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-rw-r--r--fs/notify/fanotify/Kconfig2
-rw-r--r--fs/notify/fanotify/fanotify.c258
-rw-r--r--fs/notify/fanotify/fanotify.h50
-rw-r--r--fs/notify/fanotify/fanotify_user.c498
4 files changed, 459 insertions, 349 deletions
diff --git a/fs/notify/fanotify/Kconfig b/fs/notify/fanotify/Kconfig
index 7dceff005a6..e5f911bd80d 100644
--- a/fs/notify/fanotify/Kconfig
+++ b/fs/notify/fanotify/Kconfig
@@ -4,7 +4,7 @@ config FANOTIFY
select ANON_INODES
default n
---help---
- Say Y here to enable fanotify suport. fanotify is a file access
+ Say Y here to enable fanotify support. fanotify is a file access
notification system which differs from inotify in that it sends
an open file descriptor to the userspace listener along with
the event.
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index f35794b97e8..ee9cb3795c2 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -9,84 +9,59 @@
#include <linux/types.h>
#include <linux/wait.h>
-static bool should_merge(struct fsnotify_event *old, struct fsnotify_event *new)
+#include "fanotify.h"
+
+static bool should_merge(struct fsnotify_event *old_fsn,
+ struct fsnotify_event *new_fsn)
{
- pr_debug("%s: old=%p new=%p\n", __func__, old, new);
-
- if (old->to_tell == new->to_tell &&
- old->data_type == new->data_type &&
- old->tgid == new->tgid) {
- switch (old->data_type) {
- case (FSNOTIFY_EVENT_PATH):
- if ((old->path.mnt == new->path.mnt) &&
- (old->path.dentry == new->path.dentry))
- return true;
- case (FSNOTIFY_EVENT_NONE):
- return true;
- default:
- BUG();
- };
- }
+ struct fanotify_event_info *old, *new;
+
+ pr_debug("%s: old=%p new=%p\n", __func__, old_fsn, new_fsn);
+ old = FANOTIFY_E(old_fsn);
+ new = FANOTIFY_E(new_fsn);
+
+ if (old_fsn->inode == new_fsn->inode && old->tgid == new->tgid &&
+ old->path.mnt == new->path.mnt &&
+ old->path.dentry == new->path.dentry)
+ return true;
return false;
}
/* and the list better be locked by something too! */
-static struct fsnotify_event *fanotify_merge(struct list_head *list,
- struct fsnotify_event *event)
+static int fanotify_merge(struct list_head *list, struct fsnotify_event *event)
{
- struct fsnotify_event_holder *test_holder;
- struct fsnotify_event *test_event = NULL;
- struct fsnotify_event *new_event;
+ struct fsnotify_event *test_event;
+ bool do_merge = false;
pr_debug("%s: list=%p event=%p\n", __func__, list, event);
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+ /*
+ * Don't merge a permission event with any other event so that we know
+ * the event structure we have created in fanotify_handle_event() is the
+ * one we should check for permission response.
+ */
+ if (event->mask & FAN_ALL_PERM_EVENTS)
+ return 0;
+#endif
- list_for_each_entry_reverse(test_holder, list, event_list) {
- if (should_merge(test_holder->event, event)) {
- test_event = test_holder->event;
+ list_for_each_entry_reverse(test_event, list, list) {
+ if (should_merge(test_event, event)) {
+ do_merge = true;
break;
}
}
- if (!test_event)
- return NULL;
-
- fsnotify_get_event(test_event);
-
- /* if they are exactly the same we are done */
- if (test_event->mask == event->mask)
- return test_event;
-
- /*
- * if the refcnt == 2 this is the only queue
- * for this event and so we can update the mask
- * in place.
- */
- if (atomic_read(&test_event->refcnt) == 2) {
- test_event->mask |= event->mask;
- return test_event;
- }
-
- new_event = fsnotify_clone_event(test_event);
-
- /* done with test_event */
- fsnotify_put_event(test_event);
-
- /* couldn't allocate memory, merge was not possible */
- if (unlikely(!new_event))
- return ERR_PTR(-ENOMEM);
-
- /* build new event and replace it on the list */
- new_event->mask = (test_event->mask | event->mask);
- fsnotify_replace_event(test_holder, new_event);
+ if (!do_merge)
+ return 0;
- /* we hold a reference on new_event from clone_event */
- return new_event;
+ test_event->mask |= event->mask;
+ return 1;
}
#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
-static int fanotify_get_response_from_access(struct fsnotify_group *group,
- struct fsnotify_event *event)
+static int fanotify_get_response(struct fsnotify_group *group,
+ struct fanotify_perm_event_info *event)
{
int ret;
@@ -99,7 +74,6 @@ static int fanotify_get_response_from_access(struct fsnotify_group *group,
