[PATCH v5 31/38] SELinux: Abstract use of inode security blob
From: Casey Schaufler
Date: Mon Nov 26 2018 - 18:51:46 EST
Don't use the inode->i_security pointer directly.
Provide a helper function that provides the security blob pointer.
Signed-off-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
security/selinux/hooks.c | 26 +++++++++++++-------------
security/selinux/include/objsec.h | 6 ++++++
security/selinux/selinuxfs.c | 4 ++--
3 files changed, 21 insertions(+), 15 deletions(-)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 9669a059ce0f..3069e95d86e6 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -272,7 +272,7 @@ static int __inode_security_revalidate(struct inode *inode,
struct dentry *dentry,
bool may_sleep)
{
- struct inode_security_struct *isec = inode->i_security;
+ struct inode_security_struct *isec = selinux_inode(inode);
might_sleep_if(may_sleep);
@@ -293,7 +293,7 @@ static int __inode_security_revalidate(struct inode *inode,
static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
{
- return inode->i_security;
+ return selinux_inode(inode);
}
static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
@@ -303,7 +303,7 @@ static struct inode_security_struct *inode_security_rcu(struct inode *inode, boo
error = __inode_security_revalidate(inode, NULL, !rcu);
if (error)
return ERR_PTR(error);
- return inode->i_security;
+ return selinux_inode(inode);
}
/*
@@ -312,14 +312,14 @@ static struct inode_security_struct *inode_security_rcu(struct inode *inode, boo
static struct inode_security_struct *inode_security(struct inode *inode)
{
__inode_security_revalidate(inode, NULL, true);
- return inode->i_security;
+ return selinux_inode(inode);
}
static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
{
struct inode *inode = d_backing_inode(dentry);
- return inode->i_security;
+ return selinux_inode(inode);
}
/*
@@ -330,7 +330,7 @@ static struct inode_security_struct *backing_inode_security(struct dentry *dentr
struct inode *inode = d_backing_inode(dentry);
__inode_security_revalidate(inode, dentry, true);
- return inode->i_security;
+ return selinux_inode(inode);
}
static void inode_free_rcu(struct rcu_head *head)
@@ -343,7 +343,7 @@ static void inode_free_rcu(struct rcu_head *head)
static void inode_free_security(struct inode *inode)
{
- struct inode_security_struct *isec = inode->i_security;
+ struct inode_security_struct *isec = selinux_inode(inode);
struct superblock_security_struct *sbsec = inode->i_sb->s_security;
/*
@@ -1502,7 +1502,7 @@ static int selinux_genfs_get_sid(struct dentry *dentry,
static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
{
struct superblock_security_struct *sbsec = NULL;
- struct inode_security_struct *isec = inode->i_security;
+ struct inode_security_struct *isec = selinux_inode(inode);
u32 task_sid, sid = 0;
u16 sclass;
struct dentry *dentry;
@@ -1802,7 +1802,7 @@ static int inode_has_perm(const struct cred *cred,
return 0;
sid = cred_sid(cred);
- isec = inode->i_security;
+ isec = selinux_inode(inode);
return avc_has_perm(&selinux_state,
sid, isec->sid, isec->sclass, perms, adp);
@@ -3030,7 +3030,7 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
/* Possibly defer initialization to selinux_complete_init. */
if (sbsec->flags & SE_SBINITIALIZED) {
- struct inode_security_struct *isec = inode->i_security;
+ struct inode_security_struct *isec = selinux_inode(inode);
isec->sclass = inode_mode_to_security_class(inode->i_mode);
isec->sid = newsid;
isec->initialized = LABEL_INITIALIZED;
@@ -3130,7 +3130,7 @@ static noinline int audit_inode_permission(struct inode *inode,
unsigned flags)
{
struct common_audit_data ad;
- struct inode_security_struct *isec = inode->i_security;
+ struct inode_security_struct *isec = selinux_inode(inode);
int rc;
ad.type = LSM_AUDIT_DATA_INODE;
@@ -4150,7 +4150,7 @@ static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
static void selinux_task_to_inode(struct task_struct *p,
struct inode *inode)
{
- struct inode_security_struct *isec = inode->i_security;
+ struct inode_security_struct *isec = selinux_inode(inode);
u32 sid = task_sid(p);
spin_lock(&isec->lock);
@@ -6529,7 +6529,7 @@ static void selinux_release_secctx(char *secdata, u32 seclen)
static void selinux_inode_invalidate_secctx(struct inode *inode)
{
- struct inode_security_struct *isec = inode->i_security;
+ struct inode_security_struct *isec = selinux_inode(inode);
spin_lock(&isec->lock);
isec->initialized = LABEL_INVALID;
diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h
index 96374dbf4ace..26b4ff6b4d81 100644
--- a/security/selinux/include/objsec.h
+++ b/security/selinux/include/objsec.h
@@ -170,4 +170,10 @@ static inline struct file_security_struct *selinux_file(const struct file *file)
return file->f_security + selinux_blob_sizes.lbs_file;
}
+static inline struct inode_security_struct *selinux_inode(
+ const struct inode *inode)
+{
+ return inode->i_security;
+}
+
#endif /* _SELINUX_OBJSEC_H_ */
diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index f3a5a138a096..145ee62f205a 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -1378,7 +1378,7 @@ static int sel_make_bools(struct selinux_fs_info *fsi)
goto out;
}
- isec = (struct inode_security_struct *)inode->i_security;
+ isec = selinux_inode(inode);
ret = security_genfs_sid(fsi->state, "selinuxfs", page,
SECCLASS_FILE, &sid);
if (ret) {
@@ -1953,7 +1953,7 @@ static int sel_fill_super(struct super_block *sb, void *data, int silent)
}
inode->i_ino = ++fsi->last_ino;
- isec = (struct inode_security_struct *)inode->i_security;
+ isec = selinux_inode(inode);
isec->sid = SECINITSID_DEVNULL;
isec->sclass = SECCLASS_CHR_FILE;
isec->initialized = LABEL_INITIALIZED;
--
2.14.5