[PATCH] Collect more inode information during syscall processing.
This patch augments the collection of inode info during syscall
processing. It represents part of the functionality that was provided
by the auditfs patch included in RHEL4.
Specifically, it:
- Collects information for target inodes created or removed during
syscalls. Previous code only collects information for the target
inode's parent.
- Adds the audit_inode() hook to syscalls that operate on a file
descriptor (e.g. fchown), enabling audit to do inode filtering for
these calls.
- Modifies filtering code to check audit context for either an inode #
or a parent inode # matching a given rule.
- Modifies logging to provide inode # for both parent and child.
- Protect debug info from NULL audit_names.name.
[AV: folded a later typo fix from the same author]
Signed-off-by: Amy Griffis <amy.griffis@hp.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namei.c b/fs/namei.c
index f6619af..51cfc9c 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1353,6 +1353,7 @@
return -ENOENT;
BUG_ON(victim->d_parent->d_inode != dir);
+ audit_inode_child(victim->d_name.name, victim->d_inode, dir->i_ino);
error = permission(dir,MAY_WRITE | MAY_EXEC, NULL);
if (error)
diff --git a/fs/open.c b/fs/open.c
index 70e0230..7051000 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -27,6 +27,7 @@
#include <linux/pagemap.h>
#include <linux/syscalls.h>
#include <linux/rcupdate.h>
+#include <linux/audit.h>
#include <asm/unistd.h>
@@ -626,6 +627,8 @@
dentry = file->f_dentry;
inode = dentry->d_inode;
+ audit_inode(NULL, inode, 0);
+
err = -EROFS;
if (IS_RDONLY(inode))
goto out_putf;
@@ -775,7 +778,10 @@
file = fget(fd);
if (file) {
- error = chown_common(file->f_dentry, user, group);
+ struct dentry * dentry;
+ dentry = file->f_dentry;
+ audit_inode(NULL, dentry->d_inode, 0);
+ error = chown_common(dentry, user, group);
fput(file);
}
return error;
diff --git a/fs/xattr.c b/fs/xattr.c
index 80eca7d..e416190 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -17,6 +17,7 @@
#include <linux/syscalls.h>
#include <linux/module.h>
#include <linux/fsnotify.h>
+#include <linux/audit.h>
#include <asm/uaccess.h>
@@ -234,12 +235,15 @@
size_t size, int flags)
{
struct file *f;
+ struct dentry *dentry;
int error = -EBADF;
f = fget(fd);
if (!f)
return error;
- error = setxattr(f->f_dentry, name, value, size, flags);
+ dentry = f->f_dentry;
+ audit_inode(NULL, dentry->d_inode, 0);
+ error = setxattr(dentry, name, value, size, flags);
fput(f);
return error;
}
@@ -458,12 +462,15 @@
sys_fremovexattr(int fd, char __user *name)
{
struct file *f;
+ struct dentry *dentry;
int error = -EBADF;
f = fget(fd);
if (!f)
return error;
- error = removexattr(f->f_dentry, name);
+ dentry = f->f_dentry;
+ audit_inode(NULL, dentry->d_inode, 0);
+ error = removexattr(dentry, name);
fput(f);
return error;
}
diff --git a/include/linux/audit.h b/include/linux/audit.h
index fd65078..739b954 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -260,7 +260,20 @@
extern void audit_syscall_exit(struct task_struct *task, int failed, long return_code);
extern void audit_getname(const char *name);
extern void audit_putname(const char *name);
-extern void audit_inode(const char *name, const struct inode *inode, unsigned flags);
+extern void __audit_inode(const char *name, const struct inode *inode, unsigned flags);
+extern void __audit_inode_child(const char *dname, const struct inode *inode,
+ unsigned long pino);
+static inline void audit_inode(const char *name, const struct inode *inode,
+ unsigned flags) {
+ if (unlikely(current->audit_context))
+ __audit_inode(name, inode, flags);
+}
+static inline void audit_inode_child(const char *dname,
+ const struct inode *inode,
+ unsigned long pino) {
+ if (unlikely(current->audit_context))
+ __audit_inode_child(dname, inode, pino);
+}
/* Private API (for audit.c only) */
extern int audit_receive_filter(int type, int pid, int uid, int seq,
@@ -283,7 +296,10 @@
#define audit_syscall_exit(t,f,r) do { ; } while (0)
#define audit_getname(n) do { ; } while (0)
#define audit_putname(n) do { ; } while (0)
+#define __audit_inode(n,i,f) do { ; } while (0)
+#define __audit_inode_child(d,i,p) do { ; } while (0)
#define audit_inode(n,i,f) do { ; } while (0)
+#define audit_inode_child(d,i,p) do { ; } while (0)
#define audit_receive_filter(t,p,u,s,d,l) ({ -EOPNOTSUPP; })
#define auditsc_get_stamp(c,t,s) do { BUG(); } while (0)
#define audit_get_loginuid(c) ({ -1; })
diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h
index b5ff64d..94919c3 100644
--- a/include/linux/fsnotify.h