return 0;
/* userspace responded, convert to something usable */
- spin_lock(&event->lock);
switch (event->response) {
case FAN_ALLOW:
ret = 0;
@@ -109,7 +83,6 @@ static int fanotify_get_response_from_access(struct fsnotify_group *group,
ret = -EPERM;
}
event->response = 0;
- spin_unlock(&event->lock);
pr_debug("%s: group=%p event=%p about to return ret=%d\n", __func__,
group, event, ret);
@@ -118,58 +91,17 @@ static int fanotify_get_response_from_access(struct fsnotify_group *group,
}
#endif
-static int fanotify_handle_event(struct fsnotify_group *group,
- struct fsnotify_mark *inode_mark,
- struct fsnotify_mark *fanotify_mark,
- struct fsnotify_event *event)
-{
- int ret = 0;
- struct fsnotify_event *notify_event = NULL;
-
- BUILD_BUG_ON(FAN_ACCESS != FS_ACCESS);
- BUILD_BUG_ON(FAN_MODIFY != FS_MODIFY);
- BUILD_BUG_ON(FAN_CLOSE_NOWRITE != FS_CLOSE_NOWRITE);
- BUILD_BUG_ON(FAN_CLOSE_WRITE != FS_CLOSE_WRITE);
- BUILD_BUG_ON(FAN_OPEN != FS_OPEN);
- BUILD_BUG_ON(FAN_EVENT_ON_CHILD != FS_EVENT_ON_CHILD);
- BUILD_BUG_ON(FAN_Q_OVERFLOW != FS_Q_OVERFLOW);
- BUILD_BUG_ON(FAN_OPEN_PERM != FS_OPEN_PERM);
- BUILD_BUG_ON(FAN_ACCESS_PERM != FS_ACCESS_PERM);
- BUILD_BUG_ON(FAN_ONDIR != FS_ISDIR);
-
- pr_debug("%s: group=%p event=%p\n", __func__, group, event);
-
- notify_event = fsnotify_add_notify_event(group, event, NULL, fanotify_merge);
- if (IS_ERR(notify_event))
- return PTR_ERR(notify_event);
-
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
- if (event->mask & FAN_ALL_PERM_EVENTS) {
- /* if we merged we need to wait on the new event */
- if (notify_event)
- event = notify_event;
- ret = fanotify_get_response_from_access(group, event);
- }
-#endif
-
- if (notify_event)
- fsnotify_put_event(notify_event);
-
- return ret;
-}
-
-static bool fanotify_should_send_event(struct fsnotify_group *group,
- struct inode *to_tell,
- struct fsnotify_mark *inode_mark,
+static bool fanotify_should_send_event(struct fsnotify_mark *inode_mark,
struct fsnotify_mark *vfsmnt_mark,
- __u32 event_mask, void *data, int data_type)
+ u32 event_mask,
+ void *data, int data_type)
{
__u32 marks_mask, marks_ignored_mask;
struct path *path = data;
- pr_debug("%s: group=%p to_tell=%p inode_mark=%p vfsmnt_mark=%p "
- "mask=%x data=%p data_type=%d\n", __func__, group, to_tell,
- inode_mark, vfsmnt_mark, event_mask, data, data_type);
+ pr_debug("%s: inode_mark=%p vfsmnt_mark=%p mask=%x data=%p"
+ " data_type=%d\n", __func__, inode_mark, vfsmnt_mark,
+ event_mask, data, data_type);
/* if we don't have enough info to send an event to userspace say no */
if (data_type != FSNOTIFY_EVENT_PATH)
@@ -210,6 +142,93 @@ static bool fanotify_should_send_event(struct fsnotify_group *group,
return false;
}
+struct fanotify_event_info *fanotify_alloc_event(struct inode *inode, u32 mask,
+ struct path *path)
+{
+ struct fanotify_event_info *event;
+
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+ if (mask & FAN_ALL_PERM_EVENTS) {
+ struct fanotify_perm_event_info *pevent;
+
+ pevent = kmem_cache_alloc(fanotify_perm_event_cachep,
+ GFP_KERNEL);
+ if (!pevent)
+ return NULL;
+ event = &pevent->fae;
+ pevent->response = 0;
+ goto init;
+ }
+#endif
+ event = kmem_cache_alloc(fanotify_event_cachep, GFP_KERNEL);
+ if (!event)
+ return NULL;
+init: __maybe_unused
+ fsnotify_init_event(&event->fse, inode, mask);
+ event->tgid = get_pid(task_tgid(current));
+ if (path) {
+ event->path = *path;
+ path_get(&event->path);
+ } else {
+ event->path.mnt = NULL;
+ event->path.dentry = NULL;
+ }
+ return event;
+}
+
+static int fanotify_handle_event(struct fsnotify_group *group,
+ struct inode *inode,
+ struct fsnotify_mark *inode_mark,
+ struct fsnotify_mark *fanotify_mark,
+ u32 mask, void *data, int data_type,
+ const unsigned char *file_name, u32 cookie)
+{
+ int ret = 0;
+ struct fanotify_event_info *event;
+ struct fsnotify_event *fsn_event;
+
+ BUILD_BUG_ON(FAN_ACCESS != FS_ACCESS);
+ BUILD_BUG_ON(FAN_MODIFY != FS_MODIFY);
+ BUILD_BUG_ON(FAN_CLOSE_NOWRITE != FS_CLOSE_NOWRITE);
+ BUILD_BUG_ON(FAN_CLOSE_WRITE != FS_CLOSE_WRITE);
+ BUILD_BUG_ON(FAN_OPEN != FS_OPEN);
+ BUILD_BUG_ON(FAN_EVENT_ON_CHILD != FS_EVENT_ON_CHILD);
+ BUILD_BUG_ON(FAN_Q_OVERFLOW != FS_Q_OVERFLOW);
+ BUILD_BUG_ON(FAN_OPEN_PERM != FS_OPEN_PERM);
+ BUILD_BUG_ON(FAN_ACCESS_PERM != FS_ACCESS_PERM);
