LSM: split LSM_AUDIT_DATA_FS into _PATH and _INODE

The lsm common audit code has wacky contortions making sure which pieces
of information are set based on if it was given a path, dentry, or
inode.  Split this into path and inode to get rid of some of the code
complexity.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>

5 files changed, 74 insertions, 68 deletions

diff --git a/security/lsm_audit.c b/security/lsm_audit.c
index 908aa712816a..2e846052cbf4 100644
--- a/security/lsm_audit.c
+++ b/security/lsm_audit.c
@@ -210,7 +210,6 @@ static inline void print_ipv4_addr(struct audit_buffer *ab, __be32 addr,
 static void dump_common_audit_data(struct audit_buffer *ab,
                                    struct common_audit_data *a)
 {
-        struct inode *inode = NULL;
         struct task_struct *tsk = current;
 
         if (a->tsk)
@@ -229,33 +228,40 @@ static void dump_common_audit_data(struct audit_buffer *ab,
         case LSM_AUDIT_DATA_CAP:
                 audit_log_format(ab, " capability=%d ", a->u.cap);
                 break;
-        case LSM_AUDIT_DATA_FS:
-                if (a->u.fs.path.dentry) {
-                        struct dentry *dentry = a->u.fs.path.dentry;
-                        if (a->u.fs.path.mnt) {
-                                audit_log_d_path(ab, "path=", &a->u.fs.path);
-                        } else {
-                                audit_log_format(ab, " name=");
-                                audit_log_untrustedstring(ab,
-                                                 dentry->d_name.name);
-                        }
-                        inode = dentry->d_inode;
-                } else if (a->u.fs.inode) {
-                        struct dentry *dentry;
-                        inode = a->u.fs.inode;
-                        dentry = d_find_alias(inode);
-                        if (dentry) {
-                                audit_log_format(ab, " name=");
-                                audit_log_untrustedstring(ab,
-                                                 dentry->d_name.name);
-                                dput(dentry);
-                        }
+        case LSM_AUDIT_DATA_PATH: {
+                struct dentry *dentry = a->u.path.dentry;
+                struct inode *inode;
+
+                if (a->u.path.mnt) {
+                        audit_log_d_path(ab, "path=", &a->u.path);
+                } else {
+                        audit_log_format(ab, " name=");
+                        audit_log_untrustedstring(ab,
+                                         dentry->d_name.name);
                 }
+                inode = dentry->d_inode;
                 if (inode)
                         audit_log_format(ab, " dev=%s ino=%lu",
                                         inode->i_sb->s_id,
                                         inode->i_ino);
                 break;
+        }
+        case LSM_AUDIT_DATA_INODE: {
+                struct dentry *dentry;
+                struct inode *inode;
+
+                inode = a->u.inode;
+                dentry = d_find_alias(inode);
+                if (dentry) {
+                        audit_log_format(ab, " name=");
+                        audit_log_untrustedstring(ab,
+                                         dentry->d_name.name);
+                        dput(dentry);
+                }
+                audit_log_format(ab, " dev=%s ino=%lu", inode->i_sb->s_id,
+                                 inode->i_ino);
+                break;
+        }
         case LSM_AUDIT_DATA_TASK:
                 tsk = a->u.tsk;
                 if (tsk && tsk->pid) {
diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index 1d027e29ce8d..ce742f1778e1 100644
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -531,7 +531,7 @@ int avc_audit(u32 ssid, u32 tsid,
          * during retry. However this is logically just as if the operation
          * happened a little later.
          */
-        if ((a->type == LSM_AUDIT_DATA_FS) &&
+        if ((a->type == LSM_AUDIT_DATA_INODE) &&
             (flags & IPERM_FLAG_RCU))
                 return -ECHILD;
 
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index ed5f29aa0a38..ad664d3056eb 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1488,8 +1488,8 @@ static int inode_has_perm(const struct cred *cred,
 
         if (!adp) {
                 adp = &ad;
-                COMMON_AUDIT_DATA_INIT(&ad, FS);
-                ad.u.fs.inode = inode;
+                COMMON_AUDIT_DATA_INIT(&ad, INODE);
+                ad.u.inode = inode;
         }
 
         return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
@@ -1506,9 +1506,9 @@ static inline int dentry_has_perm(const struct cred *cred,
         struct inode *inode = dentry->d_inode;
         struct common_audit_data ad;
 
-        COMMON_AUDIT_DATA_INIT(&ad, FS);
-        ad.u.fs.path.mnt = mnt;
-        ad.u.fs.path.dentry = dentry;
+        COMMON_AUDIT_DATA_INIT(&ad, PATH);
+        ad.u.path.mnt = mnt;
+        ad.u.path.dentry = dentry;
         return inode_has_perm(cred, inode, av, &ad, 0);
 }
 
