutex_unlock(&iattr_mutex);
@@ -135,33 +136,31 @@ out:
 	return error;
 }
 
-static int kernfs_node_setsecdata(struct kernfs_iattrs *attrs, void **secdata,
-				  u32 *secdata_len)
-{
-	void *old_secdata;
-	size_t old_secdata_len;
-
-	old_secdata = attrs->ia_secdata;
-	old_secdata_len = attrs->ia_secdata_len;
-
-	attrs->ia_secdata = *secdata;
-	attrs->ia_secdata_len = *secdata_len;
-
-	*secdata = old_secdata;
-	*secdata_len = old_secdata_len;
-	return 0;
-}
-
 ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size)
 {
 	struct kernfs_node *kn = kernfs_dentry_node(dentry);
+	struct inode *inode = d_inode(dentry);
 	struct kernfs_iattrs *attrs;
+	ssize_t ret, length = 0;
 
 	attrs = kernfs_iattrs(kn);
 	if (!attrs)
 		return -ENOMEM;
 
-	return simple_xattr_list(d_inode(dentry), &attrs->xattrs, buf, size);
+	ret = simple_xattr_list(inode, &attrs->xattrs_trusted, buf, size);
+	if (ret < 0)
+		return ret;
+	length += ret;
+
+	buf += ret;
+	size -= ret;
+
+	ret = simple_xattr_list(inode, &attrs->xattrs_security, buf, size);
+	if (ret < 0)
+		return ret;
+	length += ret;
+
+	return length;
 }
 
 static inline void set_default_inode_attr(struct inode *inode, umode_t mode)
@@ -186,15 +185,12 @@ static void kernfs_refresh_inode(struct kernfs_node *kn, struct inode *inode)
 	struct kernfs_iattrs *attrs = kn->iattr;
 
 	inode->i_mode = kn->mode;
-	if (attrs) {
+	if (attrs)
 		/*
 		 * kernfs_node has non-default attributes get them from
 		 * persistent copy in kernfs_node.
 		 */
 		set_inode_attr(inode, &attrs->ia_iattr);
-		security_inode_notifysecctx(inode, attrs->ia_secdata,
-					    attrs->ia_secdata_len);
-	}
 
 	if (kernfs_type(kn) == KERNFS_DIR)
 		set_nlink(inode, kn->dir.subdirs + 2);
@@ -305,19 +301,29 @@ int kernfs_iop_permission(struct inode *inode, int mask)
 	return generic_permission(inode, mask);
 }
 
+static const struct xattr_handler kernfs_trusted_xattr_handler;
+static const struct xattr_handler kernfs_security_xattr_handler;
+
 static int kernfs_xattr_get(const struct xattr_handler *handler,
 			    struct dentry *unused, struct inode *inode,
 			    const char *suffix, void *value, size_t size)
 {
-	const char *name = xattr_full_name(handler, suffix);
 	struct kernfs_node *kn = inode->i_private;
 	struct kernfs_iattrs *attrs;
+	struct simple_xattrs *xattrs;
 
 	attrs = kernfs_iattrs(kn);
 	if (!attrs)
 		return -ENOMEM;
 
-	return simple_xattr_get(&attrs->xattrs, name, value, size);
+	if (handler == &kernfs_trusted_xattr_handler)
+		xattrs = &attrs->xattrs_trusted;
+	else if (handler == &kernfs_security_xattr_handler)
+		xattrs = &attrs->xattrs_security;
+	else
+		return -EINVAL;
+
+	return simple_xattr_get(xattrs, suffix, value, size);
 }
 
 static int kernfs_xattr_set(const struct xattr_handler *handler,
@@ -325,15 +331,22 @@ static int kernfs_xattr_set(const struct xattr_handler *handler,
 			    const char *suffix, const void *value,
 			    size_t size, int flags)
 {
-	const char *name = xattr_full_name(handler, suffix);
 	struct kernfs_node *kn = inode->i_private;
 	struct kernfs_iattrs *attrs;
+	struct simple_xattrs *xattrs;
 
 	attrs = kernfs_iattrs(kn);
 	if (!attrs)
 		return -ENOMEM;
 
-	return simple_xattr_set(&attrs->xattrs, name, value, size, flags);
+	if (handler == &kernfs_trusted_xattr_handler)
+		xattrs = &attrs->xattrs_trusted;
+	else if (handler == &kernfs_security_xattr_handler)
+		xattrs = &attrs->xattrs_security;
+	else
+		return -EINVAL;
+
+	return simple_xattr_set(xattrs, suffix, value, size, flags);
 }
 
 static const struct xattr_handler kernfs_trusted_xattr_handler = {
@@ -342,41 +355,10 @@ static const struct xattr_handler kernfs_trusted_xattr_handler = {
 	.set = kernfs_xattr_set,
 };
 