+ BUILD_BUG_ON(FAN_ONDIR != FS_ISDIR);
+
+ if (!fanotify_should_send_event(inode_mark, fanotify_mark, mask, data,
+ data_type))
+ return 0;
+
+ pr_debug("%s: group=%p inode=%p mask=%x\n", __func__, group, inode,
+ mask);
+
+ event = fanotify_alloc_event(inode, mask, data);
+ if (unlikely(!event))
+ return -ENOMEM;
+
+ fsn_event = &event->fse;
+ ret = fsnotify_add_notify_event(group, fsn_event, fanotify_merge);
+ if (ret) {
+ /* Permission events shouldn't be merged */
+ BUG_ON(ret == 1 && mask & FAN_ALL_PERM_EVENTS);
+ /* Our event wasn't used in the end. Free it. */
+ fsnotify_destroy_event(group, fsn_event);
+
+ return 0;
+ }
+
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+ if (mask & FAN_ALL_PERM_EVENTS) {
+ ret = fanotify_get_response(group, FANOTIFY_PE(fsn_event));
+ fsnotify_destroy_event(group, fsn_event);
+ }
+#endif
+ return ret;
+}
+
static void fanotify_free_group_priv(struct fsnotify_group *group)
{
struct user_struct *user;
@@ -219,10 +238,25 @@ static void fanotify_free_group_priv(struct fsnotify_group *group)
free_uid(user);
}
+static void fanotify_free_event(struct fsnotify_event *fsn_event)
+{
+ struct fanotify_event_info *event;
+
+ event = FANOTIFY_E(fsn_event);
+ path_put(&event->path);
+ put_pid(event->tgid);
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+ if (fsn_event->mask & FAN_ALL_PERM_EVENTS) {
+ kmem_cache_free(fanotify_perm_event_cachep,
+ FANOTIFY_PE(fsn_event));
+ return;
+ }
+#endif
+ kmem_cache_free(fanotify_event_cachep, event);
+}
+
const struct fsnotify_ops fanotify_fsnotify_ops = {
.handle_event = fanotify_handle_event,
- .should_send_event = fanotify_should_send_event,
.free_group_priv = fanotify_free_group_priv,
- .free_event_priv = NULL,
- .freeing_mark = NULL,
+ .free_event = fanotify_free_event,
};
diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
new file mode 100644
index 00000000000..2a5fb14115d
--- /dev/null
+++ b/fs/notify/fanotify/fanotify.h
@@ -0,0 +1,50 @@
+#include <linux/fsnotify_backend.h>
+#include <linux/path.h>
+#include <linux/slab.h>
+
+extern struct kmem_cache *fanotify_event_cachep;
+extern struct kmem_cache *fanotify_perm_event_cachep;
+
+/*
+ * Structure for normal fanotify events. It gets allocated in
+ * fanotify_handle_event() and freed when the information is retrieved by
+ * userspace
+ */
+struct fanotify_event_info {
+ struct fsnotify_event fse;
+ /*
+ * We hold ref to this path so it may be dereferenced at any point
+ * during this object's lifetime
+ */
+ struct path path;
+ struct pid *tgid;
+};
+
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+/*
+ * Structure for permission fanotify events. It gets allocated and freed in
+ * fanotify_handle_event() since we wait there for user response. When the
+ * information is retrieved by userspace the structure is moved from
+ * group->notification_list to group->fanotify_data.access_list to wait for
+ * user response.
+ */
+struct fanotify_perm_event_info {
+ struct fanotify_event_info fae;
+ int response; /* userspace answer to question */
+ int fd; /* fd we passed to userspace for this event */
+};
+
+static inline struct fanotify_perm_event_info *
+FANOTIFY_PE(struct fsnotify_event *fse)
+{
+ return container_of(fse, struct fanotify_perm_event_info, fae.fse);
+}
+#endif
+
+static inline struct fanotify_event_info *FANOTIFY_E(struct fsnotify_event *fse)
+{
+ return container_of(fse, struct fanotify_event_info, fse);
+}
+
+struct fanotify_event_info *fanotify_alloc_event(struct inode *inode, u32 mask,
+ struct path *path);
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 3568c8a8b13..3fdc8a3e113 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -13,25 +13,36 @@
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/uaccess.h>
+#include <linux/compat.h>
#include <asm/ioctls.h>
#include "../../mount.h"
+#include "../fdinfo.h"
+#include "fanotify.h"
#define FANOTIFY_DEFAULT_MAX_EVENTS 16384
#define FANOTIFY_DEFAULT_MAX_MARKS 8192
#define FANOTIFY_DEFAULT_MAX_LISTENERS 128
+/*
+ * All flags that may be specified in parameter event_f_flags of fanotify_init.
+ *
+ * Internal and external open flags are stored together in field f_flags of
+ * struct file. Only external open flags shall be allowed in event_f_flags.
+ * Internal flags like FMODE_NONOTIFY, FMODE_EXEC, FMODE_NOCMTIME shall be
+ * excluded.