+++ b/include/linux/fsnotify.h
@@ -15,6 +15,7 @@
#include <linux/dnotify.h>
#include <linux/inotify.h>
+#include <linux/audit.h>
/*
* fsnotify_move - file old_name at old_dir was moved to new_name at new_dir
@@ -45,6 +46,8 @@
if (source) {
inotify_inode_queue_event(source, IN_MOVE_SELF, 0, NULL);
}
+ audit_inode_child(old_name, source, old_dir->i_ino);
+ audit_inode_child(new_name, target, new_dir->i_ino);
}
/*
@@ -74,6 +77,7 @@
{
inode_dir_notify(inode, DN_CREATE);
inotify_inode_queue_event(inode, IN_CREATE, 0, dentry->d_name.name);
+ audit_inode_child(dentry->d_name.name, dentry->d_inode, inode->i_ino);
}
/*
@@ -84,6 +88,7 @@
inode_dir_notify(inode, DN_CREATE);
inotify_inode_queue_event(inode, IN_CREATE | IN_ISDIR, 0,
dentry->d_name.name);
+ audit_inode_child(dentry->d_name.name, dentry->d_inode, inode->i_ino);
}
/*
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 55ba331..73f932b 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2,6 +2,7 @@
* Handles all system-call specific auditing features.
*
* Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
+ * Copyright 2005 Hewlett-Packard Development Company, L.P.
* Copyright (C) 2005 IBM Corporation
* All Rights Reserved.
*
@@ -31,11 +32,16 @@
* The support of additional filter rules compares (>, <, >=, <=) was
* added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005.
*
+ * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional
+ * filesystem information.
*/
#include <linux/init.h>
#include <asm/types.h>
#include <asm/atomic.h>
+#include <asm/types.h>
+#include <linux/fs.h>
+#include <linux/namei.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/mount.h>
@@ -97,12 +103,12 @@
struct audit_names {
const char *name;
unsigned long ino;
+ unsigned long pino;
dev_t dev;
umode_t mode;
uid_t uid;
gid_t gid;
dev_t rdev;
- unsigned flags;
};
struct audit_aux_data {
@@ -515,7 +521,8 @@
case AUDIT_INODE:
if (ctx) {
for (j = 0; j < ctx->name_count; j++) {
- if ( audit_comparator(ctx->names[j].ino, op, value)) {
+ if (audit_comparator(ctx->names[j].ino, op, value) ||
+ audit_comparator(ctx->names[j].pino, op, value)) {
++result;
break;
}
@@ -696,17 +703,17 @@
#if AUDIT_DEBUG == 2
if (context->auditable
||context->put_count + context->ino_count != context->name_count) {
- printk(KERN_ERR "audit.c:%d(:%d): major=%d in_syscall=%d"
+ printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
" name_count=%d put_count=%d"
" ino_count=%d [NOT freeing]\n",
- __LINE__,
+ __FILE__, __LINE__,
context->serial, context->major, context->in_syscall,
context->name_count, context->put_count,
context->ino_count);
for (i = 0; i < context->name_count; i++)
printk(KERN_ERR "names[%d] = %p = %s\n", i,
context->names[i].name,
- context->names[i].name);
+ context->names[i].name ?: "(null)");
dump_stack();
return;
}
@@ -932,27 +939,34 @@
}
}
for (i = 0; i < context->name_count; i++) {
+ unsigned long ino = context->names[i].ino;
+ unsigned long pino = context->names[i].pino;
+
ab = audit_log_start(context, gfp_mask, AUDIT_PATH);
if (!ab)
continue; /* audit_panic has been called */
audit_log_format(ab, "item=%d", i);
- if (context->names[i].name) {
- audit_log_format(ab, " name=");
+
+ audit_log_format(ab, " name=");
+ if (context->names[i].name)
audit_log_untrustedstring(ab, context->names[i].name);
- }
- audit_log_format(ab, " flags=%x\n", context->names[i].flags);
-
- if (context->names[i].ino != (unsigned long)-1)
- audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#o"
- " ouid=%u ogid=%u rdev=%02x:%02x",
- context->names[i].ino,
- MAJOR(context->names[i].dev),
- MINOR(context->names[i].dev),
- context->names[i].mode,
- context->names[i].uid,
- context->names[i].gid,
- MAJOR(context->names[i].rdev),
+ else
+ audit_log_format(ab, "(null)");
+
+ if (pino != (unsigned long)-1)
+ audit_log_format(ab, " parent=%lu", pino);
+ if (ino != (unsigned long)-1)
+ audit_log_format(ab, " inode=%lu", ino);
+ if ((pino != (unsigned long)-1) || (ino != (unsigned long)-1))
+ audit_log_format(ab, " dev=%02x:%02x mode=%#o"
+ " ouid=%u ogid=%u rdev=%02x:%02x",
+ MAJOR(context->names[i].dev),
+ MINOR(context->names[i].dev),
+ context->names[i].mode,
+ context->names[i].uid,
+ context->names[i].gid,
+ MAJOR(context->names[i].rdev),
MINOR(context->names[i].rdev));
audit_log_end(ab);
}
@@ -1174,7 +1188,7 @@
for (i = 0; i < context->name_count; i++)
printk(KERN_ERR "name[%d] = %p = %s\n", i,
context->names[i].name,
- context->names[i].name);
+ context->names[i].name ?: "(null)");
}
#endif
__putname(name);
@@ -1204,7 +1218,7 @@
*
* Called from fs/namei.c:path_lookup().