-static int kernfs_security_xattr_set(const struct xattr_handler *handler,
-				     struct dentry *unused, struct inode *inode,
-				     const char *suffix, const void *value,
-				     size_t size, int flags)
-{
-	struct kernfs_node *kn = inode->i_private;
-	struct kernfs_iattrs *attrs;
-	void *secdata;
-	u32 secdata_len = 0;
-	int error;
-
-	attrs = kernfs_iattrs(kn);
-	if (!attrs)
-		return -ENOMEM;
-
-	error = security_inode_setsecurity(inode, suffix, value, size, flags);
-	if (error)
-		return error;
-	error = security_inode_getsecctx(inode, &secdata, &secdata_len);
-	if (error)
-		return error;
-
-	mutex_lock(&kernfs_mutex);
-	error = kernfs_node_setsecdata(attrs, &secdata, &secdata_len);
-	mutex_unlock(&kernfs_mutex);
-
-	if (secdata)
-		security_release_secctx(secdata, secdata_len);
-	return error;
-}
-
 static const struct xattr_handler kernfs_security_xattr_handler = {
 	.prefix = XATTR_SECURITY_PREFIX,
 	.get = kernfs_xattr_get,
-	.set = kernfs_security_xattr_set,
+	.set = kernfs_xattr_set,
 };
 
 const struct xattr_handler *kernfs_xattr_handlers[] = {
diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h
index 3d83b114bb08..93bf1dcd0306 100644
--- a/fs/kernfs/kernfs-internal.h
+++ b/fs/kernfs/kernfs-internal.h
@@ -20,10 +20,9 @@
 
 struct kernfs_iattrs {
 	struct iattr		ia_iattr;
-	void			*ia_secdata;
-	u32			ia_secdata_len;
 
-	struct simple_xattrs	xattrs;
+	struct simple_xattrs	xattrs_trusted;
+	struct simple_xattrs	xattrs_security;
 };
 
 /* +1 to avoid triggering overflow warning when negating it */
-- 
2.20.1


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v4 3/5] LSM: add new hook for kernfs node initialization
  2019-02-05  8:59 [PATCH v4 0/5] Allow initializing the kernfs node's secctx based on its parent Ondrej Mosnacek
  2019-02-05  8:59 ` [PATCH v4 1/5] selinux: try security xattr after genfs for kernfs filesystems Ondrej Mosnacek
  2019-02-05  8:59 ` [PATCH v4 2/5] kernfs: use simple_xattrs for security attributes Ondrej Mosnacek
@ 2019-02-05  8:59 ` Ondrej Mosnacek
  2019-02-05  9:51   ` kbuild test robot
  2019-02-05 10:25   ` kbuild test robot
  2019-02-05  8:59 ` [PATCH v4 4/5] selinux: implement the kernfs_init_security hook Ondrej Mosnacek
  2019-02-05  8:59 ` [PATCH v4 5/5] kernfs: initialize security of newly created nodes Ondrej Mosnacek
  4 siblings, 2 replies; 10+ messages in thread
From: Ondrej Mosnacek @ 2019-02-05  8:59 UTC (permalink / raw)
  To: selinux, Paul Moore
  Cc: Stephen Smalley, linux-security-module, Casey Schaufler,
	Greg Kroah-Hartman, Tejun Heo, linux-fsdevel, cgroups,
	Ondrej Mosnacek

This patch introduces a new security hook that is intended for
initializing the security data for newly created kernfs nodes, which
provide a way of storing a non-default security context, but need to
operate independently from mounts (and therefore may not have an
associated inode at the moment of creation).

The main motivation is to allow kernfs nodes to inherit the context of
the parent under SELinux, similar to the behavior of
security_inode_init_security(). Other LSMs may implement their own logic
for handling the creation of new nodes.

The interface of the new hook provides the following to the LSM:
 * a qstr containing the name of the new node
 * inode attributes of the parent node (directory)
 * initial inode attributes (struct iattr + simple_xattrs) of the new
   node

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 include/linux/lsm_hooks.h | 22 ++++++++++++++++++++++
 include/linux/security.h  | 14 ++++++++++++++
 security/security.c       | 10 ++++++++++
 3 files changed, 46 insertions(+)

diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 9a0bdf91e646..558bbc0ff125 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -429,6 +429,21 @@
  *	to abort the copy up. Note that the caller is responsible for reading
  *	and writing the xattrs as this hook is merely a filter.
  *
+ * Security hooks for kernfs node operations
+ *
+ * @kernfs_init_security
+ *	Initialize the security context of a newlycreated kernfs node based
+ *	on its own and its parent's attributes. The security context (or other
+ *	LSM metadata) should be stored in @secattr as extended attributes.
+ *	The hook MAY NOT add/modify attributes in @dir_secattr; it should be
+ *	treated as a read-only list of attributes.
+ *
+ *	@qstr contains the last path component of the new node.
+ *	@dir_iattr contains the inode attributes of the parent node.
+ *	@dir_secattr is the list of security xattrs of the parent node.
+ *	@iattr contains the inode attributes of the new node.
+ *	@secattr is the list of security xattrs of the new node.
+ *
  * Security hooks for file operations
  *
  * @file_permission:
@@ -1558,6 +1573,12 @@ union security_list_options {
 	int (*inode_copy_up)(struct dentry *src, struct cred **new);
 	int (*inode_copy_up_xattr)(const char *name);
 