+ */
+#define FANOTIFY_INIT_ALL_EVENT_F_BITS ( \
+ O_ACCMODE | O_APPEND | O_NONBLOCK | \
+ __O_SYNC | O_DSYNC | O_CLOEXEC | \
+ O_LARGEFILE | O_NOATIME )
+
extern const struct fsnotify_ops fanotify_fsnotify_ops;
static struct kmem_cache *fanotify_mark_cache __read_mostly;
-static struct kmem_cache *fanotify_response_event_cache __read_mostly;
-
-struct fanotify_response_event {
- struct list_head list;
- __s32 fd;
- struct fsnotify_event *event;
-};
+struct kmem_cache *fanotify_event_cachep __read_mostly;
+struct kmem_cache *fanotify_perm_event_cachep __read_mostly;
/*
* Get an fsnotify notification event if one exists and is small
@@ -58,11 +69,11 @@ static struct fsnotify_event *get_one_event(struct fsnotify_group *group,
return fsnotify_remove_notify_event(group);
}
-static int create_fd(struct fsnotify_group *group, struct fsnotify_event *event)
+static int create_fd(struct fsnotify_group *group,
+ struct fanotify_event_info *event,
+ struct file **file)
{
int client_fd;
- struct dentry *dentry;
- struct vfsmount *mnt;
struct file *new_file;
pr_debug("%s: group=%p event=%p\n", __func__, group, event);
@@ -71,22 +82,14 @@ static int create_fd(struct fsnotify_group *group, struct fsnotify_event *event)
if (client_fd < 0)
return client_fd;
- if (event->data_type != FSNOTIFY_EVENT_PATH) {
- WARN_ON(1);
- put_unused_fd(client_fd);
- return -EINVAL;
- }
-
/*
* we need a new file handle for the userspace program so it can read even if it was
* originally opened O_WRONLY.
*/
- dentry = dget(event->path.dentry);
- mnt = mntget(event->path.mnt);
/* it's possible this event was an overflow event. in that case dentry and mnt
* are NULL; That's fine, just don't call dentry open */
- if (dentry && mnt)
- new_file = dentry_open(dentry, mnt,
+ if (event->path.dentry && event->path.mnt)
+ new_file = dentry_open(&event->path,
group->fanotify_data.f_flags | FMODE_NONOTIFY,
current_cred());
else
@@ -102,30 +105,35 @@ static int create_fd(struct fsnotify_group *group, struct fsnotify_event *event)
put_unused_fd(client_fd);
client_fd = PTR_ERR(new_file);
} else {
- fd_install(client_fd, new_file);
+ *file = new_file;
}
return client_fd;
}
static int fill_event_metadata(struct fsnotify_group *group,
- struct fanotify_event_metadata *metadata,
- struct fsnotify_event *event)
+ struct fanotify_event_metadata *metadata,
+ struct fsnotify_event *fsn_event,
+ struct file **file)
{
int ret = 0;
+ struct fanotify_event_info *event;
pr_debug("%s: group=%p metadata=%p event=%p\n", __func__,
- group, metadata, event);
+ group, metadata, fsn_event);
+ *file = NULL;
+ event = container_of(fsn_event, struct fanotify_event_info, fse);
metadata->event_len = FAN_EVENT_METADATA_LEN;
metadata->metadata_len = FAN_EVENT_METADATA_LEN;
metadata->vers = FANOTIFY_METADATA_VERSION;
- metadata->mask = event->mask & FAN_ALL_OUTGOING_EVENTS;
+ metadata->reserved = 0;
+ metadata->mask = fsn_event->mask & FAN_ALL_OUTGOING_EVENTS;
metadata->pid = pid_vnr(event->tgid);
- if (unlikely(event->mask & FAN_Q_OVERFLOW))
+ if (unlikely(fsn_event->mask & FAN_Q_OVERFLOW))
metadata->fd = FAN_NOFD;
else {
- metadata->fd = create_fd(group, event);
+ metadata->fd = create_fd(group, event, file);
if (metadata->fd < 0)
ret = metadata->fd;
}
@@ -134,33 +142,34 @@ static int fill_event_metadata(struct fsnotify_group *group,
}
#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
-static struct fanotify_response_event *dequeue_re(struct fsnotify_group *group,
- __s32 fd)
+static struct fanotify_perm_event_info *dequeue_event(
+ struct fsnotify_group *group, int fd)
{
- struct fanotify_response_event *re, *return_re = NULL;
+ struct fanotify_perm_event_info *event, *return_e = NULL;
- mutex_lock(&group->fanotify_data.access_mutex);
- list_for_each_entry(re, &group->fanotify_data.access_list, list) {
- if (re->fd != fd)
+ spin_lock(&group->fanotify_data.access_lock);
+ list_for_each_entry(event, &group->fanotify_data.access_list,
+ fae.fse.list) {
+ if (event->fd != fd)
continue;
- list_del_init(&re->list);
- return_re = re;
+ list_del_init(&event->fae.fse.list);
+ return_e = event;
break;
}
- mutex_unlock(&group->fanotify_data.access_mutex);
+ spin_unlock(&group->fanotify_data.access_lock);
- pr_debug("%s: found return_re=%p\n", __func__, return_re);
+ pr_debug("%s: found return_re=%p\n", __func__, return_e);
- return return_re;
+ return return_e;
}
static int process_access_response(struct fsnotify_group *group,