@@ -1530,8 +1530,8 @@ static int file_has_perm(const struct cred *cred,
         u32 sid = cred_sid(cred);
         int rc;
 
-        COMMON_AUDIT_DATA_INIT(&ad, FS);
-        ad.u.fs.path = file->f_path;
+        COMMON_AUDIT_DATA_INIT(&ad, PATH);
+        ad.u.path = file->f_path;
 
         if (sid != fsec->sid) {
                 rc = avc_has_perm(sid, fsec->sid,
@@ -1569,8 +1569,8 @@ static int may_create(struct inode *dir,
         sid = tsec->sid;
         newsid = tsec->create_sid;
 
-        COMMON_AUDIT_DATA_INIT(&ad, FS);
-        ad.u.fs.path.dentry = dentry;
+        COMMON_AUDIT_DATA_INIT(&ad, PATH);
+        ad.u.path.dentry = dentry;
 
         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
                           DIR__ADD_NAME | DIR__SEARCH,
@@ -1621,8 +1621,8 @@ static int may_link(struct inode *dir,
         dsec = dir->i_security;
         isec = dentry->d_inode->i_security;
 
-        COMMON_AUDIT_DATA_INIT(&ad, FS);
-        ad.u.fs.path.dentry = dentry;
+        COMMON_AUDIT_DATA_INIT(&ad, PATH);
+        ad.u.path.dentry = dentry;
 
         av = DIR__SEARCH;
         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
@@ -1667,9 +1667,9 @@ static inline int may_rename(struct inode *old_dir,
         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
         new_dsec = new_dir->i_security;
 
-        COMMON_AUDIT_DATA_INIT(&ad, FS);
+        COMMON_AUDIT_DATA_INIT(&ad, PATH);
 
-        ad.u.fs.path.dentry = old_dentry;
+        ad.u.path.dentry = old_dentry;
         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
         if (rc)
@@ -1685,7 +1685,7 @@ static inline int may_rename(struct inode *old_dir,
                         return rc;
         }
 
-        ad.u.fs.path.dentry = new_dentry;
+        ad.u.path.dentry = new_dentry;
         av = DIR__ADD_NAME | DIR__SEARCH;
         if (new_dentry->d_inode)
                 av |= DIR__REMOVE_NAME;
@@ -1991,8 +1991,8 @@ static int selinux_bprm_set_creds(struct linux_binprm *bprm)
                         return rc;
         }
 
-        COMMON_AUDIT_DATA_INIT(&ad, FS);
-        ad.u.fs.path = bprm->file->f_path;
+        COMMON_AUDIT_DATA_INIT(&ad, PATH);
+        ad.u.path = bprm->file->f_path;
 
         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
                 new_tsec->sid = old_tsec->sid;
@@ -2120,7 +2120,7 @@ static inline void flush_unauthorized_files(const struct cred *cred,
 
         /* Revalidate access to inherited open files. */
 
-        COMMON_AUDIT_DATA_INIT(&ad, FS);
+        COMMON_AUDIT_DATA_INIT(&ad, INODE);
 
         spin_lock(&files->file_lock);
         for (;;) {
@@ -2468,8 +2468,8 @@ static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
         if (flags & MS_KERNMOUNT)
                 return 0;
 
-        COMMON_AUDIT_DATA_INIT(&ad, FS);
-        ad.u.fs.path.dentry = sb->s_root;
+        COMMON_AUDIT_DATA_INIT(&ad, PATH);
+        ad.u.path.dentry = sb->s_root;
         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
 }
 
@@ -2478,8 +2478,8 @@ static int selinux_sb_statfs(struct dentry *dentry)
         const struct cred *cred = current_cred();
         struct common_audit_data ad;
 
-        COMMON_AUDIT_DATA_INIT(&ad, FS);
-        ad.u.fs.path.dentry = dentry->d_sb->s_root;
+        COMMON_AUDIT_DATA_INIT(&ad, PATH);
+        ad.u.path.dentry = dentry->d_sb->s_root;
         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
 }
 
@@ -2653,8 +2653,8 @@ static int selinux_inode_permission(struct inode *inode, int mask, unsigned flag
         if (!mask)
                 return 0;
 
-        COMMON_AUDIT_DATA_INIT(&ad, FS);
-        ad.u.fs.inode = inode;
+        COMMON_AUDIT_DATA_INIT(&ad, INODE);
+        ad.u.inode = inode;
 
         if (from_access)
                 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
@@ -2732,8 +2732,8 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
         if (!is_owner_or_cap(inode))
                 return -EPERM;
 