+	int (*kernfs_init_security)(const struct qstr *qstr,
+				    const struct iattr *dir_iattr,
+				    struct simple_xattrs *dir_secattr,
+				    const struct iattr *iattr,
+				    struct simple_xattrs *secattr);
+
 	int (*file_permission)(struct file *file, int mask);
 	int (*file_alloc_security)(struct file *file);
 	void (*file_free_security)(struct file *file);
@@ -1858,6 +1879,7 @@ struct security_hook_heads {
 	struct hlist_head inode_getsecid;
 	struct hlist_head inode_copy_up;
 	struct hlist_head inode_copy_up_xattr;
+	struct hlist_head kernfs_init_security;
 	struct hlist_head file_permission;
 	struct hlist_head file_alloc_security;
 	struct hlist_head file_free_security;
diff --git a/include/linux/security.h b/include/linux/security.h
index dbfb5a66babb..5b2aeb2457ab 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -51,6 +51,7 @@ struct fown_struct;
 struct file_operations;
 struct msg_msg;
 struct xattr;
+struct simple_xattrs;
 struct xfrm_sec_ctx;
 struct mm_struct;
 
@@ -291,6 +292,11 @@ int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer
 void security_inode_getsecid(struct inode *inode, u32 *secid);
 int security_inode_copy_up(struct dentry *src, struct cred **new);
 int security_inode_copy_up_xattr(const char *name);
+int security_kernfs_init_security(const struct qstr *qstr,
+				  const struct iattr *dir_iattr,
+				  struct simple_xattrs *dir_secattr,
+				  const struct iattr *iattr,
+				  struct simple_xattrs *secattr);
 int security_file_permission(struct file *file, int mask);
 int security_file_alloc(struct file *file);
 void security_file_free(struct file *file);
@@ -783,6 +789,14 @@ static inline int security_inode_copy_up(struct dentry *src, struct cred **new)
 	return 0;
 }
 
+static inline int security_kernfs_init_security(
+		const struct qstr *qstr, const struct iattr *dir_iattr,
+		struct simple_xattrs *dir_secattr, const struct iattr *iattr,
+		struct simple_xattrs *secattr);
+{
+	return 0;
+}
+
 static inline int security_inode_copy_up_xattr(const char *name)
 {
 	return -EOPNOTSUPP;
diff --git a/security/security.c b/security/security.c
index f1b8d2587639..836e0822874a 100644
--- a/security/security.c
+++ b/security/security.c
@@ -892,6 +892,16 @@ int security_inode_copy_up_xattr(const char *name)
 }
 EXPORT_SYMBOL(security_inode_copy_up_xattr);
 
+int security_kernfs_init_security(const struct qstr *qstr,
+				  const struct iattr *dir_iattr,
+				  struct simple_xattrs *dir_secattr,
+				  const struct iattr *iattr,
+				  struct simple_xattrs *secattr)
+{
+	return call_int_hook(kernfs_init_security, 0, qstr, dir_iattr,
+			     dir_secattr, iattr, secattr);
+}
+
 int security_file_permission(struct file *file, int mask)
 {
 	int ret;
-- 
2.20.1


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v4 4/5] selinux: implement the kernfs_init_security hook
  2019-02-05  8:59 [PATCH v4 0/5] Allow initializing the kernfs node's secctx based on its parent Ondrej Mosnacek
                   ` (2 preceding siblings ...)
  2019-02-05  8:59 ` [PATCH v4 3/5] LSM: add new hook for kernfs node initialization Ondrej Mosnacek
@ 2019-02-05  8:59 ` Ondrej Mosnacek
  2019-02-05  8:59 ` [PATCH v4 5/5] kernfs: initialize security of newly created nodes Ondrej Mosnacek
  4 siblings, 0 replies; 10+ messages in thread
From: Ondrej Mosnacek @ 2019-02-05  8:59 UTC (permalink / raw)
  To: selinux, Paul Moore
  Cc: Stephen Smalley, linux-security-module, Casey Schaufler,
	Greg Kroah-Hartman, Tejun Heo, linux-fsdevel, cgroups,
	Ondrej Mosnacek

The hook applies the same logic as selinux_determine_inode_label(), with
the exception of the super_block handling, which will be enforced on the
actual inodes later by other hooks.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 security/selinux/hooks.c | 62 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 62 insertions(+)

