Module Name: src
Committed By: maxv
Date: Sat Apr 25 19:10:29 UTC 2015
Modified Files:
src/sys/kern: kern_veriexec.c
Log Message:
Make veriexec_renamechk() more readable. Also add a KASSERT on vte_count.
No real functional change
To generate a diff of this commit:
cvs rdiff -u -r1.4 -r1.5 src/sys/kern/kern_veriexec.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/kern_veriexec.c
diff -u src/sys/kern/kern_veriexec.c:1.4 src/sys/kern/kern_veriexec.c:1.5
--- src/sys/kern/kern_veriexec.c:1.4 Sat Apr 25 18:43:13 2015
+++ src/sys/kern/kern_veriexec.c Sat Apr 25 19:10:29 2015
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_veriexec.c,v 1.4 2015/04/25 18:43:13 maxv Exp $ */
+/* $NetBSD: kern_veriexec.c,v 1.5 2015/04/25 19:10:29 maxv Exp $ */
/*-
* Copyright (c) 2005, 2006 Elad Efrat <e...@netbsd.org>
@@ -29,7 +29,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_veriexec.c,v 1.4 2015/04/25 18:43:13 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_veriexec.c,v 1.5 2015/04/25 19:10:29 maxv Exp $");
#include "opt_veriexec.h"
@@ -878,7 +878,6 @@ veriexec_removechk(struct lwp *l, struct
return 0;
rw_enter(&veriexec_op_lock, RW_READER);
-
vfe = veriexec_get(vp);
rw_exit(&veriexec_op_lock);
@@ -913,7 +912,7 @@ int
veriexec_renamechk(struct lwp *l, struct vnode *fromvp, const char *fromname,
struct vnode *tovp, const char *toname)
{
- struct veriexec_file_entry *vfe, *tvfe;
+ struct veriexec_file_entry *fvfe = NULL, *tvfe = NULL;
if (veriexec_bypass && (veriexec_strict == VERIEXEC_LEARNING))
return 0;
@@ -924,70 +923,73 @@ veriexec_renamechk(struct lwp *l, struct
log(LOG_ALERT, "Veriexec: Preventing rename of `%s' to "
"`%s', uid=%u, pid=%u: Lockdown mode.\n", fromname, toname,
kauth_cred_geteuid(l->l_cred), l->l_proc->p_pid);
-
rw_exit(&veriexec_op_lock);
return (EPERM);
}
- vfe = veriexec_get(fromvp);
- tvfe = NULL;
+ fvfe = veriexec_get(fromvp);
if (tovp != NULL)
tvfe = veriexec_get(tovp);
- if ((vfe != NULL) || (tvfe != NULL)) {
- if (veriexec_strict >= VERIEXEC_IPS) {
- log(LOG_ALERT, "Veriexec: Preventing rename of `%s' "
- "to `%s', uid=%u, pid=%u: IPS mode, %s "
- "monitored.\n", fromname, toname,
- kauth_cred_geteuid(l->l_cred),
- l->l_proc->p_pid, (vfe != NULL && tvfe != NULL) ?
- "files" : "file");
+ if ((fvfe == NULL) && (tvfe == NULL)) {
+ /* None of them is monitored */
+ rw_exit(&veriexec_op_lock);
+ return 0;
+ }
- rw_exit(&veriexec_op_lock);
- return (EPERM);
- }
+ if (veriexec_strict >= VERIEXEC_IPS) {
+ log(LOG_ALERT, "Veriexec: Preventing rename of `%s' "
+ "to `%s', uid=%u, pid=%u: IPS mode, %s "
+ "monitored.\n", fromname, toname,
+ kauth_cred_geteuid(l->l_cred),
+ l->l_proc->p_pid, (fvfe != NULL && tvfe != NULL) ?
+ "files" : "file");
+ rw_exit(&veriexec_op_lock);
+ return (EPERM);
+ }
+ if (fvfe != NULL) {
/*
* Monitored file is renamed; filename no longer relevant.
- *
+ */
+
+ /*
* XXX: We could keep the buffer, and when (and if) updating the
* XXX: filename post-rename, re-allocate it only if it's not
* XXX: big enough for the new filename.
*/
- if (vfe != NULL) {
- /* XXXX get write lock on vfe here? */
- VERIEXEC_RW_UPGRADE(&veriexec_op_lock);
- /* once we have the op lock in write mode
- * there should be no locks on any file
- * entries so we can destroy the object.
- */
+ /* XXX: Get write lock on fvfe here? */
- if (vfe->filename_len > 0)
- kmem_free(vfe->filename, vfe->filename_len);
+ VERIEXEC_RW_UPGRADE(&veriexec_op_lock);
+ /* once we have the op lock in write mode
+ * there should be no locks on any file
+ * entries so we can destroy the object.
+ */
- vfe->filename = NULL;
- vfe->filename_len = 0;
+ if (fvfe->filename_len > 0)
+ kmem_free(fvfe->filename, fvfe->filename_len);
- rw_downgrade(&veriexec_op_lock);
- }
+ fvfe->filename = NULL;
+ fvfe->filename_len = 0;
- log(LOG_NOTICE, "Veriexec: %s file `%s' renamed to "
- "%s file `%s', uid=%u, pid=%u.\n", (vfe != NULL) ?
- "Monitored" : "Non-monitored", fromname, (tvfe != NULL) ?
- "monitored" : "non-monitored", toname,
- kauth_cred_geteuid(l->l_cred), l->l_proc->p_pid);
+ rw_downgrade(&veriexec_op_lock);
+ }
- rw_exit(&veriexec_op_lock);
+ log(LOG_NOTICE, "Veriexec: %s file `%s' renamed to "
+ "%s file `%s', uid=%u, pid=%u.\n", (fvfe != NULL) ?
+ "Monitored" : "Non-monitored", fromname, (tvfe != NULL) ?
+ "monitored" : "non-monitored", toname,
+ kauth_cred_geteuid(l->l_cred), l->l_proc->p_pid);
+
+ rw_exit(&veriexec_op_lock);
+ if (tvfe != NULL) {
/*
* Monitored file is overwritten. Remove the entry.
*/
- if (tvfe != NULL)
- (void)veriexec_file_delete(l, tovp);
-
- } else
- rw_exit(&veriexec_op_lock);
+ (void)veriexec_file_delete(l, tovp);
+ }
return (0);
}
@@ -1337,7 +1339,8 @@ veriexec_file_add(struct lwp *l, prop_di
}
int
-veriexec_table_delete(struct lwp *l, struct mount *mp) {
+veriexec_table_delete(struct lwp *l, struct mount *mp)
+{
struct veriexec_table_entry *vte;
vte = veriexec_table_lookup(mp);
@@ -1351,7 +1354,8 @@ veriexec_table_delete(struct lwp *l, str
}
int
-veriexec_file_delete(struct lwp *l, struct vnode *vp) {
+veriexec_file_delete(struct lwp *l, struct vnode *vp)
+{
struct veriexec_table_entry *vte;
int error;
@@ -1362,8 +1366,10 @@ veriexec_file_delete(struct lwp *l, stru
rw_enter(&veriexec_op_lock, RW_WRITER);
error = fileassoc_clear(vp, veriexec_hook);
rw_exit(&veriexec_op_lock);
- if (!error)
+ if (!error) {
+ KASSERT(vte->vte_count > 0);
vte->vte_count--;
+ }
return (error);
}
