summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--fs/nfsd/filecache.c4
-rw-r--r--fs/notify/dnotify/dnotify.c4
-rw-r--r--fs/notify/fanotify/fanotify_user.c143
-rw-r--r--fs/notify/fdinfo.c20
-rw-r--r--fs/notify/fsnotify.c27
-rw-r--r--fs/notify/fsnotify.h39
-rw-r--r--fs/notify/inotify/inotify_user.c2
-rw-r--r--fs/notify/mark.c174
-rw-r--r--fs/super.c1
-rw-r--r--include/linux/fs.h14
-rw-r--r--include/linux/fsnotify.h21
-rw-r--r--include/linux/fsnotify_backend.h97
-rw-r--r--kernel/audit_tree.c2
-rw-r--r--kernel/audit_watch.c2
14 files changed, 334 insertions, 216 deletions
diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index ddd3e0d9cfa6..ad9083ca144b 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -159,8 +159,8 @@ nfsd_file_mark_find_or_create(struct nfsd_file *nf, struct inode *inode)
do {
fsnotify_group_lock(nfsd_file_fsnotify_group);
- mark = fsnotify_find_mark(&inode->i_fsnotify_marks,
- nfsd_file_fsnotify_group);
+ mark = fsnotify_find_inode_mark(inode,
+ nfsd_file_fsnotify_group);
if (mark) {
nfm = nfsd_file_mark_get(container_of(mark,
struct nfsd_file_mark,
diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c
index 3464fa7e8538..f3669403fabf 100644
--- a/fs/notify/dnotify/dnotify.c
+++ b/fs/notify/dnotify/dnotify.c
@@ -162,7 +162,7 @@ void dnotify_flush(struct file *filp, fl_owner_t id)
if (!S_ISDIR(inode->i_mode))
return;
- fsn_mark = fsnotify_find_mark(&inode->i_fsnotify_marks, dnotify_group);
+ fsn_mark = fsnotify_find_inode_mark(inode, dnotify_group);
if (!fsn_mark)
return;
dn_mark = container_of(fsn_mark, struct dnotify_mark, fsn_mark);
@@ -326,7 +326,7 @@ int fcntl_dirnotify(int fd, struct file *filp, unsigned int arg)
fsnotify_group_lock(dnotify_group);
/* add the new_fsn_mark or find an old one. */
- fsn_mark = fsnotify_find_mark(&inode->i_fsnotify_marks, dnotify_group);
+ fsn_mark = fsnotify_find_inode_mark(inode, dnotify_group);
if (fsn_mark) {
dn_mark = container_of(fsn_mark, struct dnotify_mark, fsn_mark);
spin_lock(&fsn_mark->lock);
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index fbdc63cc10d9..483a6a1255fb 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -502,7 +502,7 @@ static int copy_fid_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh,
}
/* Pad with 0's */
- WARN_ON_ONCE(len < 0 || len >= FANOTIFY_EVENT_ALIGN);
+ WARN_ON_ONCE(len >= FANOTIFY_EVENT_ALIGN);
if (len > 0 && clear_user(buf, len))
return -EFAULT;
@@ -1076,7 +1076,7 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark,
}
static int fanotify_remove_mark(struct fsnotify_group *group,
- fsnotify_connp_t *connp, __u32 mask,
+ void *obj, unsigned int obj_type, __u32 mask,
unsigned int flags, __u32 umask)
{
struct fsnotify_mark *fsn_mark = NULL;
@@ -1084,7 +1084,7 @@ static int fanotify_remove_mark(struct fsnotify_group *group,
int destroy_mark;
fsnotify_group_lock(group);
- fsn_mark = fsnotify_find_mark(connp, group);
+ fsn_mark = fsnotify_find_mark(obj, obj_type, group);
if (!fsn_mark) {
fsnotify_group_unlock(group);
return -ENOENT;
@@ -1105,30 +1105,6 @@ static int fanotify_remove_mark(struct fsnotify_group *group,
return 0;
}
-static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group,
- struct vfsmount *mnt, __u32 mask,
- unsigned int flags, __u32 umask)
-{
- return fanotify_remove_mark(group, &real_mount(mnt)->mnt_fsnotify_marks,
- mask, flags, umask);
-}
-
-static int fanotify_remove_sb_mark(struct fsnotify_group *group,
- struct super_block *sb, __u32 mask,
- unsigned int flags, __u32 umask)
-{
- return fanotify_remove_mark(group, &sb->s_fsnotify_marks, mask,
- flags, umask);
-}
-
-static int fanotify_remove_inode_mark(struct fsnotify_group *group,
- struct inode *inode, __u32 mask,
- unsigned int flags, __u32 umask)
-{