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 758a99d1086e..e013cc02de50 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3354,6 +3354,66 @@ static int selinux_inode_copy_up_xattr(const char *name)
 	return -EOPNOTSUPP;
 }
 
+/* kernfs node operations */
+
+int selinux_kernfs_init_security(const struct qstr *qstr,
+				 const struct iattr *dir_iattr,
+				 struct simple_xattrs *dir_secattr,
+				 const struct iattr *iattr,
+				 struct simple_xattrs *secattr)
+{
+	const struct task_security_struct *tsec = current_security();
+	u32 parent_sid, newsid, clen;
+	int rc;
+	char *context;
+
+	rc = simple_xattr_get(dir_secattr, XATTR_SELINUX_SUFFIX, NULL, 0);
+	if (rc == -ENODATA)
+		return 0;
+	else if (rc < 0)
+		return rc;
+
+	clen = (u32)rc;
+	context = kmalloc(clen, GFP_KERNEL);
+	if (!context)
+		return -ENOMEM;
+
+	rc = simple_xattr_get(dir_secattr, XATTR_SELINUX_SUFFIX, context, clen);
+	if (rc < 0) {
+		kfree(context);
+		return rc;
+	}
+
+	rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid,
+				     GFP_KERNEL);
+	kfree(context);
+	if (rc)
+		return rc;
+
+	if (tsec->create_sid) {
+		newsid = tsec->create_sid;
+	} else {
+		u16 secclass = inode_mode_to_security_class(iattr->ia_mode);
+
+		rc = security_transition_sid(&selinux_state, tsec->sid,
+					     parent_sid, secclass, qstr,
+					     &newsid);
+		if (rc)
+			return rc;
+	}
+
+	rc = security_sid_to_context_force(&selinux_state, newsid,
+					   &context, &clen);
+	if (rc)
+		return rc;
+
+	rc = simple_xattr_set(secattr, XATTR_SELINUX_SUFFIX, context, clen,
+			      XATTR_CREATE);
+	kfree(context);
+	return rc;
+}
+
+
 /* file security operations */
 
 static int selinux_revalidate_file_permission(struct file *file, int mask)
@@ -6800,6 +6860,8 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
 	LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
 
+	LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
+
 	LSM_HOOK_INIT(file_permission, selinux_file_permission),
 	LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
 	LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
-- 
2.20.1


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v4 5/5] kernfs: initialize security of newly created nodes
  2019-02-05  8:59 [PATCH v4 0/5] Allow initializing the kernfs node's secctx based on its parent Ondrej Mosnacek
                   ` (3 preceding siblings ...)
  2019-02-05  8:59 ` [PATCH v4 4/5] selinux: implement the kernfs_init_security hook Ondrej Mosnacek
@ 2019-02-05  8:59 ` Ondrej Mosnacek
  2019-02-05 10:18   ` kbuild test robot
  4 siblings, 1 reply; 10+ messages in thread
From: Ondrej Mosnacek @ 2019-02-05  8:59 UTC (permalink / raw)
  To: selinux, Paul Moore
  Cc: Stephen Smalley, linux-security-module, Casey Schaufler,
	Greg Kroah-Hartman, Tejun Heo, linux-fsdevel, cgroups,
	Ondrej Mosnacek

Use the new security_kernfs_init_security() hook to allow LSMs to
possibly assign a non-default security context to a newly created kernfs
node based on the attributes of the new node and also its parent node.

This fixes an issue with cgroupfs under SELinux, where newly created
cgroup subdirectories/files would not inherit its parent's context if
it had been set explicitly to a non-default value (other than the genfs
context specified by the policy). This can be reproduced as follows (on
Fedora/RHEL):

    # mkdir /sys/fs/cgroup/unified/test
    # # Need permissive to change the label under Fedora policy:
    # setenforce 0
    # chcon -t container_file_t /sys/fs/cgroup/unified/test
    # ls -lZ /sys/fs/cgroup/unified
    total 0
    -r--r--r--.  1 root root system_u:object_r:cgroup_t:s0         0 Jan 29 03:06 cgroup.controllers
    -rw-r--r--.  1 root root system_u:object_r:cgroup_t:s0         0 Jan 29 03:06 cgroup.max.depth
    -rw-r--r--.  1 root root system_u:object_r:cgroup_t:s0         0 Jan 29 03:06 cgroup.max.descendants
    -rw-r--r--.  1 root root system_u:object_r:cgroup_t:s0         0 Jan 29 03:06 cgroup.procs
    -r--r--r--.  1 root root system_u:object_r:cgroup_t:s0         0 Jan 29 03:06 cgroup.stat
    -rw-r--r--.  1 root root system_u:object_r:cgroup_t:s0         0 Jan 29 03:06 cgroup.subtree_control
    -rw-r--r--.  1 root root system_u:object_r:cgroup_t:s0         0 Jan 29 03:06 cgroup.threads
    drwxr-xr-x.  2 root root system_u:object_r:cgroup_t:s0         0 Jan 29 03:06 init.scope
    drwxr-xr-x. 26 root root system_u:object_r:cgroup_t:s0         0 Jan 29 03:21 system.slice
    drwxr-xr-x.  3 root root system_u:object_r:container_file_t:s0 0 Jan 29 03:15 test
    drwxr-xr-x.  3 root root system_u:object_r:cgroup_t:s0         0 Jan 29 03:06 user.slice
    # mkdir /sys/fs/cgroup/unified/test/subdir