-        COMMON_AUDIT_DATA_INIT(&ad, FS);
-        ad.u.fs.path.dentry = dentry;
+        COMMON_AUDIT_DATA_INIT(&ad, PATH);
+        ad.u.path.dentry = dentry;
 
         rc = avc_has_perm(sid, isec->sid, isec->sclass,
                           FILE__RELABELFROM, &ad);
diff --git a/security/smack/smack.h b/security/smack/smack.h
index b449cfdad21c..a16925c0e91a 100644
--- a/security/smack/smack.h
+++ b/security/smack/smack.h
@@ -316,22 +316,22 @@ static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a,
 static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a,
                                                     struct dentry *d)
 {
-        a->a.u.fs.path.dentry = d;
+        a->a.u.path.dentry = d;
 }
 static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a,
                                                  struct vfsmount *m)
 {
-        a->a.u.fs.path.mnt = m;
+        a->a.u.path.mnt = m;
 }
 static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a,
                                               struct inode *i)
 {
-        a->a.u.fs.inode = i;
+        a->a.u.inode = i;
 }
 static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a,
                                              struct path p)
 {
-        a->a.u.fs.path = p;
+        a->a.u.path = p;
 }
 static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a,
                                             struct sock *sk)
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 42fcb47747a3..eeb393fbf925 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -383,7 +383,7 @@ static int smack_sb_statfs(struct dentry *dentry)
         int rc;
         struct smk_audit_info ad;
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
         rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
@@ -407,7 +407,7 @@ static int smack_sb_mount(char *dev_name, struct path *path,
         struct superblock_smack *sbp = path->mnt->mnt_sb->s_security;
         struct smk_audit_info ad;
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path(&ad, *path);
 
         return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
@@ -426,7 +426,7 @@ static int smack_sb_umount(struct vfsmount *mnt, int flags)
         struct superblock_smack *sbp;
         struct smk_audit_info ad;
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path_dentry(&ad, mnt->mnt_root);
         smk_ad_setfield_u_fs_path_mnt(&ad, mnt);
 
@@ -563,7 +563,7 @@ static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
         struct smk_audit_info ad;
         int rc;
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
 
         isp = smk_of_inode(old_dentry->d_inode);
@@ -592,7 +592,7 @@ static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
         struct smk_audit_info ad;
         int rc;
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
         /*
@@ -623,7 +623,7 @@ static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
         struct smk_audit_info ad;
         int rc;
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
         /*
@@ -663,7 +663,7 @@ static int smack_inode_rename(struct inode *old_inode,
         char *isp;
         struct smk_audit_info ad;
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
 
         isp = smk_of_inode(old_dentry->d_inode);
@@ -700,7 +700,7 @@ static int smack_inode_permission(struct inode *inode, int mask, unsigned flags)
         /* May be droppable after audit */
         if (flags & IPERM_FLAG_RCU)
                 return -ECHILD;
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
         smk_ad_setfield_u_fs_inode(&ad, inode);
         return smk_curacc(smk_of_inode(inode), mask, &ad);
 }
@@ -720,7 +720,7 @@ static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
          */
         if (iattr->ia_valid & ATTR_FORCE)
                 return 0;
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
         return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
@@ -737,7 +737,7 @@ static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
 {
         struct smk_audit_info ad;
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
         smk_ad_setfield_u_fs_path_mnt(&ad, mnt);
         return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
@@ -784,7 +784,7 @@ static int smack_inode_setxattr(struct dentry *dentry, const char *name,
         } else
                 rc = cap_inode_setxattr(dentry, name, value, size, flags);
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
         if (rc == 0)
@@ -845,7 +845,7 @@ static int smack_inode_getxattr(struct dentry *dentry, const char *name)
 {
         struct smk_audit_info ad;
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
         return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
@@ -877,7 +877,7 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name)
         } else
                 rc = cap_inode_removexattr(dentry, name);
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
         if (rc == 0)
                 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
@@ -1047,7 +1047,7 @@ static int smack_file_ioctl(struct file *file, unsigned int cmd,
         int rc = 0;
         struct smk_audit_info ad;
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path(&ad, file->f_path);
 
         if (_IOC_DIR(cmd) & _IOC_WRITE)
@@ -1070,7 +1070,7 @@ static int smack_file_lock(struct file *file, unsigned int cmd)
 {
         struct smk_audit_info ad;
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path_dentry(&ad, file->f_path.dentry);
         return smk_curacc(file->f_security, MAY_WRITE, &ad);
 }
@@ -1089,7 +1089,7 @@ static int smack_file_fcntl(struct file *file, unsigned int cmd,
         struct smk_audit_info ad;
         int rc;
 
-        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
+        smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path(&ad, file->f_path);
 
         switch (cmd) {