LSM: shrink sizeof LSM specific portion of common_audit_data

Linus found that the gigantic size of the common audit data caused a big
perf hit on something as simple as running stat() in a loop.  This patch
requires LSMs to declare the LSM specific portion separately rather than
doing it in a union.  Thus each LSM can be responsible for shrinking their
portion and don't have to pay a penalty just because other LSMs have a
bigger space requirement.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 28482f9..3861ce4 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1420,6 +1420,7 @@
 			       int cap, int audit)
 {
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	struct av_decision avd;
 	u16 sclass;
 	u32 sid = cred_sid(cred);
@@ -1427,6 +1428,7 @@
 	int rc;
 
 	COMMON_AUDIT_DATA_INIT(&ad, CAP);
+	ad.selinux_audit_data = &sad;
 	ad.tsk = current;
 	ad.u.cap = cap;
 
@@ -1492,9 +1494,11 @@
 				unsigned flags)
 {
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 
 	COMMON_AUDIT_DATA_INIT(&ad, INODE);
 	ad.u.inode = inode;
+	ad.selinux_audit_data = &sad;
 	return inode_has_perm(cred, inode, perms, &ad, flags);
 }
 
@@ -1507,9 +1511,11 @@
 {
 	struct inode *inode = dentry->d_inode;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 
 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
 	ad.u.dentry = dentry;
+	ad.selinux_audit_data = &sad;
 	return inode_has_perm(cred, inode, av, &ad, 0);
 }
 
@@ -1522,9 +1528,11 @@
 {
 	struct inode *inode = path->dentry->d_inode;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 
 	COMMON_AUDIT_DATA_INIT(&ad, PATH);
 	ad.u.path = *path;
+	ad.selinux_audit_data = &sad;
 	return inode_has_perm(cred, inode, av, &ad, 0);
 }
 
@@ -1543,11 +1551,13 @@
 	struct file_security_struct *fsec = file->f_security;
 	struct inode *inode = file->f_path.dentry->d_inode;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 sid = cred_sid(cred);
 	int rc;
 
 	COMMON_AUDIT_DATA_INIT(&ad, PATH);
 	ad.u.path = file->f_path;
+	ad.selinux_audit_data = &sad;
 
 	if (sid != fsec->sid) {
 		rc = avc_has_perm(sid, fsec->sid,
@@ -1577,6 +1587,7 @@
 	struct superblock_security_struct *sbsec;
 	u32 sid, newsid;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	int rc;
 
 	dsec = dir->i_security;
@@ -1587,6 +1598,7 @@
 
 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
 	ad.u.dentry = dentry;
+	ad.selinux_audit_data = &sad;
 
 	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
 			  DIR__ADD_NAME | DIR__SEARCH,
@@ -1631,6 +1643,7 @@
 {
 	struct inode_security_struct *dsec, *isec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 sid = current_sid();
 	u32 av;
 	int rc;
@@ -1640,6 +1653,7 @@
 
 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
 	ad.u.dentry = dentry;
+	ad.selinux_audit_data = &sad;
 
 	av = DIR__SEARCH;
 	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
@@ -1674,6 +1688,7 @@
 {
 	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 sid = current_sid();
 	u32 av;
 	int old_is_dir, new_is_dir;
@@ -1685,6 +1700,7 @@
 	new_dsec = new_dir->i_security;
 
 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
+	ad.selinux_audit_data = &sad;
 
 	ad.u.dentry = old_dentry;
 	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
@@ -1970,6 +1986,7 @@
 	struct task_security_struct *new_tsec;
 	struct inode_security_struct *isec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	struct inode *inode = bprm->file->f_path.dentry->d_inode;
 	int rc;
 
@@ -2009,6 +2026,7 @@
 	}
 
 	COMMON_AUDIT_DATA_INIT(&ad, PATH);
+	ad.selinux_audit_data = &sad;
 	ad.u.path = bprm->file->f_path;
 
 	if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
@@ -2098,6 +2116,7 @@
 					    struct files_struct *files)
 {
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	struct file *file, *devnull = NULL;
 	struct tty_struct *tty;
 	struct fdtable *fdt;
@@ -2135,6 +2154,7 @@
 	/* Revalidate access to inherited open files. */
 
 	COMMON_AUDIT_DATA_INIT(&ad, INODE);
+	ad.selinux_audit_data = &sad;
 
 	spin_lock(&files->file_lock);
 	for (;;) {
@@ -2472,6 +2492,7 @@
 {
 	const struct cred *cred = current_cred();
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	int rc;
 
 	rc = superblock_doinit(sb, data);
@@ -2483,6 +2504,7 @@
 		return 0;
 