Actual result:

    # ls -ldZ /sys/fs/cgroup/unified/test/subdir
    drwxr-xr-x. 2 root root system_u:object_r:cgroup_t:s0 0 Jan 29 03:15 /sys/fs/cgroup/unified/test/subdir

Expected result:

    # ls -ldZ /sys/fs/cgroup/unified/test/subdir
    drwxr-xr-x. 2 root root unconfined_u:object_r:container_file_t:s0 0 Jan 29 03:15 /sys/fs/cgroup/unified/test/subdir

Link: https://github.com/SELinuxProject/selinux-kernel/issues/39
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 fs/kernfs/dir.c             | 57 +++++++++++++++++++++++++++++++++++--
 fs/kernfs/inode.c           | 25 +++++++++-------
 fs/kernfs/kernfs-internal.h |  2 ++
 include/linux/xattr.h       | 15 ++++++++++
 4 files changed, 86 insertions(+), 13 deletions(-)

diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index ad7e3356bcc5..735a6d382d9d 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -15,6 +15,7 @@
 #include <linux/slab.h>
 #include <linux/security.h>
 #include <linux/hash.h>
+#include <linux/stringhash.h>
 
 #include "kernfs-internal.h"
 
@@ -616,7 +617,53 @@ struct kernfs_node *kernfs_node_from_dentry(struct dentry *dentry)
 	return NULL;
 }
 
+static int kernfs_node_init_security(struct kernfs_node *parent,
+				     struct kernfs_node *kn)
+{
+	struct simple_xattrs xattr_child, xattr_parent, *pxattr_parent;
+	struct iattr iattr_child, iattr_parent, *piattr_parent;
+	struct qstr q;
+	int ret;
+
+	if (!parent->iattr) {
+		kernfs_iattr_init(&iattr_parent, parent);
+		simple_xattrs_init(&xattr_parent);
+		piattr_parent = &iattr_parent;
+		pxattr_parent = &xattr_parent;
+	} else {
+		piattr_parent = &parent->iattr->ia_iattr;
+		pxattr_parent = &parent->iattr->xattrs_security;
+	}
+
+	kernfs_iattr_init(&iattr_child, kn);
+	simple_xattrs_init(&xattr_child);
+
+	q.name = kn->name;
+	q.hash_len = hashlen_string(parent, kn->name);
+
+	ret = security_kernfs_init_security(&q, piattr_parent, pxattr_parent,
+					    &iattr_child, &xattr_child);
+	if (pxattr_parent == &xattr_parent)
+		simple_xattrs_free(&xattr_parent);
+	if (!ret && !simple_xattrs_empty(&xattr_child)) {
+		/*
+		 * Child has new security xattrs, allocate its kernfs_iattrs
+		 * and put our local xattrs in there.
+		 */
+		struct kernfs_iattrs *attrs = kernfs_iattrs(kn);
+
+		if (!attrs) {
+			simple_xattrs_free(&xattr_child);
+			return -ENOMEM;
+		}
+		simple_xattrs_move(&attrs->xattrs_security, &xattr_child);
+	}
+	simple_xattrs_free(&xattr_child);
+	return ret;
+}
+
 static struct kernfs_node *__kernfs_new_node(struct kernfs_root *root,
+					     struct kernfs_node *parent,
 					     const char *name, umode_t mode,
 					     kuid_t uid, kgid_t gid,
 					     unsigned flags)
@@ -673,6 +720,12 @@ static struct kernfs_node *__kernfs_new_node(struct kernfs_root *root,
 			goto err_out3;
 	}
 
+	if (parent) {
+		ret = kernfs_node_init_security(parent, kn);
+		if (ret)
+			goto err_out3;
+	}
+
 	return kn;
 
  err_out3:
@@ -691,7 +744,7 @@ struct kernfs_node *kernfs_new_node(struct kernfs_node *parent,
 {
 	struct kernfs_node *kn;
 
-	kn = __kernfs_new_node(kernfs_root(parent),
+	kn = __kernfs_new_node(kernfs_root(parent), parent,
 			       name, mode, uid, gid, flags);
 	if (kn) {
 		kernfs_get(parent);
@@ -961,7 +1014,7 @@ struct kernfs_root *kernfs_create_root(struct kernfs_syscall_ops *scops,
 	INIT_LIST_HEAD(&root->supers);
 	root->next_generation = 1;
 