- return fanotify_remove_mark(group, &inode->i_fsnotify_marks, mask,
- flags, umask);
-}
-
static bool fanotify_mark_update_flags(struct fsnotify_mark *fsn_mark,
unsigned int fan_flags)
{
@@ -1249,7 +1225,7 @@ static int fanotify_set_mark_fsid(struct fsnotify_group *group,
}
static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group,
- fsnotify_connp_t *connp,
+ void *obj,
unsigned int obj_type,
unsigned int fan_flags,
struct fan_fsid *fsid)
@@ -1288,7 +1264,7 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group,
fan_mark->fsid.val[0] = fan_mark->fsid.val[1] = 0;
}
- ret = fsnotify_add_mark_locked(mark, connp, obj_type, 0);
+ ret = fsnotify_add_mark_locked(mark, obj, obj_type, 0);
if (ret)
goto out_put_mark;
@@ -1344,7 +1320,7 @@ static int fanotify_may_update_existing_mark(struct fsnotify_mark *fsn_mark,
}
static int fanotify_add_mark(struct fsnotify_group *group,
- fsnotify_connp_t *connp, unsigned int obj_type,
+ void *obj, unsigned int obj_type,
__u32 mask, unsigned int fan_flags,
struct fan_fsid *fsid)
{
@@ -1353,9 +1329,9 @@ static int fanotify_add_mark(struct fsnotify_group *group,
int ret = 0;
fsnotify_group_lock(group);
- fsn_mark = fsnotify_find_mark(connp, group);
+ fsn_mark = fsnotify_find_mark(obj, obj_type, group);
if (!fsn_mark) {
- fsn_mark = fanotify_add_new_mark(group, connp, obj_type,
+ fsn_mark = fanotify_add_new_mark(group, obj, obj_type,
fan_flags, fsid);
if (IS_ERR(fsn_mark)) {
fsnotify_group_unlock(group);
@@ -1392,42 +1368,6 @@ out:
return ret;
}
-static int fanotify_add_vfsmount_mark(struct fsnotify_group *group,
- struct vfsmount *mnt, __u32 mask,
- unsigned int flags, struct fan_fsid *fsid)
-{
- return fanotify_add_mark(group, &real_mount(mnt)->mnt_fsnotify_marks,
- FSNOTIFY_OBJ_TYPE_VFSMOUNT, mask, flags, fsid);
-}
-
-static int fanotify_add_sb_mark(struct fsnotify_group *group,
- struct super_block *sb, __u32 mask,
- unsigned int flags, struct fan_fsid *fsid)
-{
- return fanotify_add_mark(group, &sb->s_fsnotify_marks,
- FSNOTIFY_OBJ_TYPE_SB, mask, flags, fsid);
-}
-
-static int fanotify_add_inode_mark(struct fsnotify_group *group,
- struct inode *inode, __u32 mask,
- unsigned int flags, struct fan_fsid *fsid)
-{
- pr_debug("%s: group=%p inode=%p\n", __func__, group, inode);
-
- /*
- * If some other task has this inode open for write we should not add
- * an ignore mask, unless that ignore mask is supposed to survive
- * modification changes anyway.
- */
- if ((flags & FANOTIFY_MARK_IGNORE_BITS) &&
- !(flags & FAN_MARK_IGNORED_SURV_MODIFY) &&
- inode_is_open_for_write(inode))
- return 0;
-
- return fanotify_add_mark(group, &inode->i_fsnotify_marks,
- FSNOTIFY_OBJ_TYPE_INODE, mask, flags, fsid);
-}
-
static struct fsnotify_event *fanotify_alloc_overflow_event(void)
{
struct fanotify_event *oevent;
@@ -1576,13 +1516,13 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
INIT_LIST_HEAD(&group->fanotify_data.access_list);
switch (class) {
case FAN_CLASS_NOTIF:
- group->priority = FS_PRIO_0;
+ group->priority = FSNOTIFY_PRIO_NORMAL;
break;
case FAN_CLASS_CONTENT:
- group->priority = FS_PRIO_1;
+ group->priority = FSNOTIFY_PRIO_CONTENT;
break;
case FAN_CLASS_PRE_CONTENT:
- group->priority = FS_PRIO_2;
+ group->priority = FSNOTIFY_PRIO_PRE_CONTENT;
break;
default:
fd = -EINVAL;
@@ -1750,6 +1690,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
unsigned int mark_cmd = flags & FANOTIFY_MARK_CMD_BITS;
unsigned int ignore = flags & FANOTIFY_MARK_IGNORE_BITS;
unsigned int obj_type, fid_mode;
+ void *obj;
u32 umask = 0;
int ret;
@@ -1833,12 +1774,11 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
goto fput_and_out;
/*
- * group->priority == FS_PRIO_0 == FAN_CLASS_NOTIF. These are not
- * allowed to set permissions events.
+ * Permission events require minimum priority FAN_CLASS_CONTENT.
*/
ret = -EINVAL;
if (mask & FANOTIFY_PERM_EVENTS &&
- group->priority == FS_PRIO_0)
+ group->priority < FSNOTIFY_PRIO_CONTENT)
goto fput_and_out;
if (mask & FAN_FS_ERROR &&
@@ -1908,17 +1848,34 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
}
/* inode held in place by reference to path; group by fget on fd */
- if (mark_type == FAN_MARK_INODE)
+ if (mark_type == FAN_MARK_INODE) {
inode = path.dentry->d_inode;
- else
+ obj = inode;
+ } else {
mnt = path.mnt;
+ if (mark_type == FAN_MARK_MOUNT)
+ obj = mnt;
+ else
+ obj = mnt->mnt_sb;
+ }
- ret = mnt ? -EINVAL : -EISDIR;
- /* FAN_MARK_IGNORE requires SURV_MODIFY for sb/mount/dir marks */
- if (mark_cmd == FAN_MARK_ADD && ignore == FAN_MARK_IGNORE &&
- (mnt || S_ISDIR(inode->i_mode)) &&
- !(flags & FAN_MARK_IGNORED_SURV_MODIFY))
- goto path_put_and_out;
+ /*
+ * If some other task has this inode open for write we should not add
+ * an ignore mask, unless that ignore mask is supposed to survive
+ * modification changes anyway.
+ */
+ if (mark_cmd == FAN_MARK_ADD && (flags & FANOTIFY_MARK_IGNORE_BITS) &&
+ !(flags & FAN_MARK_IGNORED_SURV_MODIFY)) {
+ ret = mnt ? -EINVAL : -EISDIR;
+ /* FAN_MARK_IGNORE requires SURV_MODIFY for sb/mount/dir marks */
+ if (ignore == FAN_MARK_IGNORE &&
+ (mnt || S_ISDIR(inode->i_mode)))
+ goto path_put_and_out;
+
+ ret = 0;
+ if (inode && inode_is_open_for_write(inode))
+ goto path_put_and_out;
+ }
/* Mask out FAN_EVENT_ON_CHILD flag for sb/mount/non-dir marks */
if (mnt || !S_ISDIR(inode->i_mode)) {
@@ -1936,26 +1893,12 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
/* create/update an inode mark */
switch (mark_cmd) {
case FAN_MARK_ADD:
- if (mark_type == FAN_MARK_MOUNT)
- ret = fanotify_add_vfsmount_mark(group, mnt, mask,
- flags, fsid);
- else if (mark_type == FAN_MARK_FILESYSTEM)
- ret = fanotify_add_sb_mark(group, mnt->mnt_sb, mask,
- flags, fsid);
- else
- ret = fanotify_add_inode_mark(group, inode, mask,
- flags, fsid);
+ ret = fanotify_add_mark(group, obj, obj_type, mask, flags,
+ fsid);
break;
case FAN_MARK_REMOVE:
- if (mark_type == FAN_MARK_MOUNT)
- ret = fanotify_remove_vfsmount_mark(group, mnt, mask,
- flags, umask);
- else if (mark_type == FAN_MARK_FILESYSTEM)
- ret = fanotify_remove_sb_mark(group, mnt->mnt_sb, mask,
- flags, umask);
- else
- ret = fanotify_remove_inode_mark(group, inode, mask,
- flags, umask);
+ ret = fanotify_remove_mark(group, obj, obj_type, mask, flags,
+ umask);
break;
default:
ret = -EINVAL;
diff --git a/fs/notify/fdinfo.c b/fs/notify/fdinfo.c
index 5c430736ec12..dec553034027 100644
--- a/fs/notify/fdinfo.c
+++ b/fs/notify/fdinfo.c
@@ -41,29 +41,25 @@ static void show_fdinfo(struct seq_file *m, struct file *f,
#if defined(CONFIG_EXPORTFS)
static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
{
- struct {
- struct file_handle handle;
- u8 pad[MAX_HANDLE_SZ];
- } f;
+ DEFINE_FLEX(struct file_handle, f, f_handle, handle_bytes, MAX_HANDLE_SZ);
int size, ret, i;
- f.handle.handle_bytes = sizeof(f.pad);
- size = f.handle.handle_bytes >> 2;
+ size = f->handle_bytes >> 2;