 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
+	ad.selinux_audit_data = &sad;
 	ad.u.dentry = sb->s_root;
 	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
 }
@@ -2491,8 +2513,10 @@
 {
 	const struct cred *cred = current_cred();
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 
 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
+	ad.selinux_audit_data = &sad;
 	ad.u.dentry = dentry->d_sb->s_root;
 	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
 }
@@ -2656,6 +2680,7 @@
 {
 	const struct cred *cred = current_cred();
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 perms;
 	bool from_access;
 	unsigned flags = mask & MAY_NOT_BLOCK;
@@ -2668,10 +2693,11 @@
 		return 0;
 
 	COMMON_AUDIT_DATA_INIT(&ad, INODE);
+	ad.selinux_audit_data = &sad;
 	ad.u.inode = inode;
 
 	if (from_access)
-		ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
+		ad.selinux_audit_data->auditdeny |= FILE__AUDIT_ACCESS;
 
 	perms = file_mask_to_av(inode->i_mode, mask);
 
@@ -2737,6 +2763,7 @@
 	struct inode_security_struct *isec = inode->i_security;
 	struct superblock_security_struct *sbsec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 newsid, sid = current_sid();
 	int rc = 0;
 
@@ -2751,6 +2778,7 @@
 		return -EPERM;
 
 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
+	ad.selinux_audit_data = &sad;
 	ad.u.dentry = dentry;
 
 	rc = avc_has_perm(sid, isec->sid, isec->sclass,
@@ -3345,10 +3373,12 @@
 {
 	u32 sid;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 
 	sid = task_sid(current);
 
 	COMMON_AUDIT_DATA_INIT(&ad, KMOD);
+	ad.selinux_audit_data = &sad;
 	ad.u.kmod_name = kmod_name;
 
 	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
@@ -3721,12 +3751,14 @@
 {
 	struct sk_security_struct *sksec = sk->sk_security;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 tsid = task_sid(task);
 
 	if (sksec->sid == SECINITSID_KERNEL)
 		return 0;
 
 	COMMON_AUDIT_DATA_INIT(&ad, NET);
+	ad.selinux_audit_data = &sad;
 	ad.u.net.sk = sk;
 
 	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
@@ -3805,6 +3837,7 @@
 		char *addrp;
 		struct sk_security_struct *sksec = sk->sk_security;
 		struct common_audit_data ad;
+		struct selinux_audit_data sad = {0,};
 		struct sockaddr_in *addr4 = NULL;
 		struct sockaddr_in6 *addr6 = NULL;
 		unsigned short snum;
@@ -3831,6 +3864,7 @@
 				if (err)
 					goto out;
 				COMMON_AUDIT_DATA_INIT(&ad, NET);
+				ad.selinux_audit_data = &sad;
 				ad.u.net.sport = htons(snum);
 				ad.u.net.family = family;
 				err = avc_has_perm(sksec->sid, sid,
@@ -3864,6 +3898,7 @@
 			goto out;
 
 		COMMON_AUDIT_DATA_INIT(&ad, NET);
+		ad.selinux_audit_data = &sad;
 		ad.u.net.sport = htons(snum);
 		ad.u.net.family = family;
 
@@ -3897,6 +3932,7 @@
 	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
 	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
 		struct common_audit_data ad;
+		struct selinux_audit_data sad = {0,};
 		struct sockaddr_in *addr4 = NULL;
 		struct sockaddr_in6 *addr6 = NULL;
 		unsigned short snum;
@@ -3922,6 +3958,7 @@
 		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
 
 		COMMON_AUDIT_DATA_INIT(&ad, NET);
+		ad.selinux_audit_data = &sad;
 		ad.u.net.dport = htons(snum);
 		ad.u.net.family = sk->sk_family;
 		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
@@ -4012,9 +4049,11 @@
 	struct sk_security_struct *sksec_other = other->sk_security;
 	struct sk_security_struct *sksec_new = newsk->sk_security;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	int err;
 
 	COMMON_AUDIT_DATA_INIT(&ad, NET);
+	ad.selinux_audit_data = &sad;
 	ad.u.net.sk = other;
 
 	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
@@ -4042,8 +4081,10 @@
 	struct sk_security_struct *ssec = sock->sk->sk_security;
 	struct sk_security_struct *osec = other->sk->sk_security;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 
 	COMMON_AUDIT_DATA_INIT(&ad, NET);
+	ad.selinux_audit_data = &sad;
 	ad.u.net.sk = other->sk;
 
 	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
@@ -4080,9 +4121,11 @@
 	struct sk_security_struct *sksec = sk->sk_security;
 	u32 sk_sid = sksec->sid;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	char *addrp;
 
 	COMMON_AUDIT_DATA_INIT(&ad, NET);
+	ad.selinux_audit_data = &sad;
 	ad.u.net.netif = skb->skb_iif;
 	ad.u.net.family = family;
 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
@@ -4111,6 +4154,7 @@
 	u16 family = sk->sk_family;
 	u32 sk_sid = sksec->sid;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	char *addrp;
 	u8 secmark_active;
 	u8 peerlbl_active;
@@ -4135,6 +4179,7 @@
 		return 0;
 