struct fanotify_response *response_struct)
{
- struct fanotify_response_event *re;
- __s32 fd = response_struct->fd;
- __u32 response = response_struct->response;
+ struct fanotify_perm_event_info *event;
+ int fd = response_struct->fd;
+ int response = response_struct->response;
pr_debug("%s: group=%p fd=%d response=%d\n", __func__, group,
fd, response);
@@ -180,83 +189,15 @@ static int process_access_response(struct fsnotify_group *group,
if (fd < 0)
return -EINVAL;
- re = dequeue_re(group, fd);
- if (!re)
+ event = dequeue_event(group, fd);
+ if (!event)
return -ENOENT;
- re->event->response = response;
-
+ event->response = response;
wake_up(&group->fanotify_data.access_waitq);
- kmem_cache_free(fanotify_response_event_cache, re);
-
return 0;
}
-
-static int prepare_for_access_response(struct fsnotify_group *group,
- struct fsnotify_event *event,
- __s32 fd)
-{
- struct fanotify_response_event *re;
-
- if (!(event->mask & FAN_ALL_PERM_EVENTS))
- return 0;
-
- re = kmem_cache_alloc(fanotify_response_event_cache, GFP_KERNEL);
- if (!re)
- return -ENOMEM;
-
- re->event = event;
- re->fd = fd;
-
- mutex_lock(&group->fanotify_data.access_mutex);
-
- if (atomic_read(&group->fanotify_data.bypass_perm)) {
- mutex_unlock(&group->fanotify_data.access_mutex);
- kmem_cache_free(fanotify_response_event_cache, re);
- event->response = FAN_ALLOW;
- return 0;
- }
-
- list_add_tail(&re->list, &group->fanotify_data.access_list);
- mutex_unlock(&group->fanotify_data.access_mutex);
-
- return 0;
-}
-
-static void remove_access_response(struct fsnotify_group *group,
- struct fsnotify_event *event,
- __s32 fd)
-{
- struct fanotify_response_event *re;
-
- if (!(event->mask & FAN_ALL_PERM_EVENTS))
- return;
-
- re = dequeue_re(group, fd);
- if (!re)
- return;
-
- BUG_ON(re->event != event);
-
- kmem_cache_free(fanotify_response_event_cache, re);
-
- return;
-}
-#else
-static int prepare_for_access_response(struct fsnotify_group *group,
- struct fsnotify_event *event,
- __s32 fd)
-{
- return 0;
-}
-
-static void remove_access_response(struct fsnotify_group *group,
- struct fsnotify_event *event,
- __s32 fd)
-{
- return;
-}
#endif
static ssize_t copy_event_to_user(struct fsnotify_group *group,
@@ -264,38 +205,35 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group,
char __user *buf)
{
struct fanotify_event_metadata fanotify_event_metadata;
+ struct file *f;
int fd, ret;
pr_debug("%s: group=%p event=%p\n", __func__, group, event);
- ret = fill_event_metadata(group, &fanotify_event_metadata, event);
+ ret = fill_event_metadata(group, &fanotify_event_metadata, event, &f);
if (ret < 0)
- goto out;
+ return ret;
fd = fanotify_event_metadata.fd;
- ret = prepare_for_access_response(group, event, fd);
- if (ret)
- goto out_close_fd;
-
ret = -EFAULT;
if (copy_to_user(buf, &fanotify_event_metadata,
fanotify_event_metadata.event_len))
- goto out_kill_access_response;
+ goto out_close_fd;
+
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+ if (event->mask & FAN_ALL_PERM_EVENTS)
+ FANOTIFY_PE(event)->fd = fd;
+#endif
+ if (fd != FAN_NOFD)
+ fd_install(fd, f);
return fanotify_event_metadata.event_len;
-out_kill_access_response:
- remove_access_response(group, event, fd);
out_close_fd:
- if (fd != FAN_NOFD)
- sys_close(fd);
-out:
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
- if (event->mask & FAN_ALL_PERM_EVENTS) {
- event->response = FAN_DENY;
- wake_up(&group->fanotify_data.access_waitq);
+ if (fd != FAN_NOFD) {
+ put_unused_fd(fd);
+ fput(f);
}
-#endif
return ret;
}
@@ -335,30 +273,50 @@ static ssize_t fanotify_read(struct file *file, char __user *buf,
kevent = get_one_event(group, count);
mutex_unlock(&group->notification_mutex);
- if (kevent) {
+ if (IS_ERR(kevent)) {
ret = PTR_ERR(kevent);
- if (IS_ERR(kevent))
+ break;
+ }
+
+ if (!kevent) {
+ ret = -EAGAIN;
+ if (file->f_flags & O_NONBLOCK)
break;
- ret = copy_event_to_user(group, kevent, buf);
- fsnotify_put_event(kevent);
- if (ret < 0)
+
+ ret = -ERESTARTSYS;
+ if (signal_pending(current))
+ break;
+
+ if (start != buf)
break;
- buf += ret;
- count -= ret;
+ schedule();
continue;
}
- ret = -EAGAIN;
- if (file->f_flags & O_NONBLOCK)
- break;
- ret = -ERESTARTSYS;
- if (signal_pending(current))
- break;
-
- if (start != buf)
- break;
-
- schedule();
+ ret = copy_event_to_user(group, kevent, buf);
+ /*
+ * Permission events get queued to wait for response. Other
+ * events can be destroyed now.
+ */
+ if (!(kevent->mask & FAN_ALL_PERM_EVENTS)) {
+ fsnotify_destroy_event(group, kevent);
+ if (ret < 0)
+ break;
+ } else {
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+ if (ret < 0) {
+ FANOTIFY_PE(kevent)->response = FAN_DENY;
+ wake_up(&group->fanotify_data.access_waitq);
+ break;
+ }
+ spin_lock(&group->fanotify_data.access_lock);
+ list_add_tail(&kevent->list,
+ &group->fanotify_data.access_list);
+ spin_unlock(&group->fanotify_data.access_lock);
+#endif
+ }
+ buf += ret;
+ count -= ret;
}
finish_wait(&group->notification_waitq, &wait);
@@ -399,27 +357,27 @@ static int fanotify_release(struct inode *ignored, struct file *file)
struct fsnotify_group *group = file->private_data;
#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
- struct fanotify_response_event *re, *lre;
+ struct fanotify_perm_event_info *event, *next;
- mutex_lock(&group->fanotify_data.access_mutex);
+ spin_lock(&group->fanotify_data.access_lock);
atomic_inc(&group->fanotify_data.bypass_perm);
- list_for_each_entry_safe(re, lre, &group->fanotify_data.access_list, list) {
- pr_debug("%s: found group=%p re=%p event=%p\n", __func__, group,
- re, re->event);
-
- list_del_init(&re->list);
- re->event->response = FAN_ALLOW;
+ list_for_each_entry_safe(event, next, &group->fanotify_data.access_list,
+ fae.fse.list) {
+ pr_debug("%s: found group=%p event=%p\n", __func__, group,
+ event);
- kmem_cache_free(fanotify_response_event_cache, re);
+ list_del_init(&event->fae.fse.list);
+ event->response = FAN_ALLOW;
}
- mutex_unlock(&group->fanotify_data.access_mutex);
+ spin_unlock(&group->fanotify_data.access_lock);
wake_up(&group->fanotify_data.access_waitq);
#endif
+
/* matches the fanotify_init->fsnotify_alloc_group */
- fsnotify_put_group(group);
+ fsnotify_destroy_group(group);
return 0;
}
@@ -427,7 +385,7 @@ static int fanotify_release(struct inode *ignored, struct file *file)
static long fanotify_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct fsnotify_group *group;
- struct fsnotify_event_holder *holder;
+ struct fsnotify_event *fsn_event;
void __user *p;
int ret = -ENOTTY;
size_t send_len = 0;
@@ -439,7 +397,7 @@ static long fanotify_ioctl(struct file *file, unsigned int cmd, unsigned long ar
switch (cmd) {
case FIONREAD:
mutex_lock(&group->notification_mutex);
- list_for_each_entry(holder, &group->notification_list, event_list)
+ list_for_each_entry(fsn_event, &group->notification_list, list)
send_len += FAN_EVENT_METADATA_LEN;
mutex_unlock(&group->notification_mutex);
ret = put_user(send_len, (int __user *) p);
@@ -450,6 +408,7 @@ static long fanotify_ioctl(struct file *file, unsigned int cmd, unsigned long ar
}
static const struct file_operations fanotify_fops = {
+ .show_fdinfo = fanotify_show_fdinfo,
.poll = fanotify_poll,
.read = fanotify_read,
.write = fanotify_write,
@@ -474,24 +433,22 @@ static int fanotify_find_path(int dfd, const char __user *filename,
dfd, filename, flags);
if (filename == NULL) {
- struct file *file;
- int fput_needed;
+ struct fd f = fdget(dfd);
ret = -EBADF;
- file = fget_light(dfd, &fput_needed);
- if (!file)
+ if (!f.file)
goto out;
ret = -ENOTDIR;
if ((flags & FAN_MARK_ONLYDIR) &&
- !(S_ISDIR(file->f_path.dentry->d_inode->i_mode))) {
- fput_light(file, fput_needed);
+ !(S_ISDIR(file_inode(f.file)->i_mode))) {
+ fdput(f);
goto out;
}
- *path = file->f_path;
+ *path = f.file->f_path;
path_get(path);
- fput_light(file, fput_needed);
+ fdput(f);
} else {
unsigned int lookup_flags = 0;
@@ -515,7 +472,8 @@ out:
static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark,
__u32 mask,
- unsigned int flags)
+ unsigned int flags,
+ int *destroy)
{
__u32 oldmask;
@@ -529,8 +487,7 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark,
}
spin_unlock(&fsn_mark->lock);
- if (!(oldmask & ~mask))
- fsnotify_destroy_mark(fsn_mark);
+ *destroy = !(oldmask & ~mask);
return mask & oldmask;
}
@@ -541,12 +498,21 @@ static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group,
{
struct fsnotify_mark *fsn_mark = NULL;
__u32 removed;
+ int destroy_mark;
+ mutex_lock(&group->mark_mutex);
fsn_mark = fsnotify_find_vfsmount_mark(group, mnt);
- if (!fsn_mark)
+ if (!fsn_mark) {
+ mutex_unlock(&group->mark_mutex);
return -ENOENT;
+ }
+
+ removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags,
+ &destroy_mark);
+ if (destroy_mark)
+ fsnotify_destroy_mark_locked(fsn_mark, group);
+ mutex_unlock(&group->mark_mutex);
- removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags);
fsnotify_put_mark(fsn_mark);
if (removed & real_mount(mnt)->mnt_fsnotify_mask)
fsnotify_recalc_vfsmount_mask(mnt);
@@ -560,12 +526,21 @@ static int fanotify_remove_inode_mark(struct fsnotify_group *group,
{
struct fsnotify_mark *fsn_mark = NULL;
__u32 removed;
+ int destroy_mark;
+ mutex_lock(&group->mark_mutex);