*/
-void audit_inode(const char *name, const struct inode *inode, unsigned flags)
+void __audit_inode(const char *name, const struct inode *inode, unsigned flags)
{
int idx;
struct audit_context *context = current->audit_context;
@@ -1230,13 +1244,93 @@
++context->ino_count;
#endif
}
- context->names[idx].flags = flags;
- context->names[idx].ino = inode->i_ino;
context->names[idx].dev = inode->i_sb->s_dev;
context->names[idx].mode = inode->i_mode;
context->names[idx].uid = inode->i_uid;
context->names[idx].gid = inode->i_gid;
context->names[idx].rdev = inode->i_rdev;
+ if ((flags & LOOKUP_PARENT) && (strcmp(name, "/") != 0) &&
+ (strcmp(name, ".") != 0)) {
+ context->names[idx].ino = (unsigned long)-1;
+ context->names[idx].pino = inode->i_ino;
+ } else {
+ context->names[idx].ino = inode->i_ino;
+ context->names[idx].pino = (unsigned long)-1;
+ }
+}
+
+/**
+ * audit_inode_child - collect inode info for created/removed objects
+ * @dname: inode's dentry name
+ * @inode: inode being audited
+ * @pino: inode number of dentry parent
+ *
+ * For syscalls that create or remove filesystem objects, audit_inode
+ * can only collect information for the filesystem object's parent.
+ * This call updates the audit context with the child's information.
+ * Syscalls that create a new filesystem object must be hooked after
+ * the object is created. Syscalls that remove a filesystem object
+ * must be hooked prior, in order to capture the target inode during
+ * unsuccessful attempts.
+ */
+void __audit_inode_child(const char *dname, const struct inode *inode,
+ unsigned long pino)
+{
+ int idx;
+ struct audit_context *context = current->audit_context;
+
+ if (!context->in_syscall)
+ return;
+
+ /* determine matching parent */
+ if (dname)
+ for (idx = 0; idx < context->name_count; idx++)
+ if (context->names[idx].pino == pino) {
+ const char *n;
+ const char *name = context->names[idx].name;
+ int dlen = strlen(dname);
+ int nlen = name ? strlen(name) : 0;
+
+ if (nlen < dlen)
+ continue;
+
+ /* disregard trailing slashes */
+ n = name + nlen - 1;
+ while ((*n == '/') && (n > name))
+ n--;
+
+ /* find last path component */
+ n = n - dlen + 1;
+ if (n < name)
+ continue;
+ else if (n > name) {
+ if (*--n != '/')
+ continue;
+ else
+ n++;
+ }
+
+ if (strncmp(n, dname, dlen) == 0)
+ goto update_context;
+ }
+
+ /* catch-all in case match not found */
+ idx = context->name_count++;
+ context->names[idx].name = NULL;
+ context->names[idx].pino = pino;
+#if AUDIT_DEBUG
+ context->ino_count++;
+#endif
+
+update_context:
+ if (inode) {
+ context->names[idx].ino = inode->i_ino;
+ context->names[idx].dev = inode->i_sb->s_dev;
+ context->names[idx].mode = inode->i_mode;
+ context->names[idx].uid = inode->i_uid;
+ context->names[idx].gid = inode->i_gid;
+ context->names[idx].rdev = inode->i_rdev;
+ }
}
/**