 	COMMON_AUDIT_DATA_INIT(&ad, NET);
+	ad.selinux_audit_data = &sad;
 	ad.u.net.netif = skb->skb_iif;
 	ad.u.net.family = family;
 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
@@ -4471,6 +4516,7 @@
 	char *addrp;
 	u32 peer_sid;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u8 secmark_active;
 	u8 netlbl_active;
 	u8 peerlbl_active;
@@ -4488,6 +4534,7 @@
 		return NF_DROP;
 
 	COMMON_AUDIT_DATA_INIT(&ad, NET);
+	ad.selinux_audit_data = &sad;
 	ad.u.net.netif = ifindex;
 	ad.u.net.family = family;
 	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
@@ -4576,6 +4623,7 @@
 	struct sock *sk = skb->sk;
 	struct sk_security_struct *sksec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	char *addrp;
 	u8 proto;
 
@@ -4584,6 +4632,7 @@
 	sksec = sk->sk_security;
 
 	COMMON_AUDIT_DATA_INIT(&ad, NET);
+	ad.selinux_audit_data = &sad;
 	ad.u.net.netif = ifindex;
 	ad.u.net.family = family;
 	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
@@ -4607,6 +4656,7 @@
 	u32 peer_sid;
 	struct sock *sk;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	char *addrp;
 	u8 secmark_active;
 	u8 peerlbl_active;
@@ -4653,6 +4703,7 @@
 	}
 
 	COMMON_AUDIT_DATA_INIT(&ad, NET);
+	ad.selinux_audit_data = &sad;
 	ad.u.net.netif = ifindex;
 	ad.u.net.family = family;
 	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
@@ -4769,11 +4820,13 @@
 {
 	struct ipc_security_struct *isec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 sid = current_sid();
 
 	isec = ipc_perms->security;
 
 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
+	ad.selinux_audit_data = &sad;
 	ad.u.ipc_id = ipc_perms->key;
 
 	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
@@ -4794,6 +4847,7 @@
 {
 	struct ipc_security_struct *isec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 sid = current_sid();
 	int rc;
 
@@ -4804,6 +4858,7 @@
 	isec = msq->q_perm.security;
 
 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
+	ad.selinux_audit_data = &sad;
 	ad.u.ipc_id = msq->q_perm.key;
 
 	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
@@ -4824,11 +4879,13 @@
 {
 	struct ipc_security_struct *isec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 sid = current_sid();
 
 	isec = msq->q_perm.security;
 
 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
+	ad.selinux_audit_data = &sad;
 	ad.u.ipc_id = msq->q_perm.key;
 
 	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
@@ -4868,6 +4925,7 @@
 	struct ipc_security_struct *isec;
 	struct msg_security_struct *msec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 sid = current_sid();
 	int rc;
 
@@ -4889,6 +4947,7 @@
 	}
 
 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
+	ad.selinux_audit_data = &sad;
 	ad.u.ipc_id = msq->q_perm.key;
 
 	/* Can this process write to the queue? */
@@ -4913,6 +4972,7 @@
 	struct ipc_security_struct *isec;
 	struct msg_security_struct *msec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 sid = task_sid(target);
 	int rc;
 
@@ -4920,6 +4980,7 @@
 	msec = msg->security;
 
 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
+	ad.selinux_audit_data = &sad;
 	ad.u.ipc_id = msq->q_perm.key;
 
 	rc = avc_has_perm(sid, isec->sid,
@@ -4935,6 +4996,7 @@
 {
 	struct ipc_security_struct *isec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 sid = current_sid();
 	int rc;
 
@@ -4945,6 +5007,7 @@
 	isec = shp->shm_perm.security;
 
 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
+	ad.selinux_audit_data = &sad;
 	ad.u.ipc_id = shp->shm_perm.key;
 
 	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
@@ -4965,11 +5028,13 @@
 {
 	struct ipc_security_struct *isec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 sid = current_sid();
 
 	isec = shp->shm_perm.security;
 
 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
+	ad.selinux_audit_data = &sad;
 	ad.u.ipc_id = shp->shm_perm.key;
 
 	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
@@ -5027,6 +5092,7 @@
 {
 	struct ipc_security_struct *isec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 sid = current_sid();
 	int rc;
 
@@ -5037,6 +5103,7 @@
 	isec = sma->sem_perm.security;
 
 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
+	ad.selinux_audit_data = &sad;
 	ad.u.ipc_id = sma->sem_perm.key;
 
 	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
@@ -5057,11 +5124,13 @@
 {
 	struct ipc_security_struct *isec;
 	struct common_audit_data ad;
+	struct selinux_audit_data sad = {0,};
 	u32 sid = current_sid();
 
 	isec = sma->sem_perm.security;
 
 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
+	ad.selinux_audit_data = &sad;
 	ad.u.ipc_id = sma->sem_perm.key;
 
 	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,