fsn_mark = fsnotify_find_inode_mark(group, inode);
- if (!fsn_mark)
+ if (!fsn_mark) {
+ mutex_unlock(&group->mark_mutex);
return -ENOENT;
+ }
+
+ removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags,
+ &destroy_mark);
+ if (destroy_mark)
+ fsnotify_destroy_mark_locked(fsn_mark, group);
+ mutex_unlock(&group->mark_mutex);
- removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags);
/* matches the fsnotify_find_inode_mark() */
fsnotify_put_mark(fsn_mark);
if (removed & inode->i_fsnotify_mask)
@@ -601,35 +576,55 @@ static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark,
return mask & ~oldmask;
}
+static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group,
+ struct inode *inode,
+ struct vfsmount *mnt)
+{
+ struct fsnotify_mark *mark;
+ int ret;
+
+ if (atomic_read(&group->num_marks) > group->fanotify_data.max_marks)
+ return ERR_PTR(-ENOSPC);
+
+ mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL);
+ if (!mark)
+ return ERR_PTR(-ENOMEM);
+
+ fsnotify_init_mark(mark, fanotify_free_mark);
+ ret = fsnotify_add_mark_locked(mark, group, inode, mnt, 0);
+ if (ret) {
+ fsnotify_put_mark(mark);
+ return ERR_PTR(ret);
+ }
+
+ return mark;
+}
+
+
static int fanotify_add_vfsmount_mark(struct fsnotify_group *group,
struct vfsmount *mnt, __u32 mask,
unsigned int flags)
{
struct fsnotify_mark *fsn_mark;
__u32 added;
- int ret = 0;
+ mutex_lock(&group->mark_mutex);
fsn_mark = fsnotify_find_vfsmount_mark(group, mnt);
if (!fsn_mark) {
- if (atomic_read(&group->num_marks) > group->fanotify_data.max_marks)
- return -ENOSPC;
-
- fsn_mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL);
- if (!fsn_mark)
- return -ENOMEM;
-
- fsnotify_init_mark(fsn_mark, fanotify_free_mark);
- ret = fsnotify_add_mark(fsn_mark, group, NULL, mnt, 0);
- if (ret)
- goto err;
+ fsn_mark = fanotify_add_new_mark(group, NULL, mnt);
+ if (IS_ERR(fsn_mark)) {
+ mutex_unlock(&group->mark_mutex);
+ return PTR_ERR(fsn_mark);
+ }
}
added = fanotify_mark_add_to_mask(fsn_mark, mask, flags);
+ mutex_unlock(&group->mark_mutex);
if (added & ~real_mount(mnt)->mnt_fsnotify_mask)
fsnotify_recalc_vfsmount_mask(mnt);
-err:
+
fsnotify_put_mark(fsn_mark);
- return ret;
+ return 0;
}
static int fanotify_add_inode_mark(struct fsnotify_group *group,
@@ -638,7 +633,6 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group,
{
struct fsnotify_mark *fsn_mark;
__u32 added;
- int ret = 0;
pr_debug("%s: group=%p inode=%p\n", __func__, group, inode);
@@ -652,27 +646,23 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group,
(atomic_read(&inode->i_writecount) > 0))
return 0;
+ mutex_lock(&group->mark_mutex);
fsn_mark = fsnotify_find_inode_mark(group, inode);
if (!fsn_mark) {
- if (atomic_read(&group->num_marks) > group->fanotify_data.max_marks)
- return -ENOSPC;
-
- fsn_mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL);
- if (!fsn_mark)
- return -ENOMEM;
-
- fsnotify_init_mark(fsn_mark, fanotify_free_mark);
- ret = fsnotify_add_mark(fsn_mark, group, inode, NULL, 0);
- if (ret)
- goto err;
+ fsn_mark = fanotify_add_new_mark(group, inode, NULL);
+ if (IS_ERR(fsn_mark)) {
+ mutex_unlock(&group->mark_mutex);
+ return PTR_ERR(fsn_mark);
+ }
}
added = fanotify_mark_add_to_mask(fsn_mark, mask, flags);
+ mutex_unlock(&group->mark_mutex);
if (added & ~inode->i_fsnotify_mask)
fsnotify_recalc_inode_mask(inode);
-err:
+
fsnotify_put_mark(fsn_mark);
- return ret;
+ return 0;
}
/* fanotify syscalls */
@@ -681,6 +671,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
struct fsnotify_group *group;
int f_flags, fd;
struct user_struct *user;
+ struct fanotify_event_info *oevent;
pr_debug("%s: flags=%d event_f_flags=%d\n",
__func__, flags, event_f_flags);
@@ -691,6 +682,18 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
if (flags & ~FAN_ALL_INIT_FLAGS)
return -EINVAL;
+ if (event_f_flags & ~FANOTIFY_INIT_ALL_EVENT_F_BITS)
+ return -EINVAL;
+
+ switch (event_f_flags & O_ACCMODE) {
+ case O_RDONLY:
+ case O_RDWR:
+ case O_WRONLY:
+ break;
+ default:
+ return -EINVAL;
+ }
+
user = get_current_user();
if (atomic_read(&user->fanotify_listeners) > FANOTIFY_DEFAULT_MAX_LISTENERS) {
free_uid(user);
@@ -713,9 +716,18 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
group->fanotify_data.user = user;
atomic_inc(&user->fanotify_listeners);
+ oevent = fanotify_alloc_event(NULL, FS_Q_OVERFLOW, NULL);
+ if (unlikely(!oevent)) {
+ fd = -ENOMEM;
+ goto out_destroy_group;
+ }
+ group->overflow_event = &oevent->fse;
+
+ if (force_o_largefile())
+ event_f_flags |= O_LARGEFILE;
group->fanotify_data.f_flags = event_f_flags;
#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
- mutex_init(&group->fanotify_data.access_mutex);
+ spin_lock_init(&group->fanotify_data.access_lock);
init_waitqueue_head(&group->fanotify_data.access_waitq);
INIT_LIST_HEAD(&group->fanotify_data.access_list);
atomic_set(&group->fanotify_data.bypass_perm, 0);
@@ -732,13 +744,13 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
break;
default:
fd = -EINVAL;
- goto out_put_group;
+ goto out_destroy_group;
}
if (flags & FAN_UNLIMITED_QUEUE) {
fd = -EPERM;
if (!capable(CAP_SYS_ADMIN))
- goto out_put_group;
+ goto out_destroy_group;
group->max_events = UINT_MAX;
} else {
group->max_events = FANOTIFY_DEFAULT_MAX_EVENTS;
@@ -747,7 +759,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
if (flags & FAN_UNLIMITED_MARKS) {
fd = -EPERM;
if (!capable(CAP_SYS_ADMIN))
- goto out_put_group;
+ goto out_destroy_group;
group->fanotify_data.max_marks = UINT_MAX;
} else {
group->fanotify_data.max_marks = FANOTIFY_DEFAULT_MAX_MARKS;
@@ -755,25 +767,25 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
fd = anon_inode_getfd("[fanotify]", &fanotify_fops, group, f_flags);
if (fd < 0)
- goto out_put_group;
+ goto out_destroy_group;
return fd;
-out_put_group:
- fsnotify_put_group(group);
+out_destroy_group:
+ fsnotify_destroy_group(group);
return fd;
}
-SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags,
- __u64 mask, int dfd,
- const char __user * pathname)
+SYSCALL_DEFINE5(fanotify_mark, int, fanotify_fd, unsigned int, flags,
+ __u64, mask, int, dfd,
+ const char __user *, pathname)
{
struct inode *inode = NULL;
struct vfsmount *mnt = NULL;
struct fsnotify_group *group;
- struct file *filp;
+ struct fd f;
struct path path;
- int ret, fput_needed;
+ int ret;
pr_debug("%s: fanotify_fd=%d flags=%x dfd=%d pathname=%p mask=%llx\n",
__func__, fanotify_fd, flags, dfd, pathname, mask);
@@ -789,7 +801,10 @@ SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags,
case FAN_MARK_REMOVE:
if (!mask)
return -EINVAL;
+ break;
case FAN_MARK_FLUSH:
+ if (flags & ~(FAN_MARK_MOUNT | FAN_MARK_FLUSH))
+ return -EINVAL;
break;
default:
return -EINVAL;
@@ -807,15 +822,15 @@ SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags,
#endif
return -EINVAL;
- filp = fget_light(fanotify_fd, &fput_needed);
- if (unlikely(!filp))
+ f = fdget(fanotify_fd);
+ if (unlikely(!f.file))
return -EBADF;
/* verify that this is indeed an fanotify instance */
ret = -EINVAL;
- if (unlikely(filp->f_op != &fanotify_fops))
+ if (unlikely(f.file->f_op != &fanotify_fops))
goto fput_and_out;
- group = filp->private_data;
+ group = f.file->private_data;
/*
* group->priority == FS_PRIO_0 == FAN_CLASS_NOTIF. These are not
@@ -826,6 +841,15 @@ SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags,
group->priority == FS_PRIO_0)
goto fput_and_out;
+ if (flags & FAN_MARK_FLUSH) {
+ ret = 0;
+ if (flags & FAN_MARK_MOUNT)
+ fsnotify_clear_vfsmount_marks_by_group(group);
+ else
+ fsnotify_clear_inode_marks_by_group(group);
+ goto fput_and_out;
+ }
+
ret = fanotify_find_path(dfd, pathname, &path, flags);
if (ret)
goto fput_and_out;
@@ -837,7 +861,7 @@ SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags,
mnt = path.mnt;
/* create/update an inode mark */
- switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE | FAN_MARK_FLUSH)) {
+ switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE)) {
case FAN_MARK_ADD:
if (flags & FAN_MARK_MOUNT)
ret = fanotify_add_vfsmount_mark(group, mnt, mask, flags);
@@ -850,31 +874,30 @@ SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags,
else
ret = fanotify_remove_inode_mark(group, inode, mask, flags);
break;
- case FAN_MARK_FLUSH:
- if (flags & FAN_MARK_MOUNT)
- fsnotify_clear_vfsmount_marks_by_group(group);
- else
- fsnotify_clear_inode_marks_by_group(group);
- break;
default:
ret = -EINVAL;
}
path_put(&path);
fput_and_out:
- fput_light(filp, fput_needed);
+ fdput(f);
return ret;
}
-#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
-asmlinkage long SyS_fanotify_mark(long fanotify_fd, long flags, __u64 mask,
- long dfd, long pathname)
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE6(fanotify_mark,
+ int, fanotify_fd, unsigned int, flags,
+ __u32, mask0, __u32, mask1, int, dfd,
+ const char __user *, pathname)
{
- return SYSC_fanotify_mark((int) fanotify_fd, (unsigned int) flags,
- mask, (int) dfd,
- (const char __user *) pathname);
+ return sys_fanotify_mark(fanotify_fd, flags,
+#ifdef __BIG_ENDIAN
+ ((__u64)mask0 << 32) | mask1,
+#else
+ ((__u64)mask1 << 32) | mask0,
+#endif
+ dfd, pathname);
}
-SYSCALL_ALIAS(sys_fanotify_mark, SyS_fanotify_mark);
#endif
/*
@@ -885,8 +908,11 @@ SYSCALL_ALIAS(sys_fanotify_mark, SyS_fanotify_mark);
static int __init fanotify_user_setup(void)
{
fanotify_mark_cache = KMEM_CACHE(fsnotify_mark, SLAB_PANIC);
- fanotify_response_event_cache = KMEM_CACHE(fanotify_response_event,
- SLAB_PANIC);
+ fanotify_event_cachep = KMEM_CACHE(fanotify_event_info, SLAB_PANIC);
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+ fanotify_perm_event_cachep = KMEM_CACHE(fanotify_perm_event_info,
+ SLAB_PANIC);
+#endif
return 0;
}