-	kn = __kernfs_new_node(root, "", S_IFDIR | S_IRUGO | S_IXUGO,
+	kn = __kernfs_new_node(root, NULL, "", S_IFDIR | S_IRUGO | S_IXUGO,
 			       GLOBAL_ROOT_UID, GLOBAL_ROOT_GID,
 			       KERNFS_DIR);
 	if (!kn) {
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index f0e2cb4379c0..6a9084aecbe5 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -31,11 +31,22 @@ static const struct inode_operations kernfs_iops = {
 	.listxattr	= kernfs_iop_listxattr,
 };
 
-static struct kernfs_iattrs *kernfs_iattrs(struct kernfs_node *kn)
+void kernfs_iattr_init(struct iattr *iattrs, struct kernfs_node *kn)
+{
+	/* assign default attributes */
+	iattrs->ia_mode = kn->mode;
+	iattrs->ia_uid = GLOBAL_ROOT_UID;
+	iattrs->ia_gid = GLOBAL_ROOT_GID;
+
+	ktime_get_real_ts64(&iattrs->ia_atime);
+	iattrs->ia_mtime = iattrs->ia_atime;
+	iattrs->ia_ctime = iattrs->ia_atime;
+}
+
+struct kernfs_iattrs *kernfs_iattrs(struct kernfs_node *kn)
 {
 	static DEFINE_MUTEX(iattr_mutex);
 	struct kernfs_iattrs *ret;
-	struct iattr *iattrs;
 
 	mutex_lock(&iattr_mutex);
 
@@ -45,16 +56,8 @@ static struct kernfs_iattrs *kernfs_iattrs(struct kernfs_node *kn)
 	kn->iattr = kzalloc(sizeof(struct kernfs_iattrs), GFP_KERNEL);
 	if (!kn->iattr)
 		goto out_unlock;
-	iattrs = &kn->iattr->ia_iattr;
-
-	/* assign default attributes */
-	iattrs->ia_mode = kn->mode;
-	iattrs->ia_uid = GLOBAL_ROOT_UID;
-	iattrs->ia_gid = GLOBAL_ROOT_GID;
 
-	ktime_get_real_ts64(&iattrs->ia_atime);
-	iattrs->ia_mtime = iattrs->ia_atime;
-	iattrs->ia_ctime = iattrs->ia_atime;
+	kernfs_iattr_init(&kn->iattr->ia_iattr, kn);
 
 	simple_xattrs_init(&kn->iattr->xattrs_trusted);
 	simple_xattrs_init(&kn->iattr->xattrs_security);
diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h
index 93bf1dcd0306..ad80f438d8d4 100644
--- a/fs/kernfs/kernfs-internal.h
+++ b/fs/kernfs/kernfs-internal.h
@@ -90,6 +90,8 @@ int kernfs_iop_getattr(const struct path *path, struct kstat *stat,
 		       u32 request_mask, unsigned int query_flags);
 ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size);
 int __kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr);
+void kernfs_iattr_init(struct iattr *iattrs, struct kernfs_node *kn);
+struct kernfs_iattrs *kernfs_iattrs(struct kernfs_node *kn);
 
 /*
  * dir.c
diff --git a/include/linux/xattr.h b/include/linux/xattr.h
index 6dad031be3c2..05fc6812d554 100644
--- a/include/linux/xattr.h
+++ b/include/linux/xattr.h
@@ -108,4 +108,19 @@ ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs, cha
 void simple_xattr_list_add(struct simple_xattrs *xattrs,
 			   struct simple_xattr *new_xattr);
 
+static inline int simple_xattrs_empty(struct simple_xattrs *xattrs)
+{
+	return list_empty(&xattrs->head);
+}
+
+/**
+ * Move the xattr list from @src to @dst, leaving @src empty.
+ */
+static inline void simple_xattrs_move(struct simple_xattrs *dst,
+				      struct simple_xattrs *src)
+{
+	simple_xattrs_free(dst);
+	list_replace_init(&src->head, &dst->head);
+}
+
 #endif	/* _LINUX_XATTR_H */
-- 
2.20.1


^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v4 3/5] LSM: add new hook for kernfs node initialization
  2019-02-05  8:59 ` [PATCH v4 3/5] LSM: add new hook for kernfs node initialization Ondrej Mosnacek
@ 2019-02-05  9:51   ` kbuild test robot
  2019-02-05 11:10     ` Ondrej Mosnacek
  2019-02-05 10:25   ` kbuild test robot
  1 sibling, 1 reply; 10+ messages in thread
From: kbuild test robot @ 2019-02-05  9:51 UTC (permalink / raw)
  To: Ondrej Mosnacek
  Cc: kbuild-all, selinux, Paul Moore, Stephen Smalley,
	linux-security-module, Casey Schaufler, Greg Kroah-Hartman,
	Tejun Heo, linux-fsdevel, cgroups, Ondrej Mosnacek

