| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1222463944.2872.217.camel@localhost.localdomain>
Date: Fri, 26 Sep 2008 17:19:04 -0400
From: Eric Paris <eparis@...hat.com>
To: linux-kernel@...r.kernel.org, malware-list@...ts.printk.net
Subject: [RFC 6/11] fanotify: add group priorities
fanotify: add group priorities
From: Eric Paris <eparis@...hat.com>
In preperation for blocking fanotify calls group priorities must be added.
async events will be sent as quickly as possible without waiting for a
response.
Signed-off-by: Eric Paris <eparis@...hat.com>
---
fs/notify/fanotify.h | 5 +++--
fs/notify/group.c | 36 +++++++++++++++++++++++++++++++-----
fs/notify/group_user.c | 14 ++++++++------
fs/notify/info_user.c | 2 +-
4 files changed, 43 insertions(+), 14 deletions(-)
diff --git a/fs/notify/fanotify.h b/fs/notify/fanotify.h
index 2a00668..12fb8d3 100644
--- a/fs/notify/fanotify.h
+++ b/fs/notify/fanotify.h
@@ -25,6 +25,7 @@ struct fanotify_group {
struct mutex fastpath_mutex; /* protect fastpath_entries list */
struct list_head fastpath_entries; /* all fastpath entries for this group */
+ unsigned int priority; /* order this group should receive msgs. low first */
char *name; /* group name used for register/unregister matching */
struct dentry *subdir; /* pointer to fanotify/name dentry */
struct dentry *notification; /* pointer to fanotify/name/notification dentry */
@@ -129,6 +130,6 @@ extern __init int fastpath_uninit(void);
extern void fanotify_get_group(struct fanotify_group *group);
extern void fanotify_put_group(struct fanotify_group *group);
-extern int fanotify_register_group(char *name, unsigned int mask);
-extern int fanotify_unregister_group(char *name, unsigned int mask);
+extern int fanotify_register_group(char *name, unsigned int priority, unsigned int mask);
+extern int fanotify_unregister_group(char *name, unsigned int priority, unsigned int mask);
#endif /* _LINUX_FANOTIFY_PRIVATE_H */
diff --git a/fs/notify/group.c b/fs/notify/group.c
index dc23127..81563ad 100644
--- a/fs/notify/group.c
+++ b/fs/notify/group.c
@@ -71,7 +71,7 @@ void fanotify_put_group(struct fanotify_group *group)
return;
}
-int fanotify_register_group(char *name, unsigned int mask)
+int fanotify_register_group(char *name, unsigned int priority, unsigned int mask)
{
struct dentry *subdir;
struct fanotify_group *group, *group_iter;
@@ -82,6 +82,10 @@ int fanotify_register_group(char *name, unsigned int mask)
if (!strcmp(name, group_iter->name)) {
mutex_unlock(&groups_mutex);
return -EEXIST;
+ } else if (group_iter->priority == priority) {
+ /* don't allow 2 groups with same priority */
+ mutex_unlock(&groups_mutex);
+ return -EINVAL;
}
}
@@ -96,6 +100,7 @@ int fanotify_register_group(char *name, unsigned int mask)
atomic_set(&group->num_clients, 0);
group->mask = mask;
+ group->priority = priority;
/* create sub-directory for this group. */
subdir = securityfs_create_dir(name, fanotify_fs_root);
@@ -118,8 +123,27 @@ int fanotify_register_group(char *name, unsigned int mask)
if (rc)
goto out_clean_info;
- /* add it */
- list_add_rcu(&group->group_list, &groups);
+ /* Do we need to be the first entry? */
+ if (list_empty(&groups)) {
+ list_add_rcu(&group->group_list, &groups);
+ mutex_unlock(&groups_mutex);
+ return 0;
+ }
+
+ list_for_each_entry(group_iter, &groups, group_list) {
+ /* insert in front of this one? */
+ if (priority < group_iter->priority) {
+ /* I used list_add_tail() to insert in front of group_iter... */
+ list_add_tail_rcu(&group->group_list, &group_iter->group_list);
+ break;
+ }
+
+ /* are we at the end? if so insert at end */
+ if (list_is_last(&group_iter->group_list, &groups)) {
+ list_add_tail_rcu(&group->group_list, &groups);
+ break;
+ }
+ }
mutex_unlock(&groups_mutex);
return 0;
@@ -138,14 +162,16 @@ out:
return rc;
}
-int fanotify_unregister_group(char *name, unsigned int mask)
+int fanotify_unregister_group(char *name, unsigned int priority, unsigned int mask)
{
int found = 0;
struct fanotify_group *group;
mutex_lock(&groups_mutex);
list_for_each_entry_rcu(group, &groups, group_list) {
- if (!strcmp(group->name, name) && (group->mask == mask)) {
+ if (!strcmp(group->name, name) &&
+ (group->mask == mask) &&
+ (group->priority == priority)) {
found = 1;
break;
}
diff --git a/fs/notify/group_user.c b/fs/notify/group_user.c
index 49ba712..a8663c1 100644
--- a/fs/notify/group_user.c
+++ b/fs/notify/group_user.c
@@ -45,6 +45,7 @@ static ssize_t fanotify_register_write(struct file *file, const char __user *buf
char *p;
char *group_name;
unsigned int mask;
+ unsigned int priority;
int rc = 0;
p = simple_transaction_get(file, buf, lenp);
@@ -57,15 +58,15 @@ static ssize_t fanotify_register_write(struct file *file, const char __user *buf
goto out;
}
- rc = sscanf(p, "%s %x\n", group_name, &mask);
- if (rc != 2) {
+ rc = sscanf(p, "%s %u %x\n", group_name, &priority, &mask);
+ if (rc != 3) {
if (rc >= 0)
rc = -EPROTO;
goto out;
}
// FIXME do mask validation
- rc = fanotify_register_group(group_name, mask);
+ rc = fanotify_register_group(group_name, priority, mask);
if (rc)
goto out;
@@ -81,6 +82,7 @@ static ssize_t fanotify_unregister_write(struct file *file, const char __user *b
char *p;
char *group_name;
unsigned int mask;
+ unsigned int priority;
int rc = 0;
group_name = kzalloc(lenp, GFP_KERNEL);
@@ -93,14 +95,14 @@ static ssize_t fanotify_unregister_write(struct file *file, const char __user *b
goto out;
}
- rc = sscanf(p, "%s %x\n", group_name, &mask);
- if (rc != 2) {
+ rc = sscanf(p, "%s %u %x\n", group_name, &priority, &mask);
+ if (rc != 3) {
if (rc >= 0)
rc = -EPROTO;
goto out;
}
- rc = fanotify_unregister_group(group_name, mask);
+ rc = fanotify_unregister_group(group_name, priority, mask);
if (rc)
goto out;
diff --git a/fs/notify/info_user.c b/fs/notify/info_user.c
index 21a4465..6402e2d 100644
--- a/fs/notify/info_user.c
+++ b/fs/notify/info_user.c
@@ -48,7 +48,7 @@ static ssize_t fanotify_info_read(struct file *file, char __user *buf, size_t le
return -ENOMEM;
/* Build metadata string to send to the listener */
- len = snprintf(output, PAGE_SIZE, "%s %x\n", group->name, group->mask);
+ len = snprintf(output, PAGE_SIZE, "%s %u %x\n", group->name, group->priority, group->mask);
if (len < 0)
goto out;
len = simple_read_from_buffer(buf, lenp, offset, output, len);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists