3:44 p.m.
Make more effort to detect previously collected names, so we don't log
multiple PATH records for a single filesystem object. Add
audit_inc_name_count() to reduce duplicate code.
Signed-off-by: Amy Griffis <amy.griffis(a)hp.com>
---
kernel/auditsc.c | 143 +++++++++++++++++++++++++++++++----------------------
1 files changed, 84 insertions(+), 59 deletions(-)
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index e241541..3cfa38f 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -78,11 +78,6 @@ extern int audit_enabled;
* for saving names from getname(). */
#define AUDIT_NAMES 20
-/* AUDIT_NAMES_RESERVED is the number of slots we reserve in the
- * audit_context from being used for nameless inodes from
- * path_lookup. */
-#define AUDIT_NAMES_RESERVED 7
-
/* Indicates that audit should log the full pathname. */
#define AUDIT_NAME_FULL -1
@@ -1280,6 +1275,28 @@ void audit_putname(const char *name)
#endif
}
+static int audit_inc_name_count(struct audit_context *context,
+ const struct inode *inode)
+{
+ if (context->name_count >= AUDIT_NAMES) {
+ if (inode)
+ printk(KERN_DEBUG "name_count maxed, losing inode data: "
+ "dev=%02x:%02x, inode=%lu",
+ MAJOR(inode->i_sb->s_dev),
+ MINOR(inode->i_sb->s_dev),
+ inode->i_ino);
+
+ else
+ printk(KERN_DEBUG "name_count maxed, losing inode data");
+ return 1;
+ }
+ context->name_count++;
+#if AUDIT_DEBUG
+ context->ino_count++;
+#endif
+ return 0;
+}
+
/* Copy inode data into an audit_names. */
static void audit_copy_inode(struct audit_names *name, const struct inode *inode)
{
@@ -1317,13 +1334,10 @@ void __audit_inode(const char *name, const struct inode *inode)
else {
/* FIXME: how much do we care about inodes that have no
* associated name? */
- if (context->name_count >= AUDIT_NAMES - AUDIT_NAMES_RESERVED)
+ if (audit_inc_name_count(context, inode))
return;
- idx = context->name_count++;
+ idx = context->name_count - 1;
context->names[idx].name = NULL;
-#if AUDIT_DEBUG
- ++context->ino_count;
-#endif
}
audit_copy_inode(&context->names[idx], inode);
}
@@ -1347,69 +1361,80 @@ void __audit_inode_child(const char *dname, const struct inode
*inode,
{
int idx;
struct audit_context *context = current->audit_context;
- const char *found_name = NULL;
+ const char *found_parent = NULL, *found_child = NULL;
int dirlen = 0;
if (!context->in_syscall)
return;
- /* determine matching parent */
if (!dname)
- goto update_context;
- for (idx = 0; idx < context->name_count; idx++)
- if (context->names[idx].ino == parent->i_ino) {
- const char *name = context->names[idx].name;
+ goto add_names;
- if (!name)
- continue;
+ /* parent is more likely, look for it first */
+ for (idx = 0; idx < context->name_count; idx++) {
+ struct audit_names *n = &context->names[idx];
- if (audit_compare_dname_path(dname, name, &dirlen) == 0) {
- context->names[idx].name_len = dirlen;
- found_name = name;
- break;
- }
+ if (!n->name)
+ continue;
+
+ if ((n->ino == parent->i_ino) &&
+ !audit_compare_dname_path(dname, n->name, &dirlen)) {
+ n->name_len = dirlen; /* update parent data in place */
+ found_parent = n->name;
+ goto add_names;
}
+ }
-update_context:
- idx = context->name_count;
- if (context->name_count == AUDIT_NAMES) {
- printk(KERN_DEBUG "name_count maxed and losing %s\n",
- found_name ?: "(null)");
- return;
+ /* no matching parent, look for matching child */
+ for (idx = 0; idx < context->name_count; idx++) {
+ struct audit_names *n = &context->names[idx];
+
+ if (!n->name)
+ continue;
+
+ /* strcmp() is the more likely scenario */
+ if (!strcmp(dname, n->name) ||
+ !audit_compare_dname_path(dname, n->name, &dirlen)) {
+ if (inode)
+ audit_copy_inode(n, inode);
+ else
+ n->ino = (unsigned long)-1;
+ found_child = n->name;
+ goto add_names;
+ }
}
- context->name_count++;
-#if AUDIT_DEBUG
- context->ino_count++;
-#endif
- /* Re-use the name belonging to the slot for a matching parent directory.
- * All names for this context are relinquished in audit_free_names() */
- context->names[idx].name = found_name;
- context->names[idx].name_len = AUDIT_NAME_FULL;
- context->names[idx].name_put = 0; /* don't call __putname() */
-
- if (!inode)
- context->names[idx].ino = (unsigned long)-1;
- else
- audit_copy_inode(&context->names[idx], inode);
-
- /* A parent was not found in audit_names, so copy the inode data for the
- * provided parent. */
- if (!found_name) {
- idx = context->name_count;
- if (context->name_count == AUDIT_NAMES) {
- printk(KERN_DEBUG
- "name_count maxed and losing parent inode data: dev=%02x:%02x, inode=%lu",
- MAJOR(parent->i_sb->s_dev),
- MINOR(parent->i_sb->s_dev),
- parent->i_ino);
+
+add_names:
+ if (!found_parent) {
+ if (audit_inc_name_count(context, parent))
return;
- }
- context->name_count++;
-#if AUDIT_DEBUG
- context->ino_count++;
-#endif
+ idx = context->name_count - 1;
+ context->names[idx].name = NULL;
audit_copy_inode(&context->names[idx], parent);
}
+
+ if (!found_child) {
+ if (audit_inc_name_count(context, inode))
+ return;
+ idx = context->name_count - 1;
+
+ /* Re-use the name belonging to the slot for a matching parent
+ * directory. All names for this context are relinquished in
+ * audit_free_names() */
+ if (found_parent) {
+ context->names[idx].name = found_parent;
+ context->names[idx].name_len = AUDIT_NAME_FULL;
+ /* don't call __putname() */
+ context->names[idx].name_put = 0;
+ } else {
+ context->names[idx].name = NULL;
+ }
+
+ if (inode)
+ audit_copy_inode(&context->names[idx], inode);
+ else
+ context->names[idx].ino = (unsigned long)-1;
+ }
}
/**
--
1.4.4.4