[-- Attachment #1: Type: text/plain, Size: 1559 bytes --]

Hi Ondrej,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on driver-core/driver-core-testing]
[also build test ERROR on v5.0-rc4 next-20190205]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Ondrej-Mosnacek/Allow-initializing-the-kernfs-node-s-secctx-based-on-its-parent/20190205-171434
config: x86_64-randconfig-x013-201905 (attached as .config)
compiler: gcc-8 (Debian 8.2.0-14) 8.2.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All errors (new ones prefixed by >>):

   In file included from fs/file_table.c:15:
>> include/linux/security.h:796:1: error: expected identifier or '(' before '{' token
    {
    ^
   In file included from fs/file_table.c:15:
   include/linux/security.h:792:19: warning: 'security_kernfs_init_security' declared 'static' but never defined [-Wunused-function]
    static inline int security_kernfs_init_security(
                      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

vim +796 include/linux/security.h

   791	
   792	static inline int security_kernfs_init_security(
   793			const struct qstr *qstr, const struct iattr *dir_iattr,
   794			struct simple_xattrs *dir_secattr, const struct iattr *iattr,
   795			struct simple_xattrs *secattr);
 > 796	{
   797		return 0;
   798	}
   799	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 28315 bytes --]

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v4 5/5] kernfs: initialize security of newly created nodes
  2019-02-05  8:59 ` [PATCH v4 5/5] kernfs: initialize security of newly created nodes Ondrej Mosnacek
@ 2019-02-05 10:18   ` kbuild test robot
  0 siblings, 0 replies; 10+ messages in thread
From: kbuild test robot @ 2019-02-05 10:18 UTC (permalink / raw)
  To: Ondrej Mosnacek
  Cc: kbuild-all, selinux, Paul Moore, Stephen Smalley,
	linux-security-module, Casey Schaufler, Greg Kroah-Hartman,
	Tejun Heo, linux-fsdevel, cgroups, Ondrej Mosnacek

[-- Attachment #1: Type: text/plain, Size: 2083 bytes --]

Hi Ondrej,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on driver-core/driver-core-testing]
[also build test WARNING on v5.0-rc4 next-20190205]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Ondrej-Mosnacek/Allow-initializing-the-kernfs-node-s-secctx-based-on-its-parent/20190205-171434
config: x86_64-randconfig-x013-201905 (attached as .config)
compiler: gcc-8 (Debian 8.2.0-14) 8.2.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All warnings (new ones prefixed by >>):

   In file included from fs/kernfs/dir.c:16:
   include/linux/security.h:796:1: error: expected identifier or '(' before '{' token
    {
    ^
>> include/linux/security.h:792:19: warning: 'security_kernfs_init_security' used but never defined
    static inline int security_kernfs_init_security(
                      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

vim +/security_kernfs_init_security +792 include/linux/security.h

d8ad8b49 Vivek Goyal     2016-07-13  791  
42221e5e Ondrej Mosnacek 2019-02-05 @792  static inline int security_kernfs_init_security(
42221e5e Ondrej Mosnacek 2019-02-05  793  		const struct qstr *qstr, const struct iattr *dir_iattr,
42221e5e Ondrej Mosnacek 2019-02-05  794  		struct simple_xattrs *dir_secattr, const struct iattr *iattr,
42221e5e Ondrej Mosnacek 2019-02-05  795  		struct simple_xattrs *secattr);
42221e5e Ondrej Mosnacek 2019-02-05 @796  {
42221e5e Ondrej Mosnacek 2019-02-05  797  	return 0;
42221e5e Ondrej Mosnacek 2019-02-05  798  }
42221e5e Ondrej Mosnacek 2019-02-05  799  

:::::: The code at line 792 was first introduced by commit
:::::: 42221e5e86c5c3352de02eeb388cef953cdde4a0 LSM: add new hook for kernfs node initialization

:::::: TO: Ondrej Mosnacek <omosnace@redhat.com>
:::::: CC: 0day robot <lkp@intel.com>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 28315 bytes --]

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v4 3/5] LSM: add new hook for kernfs node initialization
  2019-02-05  8:59 ` [PATCH v4 3/5] LSM: add new hook for kernfs node initialization Ondrej Mosnacek
  2019-02-05  9:51   ` kbuild test robot
@ 2019-02-05 10:25   ` kbuild test robot
  1 sibling, 0 replies; 10+ messages in thread
From: kbuild test robot @ 2019-02-05 10:25 UTC (permalink / raw)
  To: Ondrej Mosnacek
  Cc: kbuild-all, selinux, Paul Moore, Stephen Smalley,
	linux-security-module, Casey Schaufler, Greg Kroah-Hartman,
	Tejun Heo, linux-fsdevel, cgroups, Ondrej Mosnacek

[-- Attachment #1: Type: text/plain, Size: 1990 bytes --]

Hi Ondrej,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on driver-core/driver-core-testing]
[also build test ERROR on v5.0-rc4 next-20190205]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Ondrej-Mosnacek/Allow-initializing-the-kernfs-node-s-secctx-based-on-its-parent/20190205-171434
config: sparc-defconfig (attached as .config)
compiler: sparc-linux-gcc (GCC) 8.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        GCC_VERSION=8.2.0 make.cross ARCH=sparc 

All errors (new ones prefixed by >>):

   In file included from include/net/scm.h:8,
                    from include/linux/netlink.h:9,
                    from include/uapi/linux/neighbour.h:6,
                    from include/linux/netdevice.h:50,
                    from include/linux/etherdevice.h:26,
                    from arch/sparc/kernel/idprom.c:13:
   include/linux/security.h:796:1: error: expected identifier or '(' before '{' token
    {
    ^
>> include/linux/security.h:792:19: error: 'security_kernfs_init_security' declared 'static' but never defined [-Werror=unused-function]
    static inline int security_kernfs_init_security(
                      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   cc1: all warnings being treated as errors

vim +792 include/linux/security.h

   791	
 > 792	static inline int security_kernfs_init_security(
   793			const struct qstr *qstr, const struct iattr *dir_iattr,
   794			struct simple_xattrs *dir_secattr, const struct iattr *iattr,
   795			struct simple_xattrs *secattr);
 > 796	{
   797		return 0;
   798	}
   799	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 11972 bytes --]

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v4 3/5] LSM: add new hook for kernfs node initialization
  2019-02-05  9:51   ` kbuild test robot
@ 2019-02-05 11:10     ` Ondrej Mosnacek
  0 siblings, 0 replies; 10+ messages in thread
From: Ondrej Mosnacek @ 2019-02-05 11:10 UTC (permalink / raw)
  To: kbuild test robot
  Cc: kbuild-all, selinux, Paul Moore, Stephen Smalley,
	Linux Security Module list, Casey Schaufler, Greg Kroah-Hartman,
	Tejun Heo, linux-fsdevel, cgroups

On Tue, Feb 5, 2019 at 10:52 AM kbuild test robot <lkp@intel.com> wrote:
>
> Hi Ondrej,
>
> Thank you for the patch! Yet something to improve:
>
> [auto build test ERROR on driver-core/driver-core-testing]
> [also build test ERROR on v5.0-rc4 next-20190205]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>
> url:    https://github.com/0day-ci/linux/commits/Ondrej-Mosnacek/Allow-initializing-the-kernfs-node-s-secctx-based-on-its-parent/20190205-171434
> config: x86_64-randconfig-x013-201905 (attached as .config)
> compiler: gcc-8 (Debian 8.2.0-14) 8.2.0
> reproduce:
>         # save the attached .config to linux build tree
>         make ARCH=x86_64
>
> All errors (new ones prefixed by >>):
>
>    In file included from fs/file_table.c:15:
> >> include/linux/security.h:796:1: error: expected identifier or '(' before '{' token
>     {
>     ^
>    In file included from fs/file_table.c:15:
>    include/linux/security.h:792:19: warning: 'security_kernfs_init_security' declared 'static' but never defined [-Wunused-function]
>     static inline int security_kernfs_init_security(
>                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> vim +796 include/linux/security.h
>
>    791
>    792  static inline int security_kernfs_init_security(
>    793                  const struct qstr *qstr, const struct iattr *dir_iattr,
>    794                  struct simple_xattrs *dir_secattr, const struct iattr *iattr,
>    795                  struct simple_xattrs *secattr);
>  > 796  {
>    797          return 0;
>    798  }
>    799

*facepalm*... Fixed in v5.


-- 
Ondrej Mosnacek <omosnace at redhat dot com>
Associate Software Engineer, Security Technologies
Red Hat, Inc.

^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, back to index

Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-02-05  8:59 [PATCH v4 0/5] Allow initializing the kernfs node's secctx based on its parent Ondrej Mosnacek
2019-02-05  8:59 ` [PATCH v4 1/5] selinux: try security xattr after genfs for kernfs filesystems Ondrej Mosnacek
2019-02-05  8:59 ` [PATCH v4 2/5] kernfs: use simple_xattrs for security attributes Ondrej Mosnacek
2019-02-05  8:59 ` [PATCH v4 3/5] LSM: add new hook for kernfs node initialization Ondrej Mosnacek
2019-02-05  9:51   ` kbuild test robot
2019-02-05 11:10     ` Ondrej Mosnacek
2019-02-05 10:25   ` kbuild test robot
2019-02-05  8:59 ` [PATCH v4 4/5] selinux: implement the kernfs_init_security hook Ondrej Mosnacek
2019-02-05  8:59 ` [PATCH v4 5/5] kernfs: initialize security of newly created nodes Ondrej Mosnacek
2019-02-05 10:18   ` kbuild test robot

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