- ret = exportfs_encode_fid(inode, (struct fid *)f.handle.f_handle, &size);
+ ret = exportfs_encode_fid(inode, (struct fid *)f->f_handle, &size);
if ((ret == FILEID_INVALID) || (ret < 0)) {
WARN_ONCE(1, "Can't encode file handler for inotify: %d\n", ret);
return;
}
- f.handle.handle_type = ret;
- f.handle.handle_bytes = size * sizeof(u32);
+ f->handle_type = ret;
+ f->handle_bytes = size * sizeof(u32);
seq_printf(m, "fhandle-bytes:%x fhandle-type:%x f_handle:",
- f.handle.handle_bytes, f.handle.handle_type);
+ f->handle_bytes, f->handle_type);
- for (i = 0; i < f.handle.handle_bytes; i++)
- seq_printf(m, "%02x", (int)f.handle.f_handle[i]);
+ for (i = 0; i < f->handle_bytes; i++)
+ seq_printf(m, "%02x", (int)f->f_handle[i]);
}
#else
static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 2fc105a72a8f..ff69ae24c4e8 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -89,11 +89,25 @@ static void fsnotify_unmount_inodes(struct super_block *sb)
void fsnotify_sb_delete(struct super_block *sb)
{
+ struct fsnotify_sb_info *sbinfo = fsnotify_sb_info(sb);
+
+ /* Were any marks ever added to any object on this sb? */
+ if (!sbinfo)
+ return;
+
fsnotify_unmount_inodes(sb);
fsnotify_clear_marks_by_sb(sb);
/* Wait for outstanding object references from connectors */
- wait_var_event(&sb->s_fsnotify_connectors,
- !atomic_long_read(&sb->s_fsnotify_connectors));
+ wait_var_event(fsnotify_sb_watched_objects(sb),
+ !atomic_long_read(fsnotify_sb_watched_objects(sb)));
+ WARN_ON(fsnotify_sb_has_priority_watchers(sb, FSNOTIFY_PRIO_CONTENT));
+ WARN_ON(fsnotify_sb_has_priority_watchers(sb,
+ FSNOTIFY_PRIO_PRE_CONTENT));
+}
+
+void fsnotify_sb_free(struct super_block *sb)
+{
+ kfree(sb->s_fsnotify_info);
}
/*
@@ -489,6 +503,7 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
{
const struct path *path = fsnotify_data_path(data, data_type);
struct super_block *sb = fsnotify_data_sb(data, data_type);
+ struct fsnotify_sb_info *sbinfo = fsnotify_sb_info(sb);
struct fsnotify_iter_info iter_info = {};
struct mount *mnt = NULL;
struct inode *inode2 = NULL;
@@ -525,7 +540,7 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
* SRCU because we have no references to any objects and do not
* need SRCU to keep them "alive".
*/
- if (!sb->s_fsnotify_marks &&
+ if ((!sbinfo || !sbinfo->sb_marks) &&
(!mnt || !mnt->mnt_fsnotify_marks) &&
(!inode || !inode->i_fsnotify_marks) &&
(!inode2 || !inode2->i_fsnotify_marks))
@@ -552,8 +567,10 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
iter_info.srcu_idx = srcu_read_lock(&fsnotify_mark_srcu);
- iter_info.marks[FSNOTIFY_ITER_TYPE_SB] =
- fsnotify_first_mark(&sb->s_fsnotify_marks);
+ if (sbinfo) {
+ iter_info.marks[FSNOTIFY_ITER_TYPE_SB] =
+ fsnotify_first_mark(&sbinfo->sb_marks);
+ }
if (mnt) {
iter_info.marks[FSNOTIFY_ITER_TYPE_VFSMOUNT] =
fsnotify_first_mark(&mnt->mnt_fsnotify_marks);
diff --git a/fs/notify/fsnotify.h b/fs/notify/fsnotify.h
index fde74eb333cc..2d059f789ee3 100644
--- a/fs/notify/fsnotify.h
+++ b/fs/notify/fsnotify.h
@@ -9,39 +9,58 @@
#include "../mount.h"
+/*
+ * fsnotify_connp_t is what we embed in objects which connector can be attached
+ * to.
+ */
+typedef struct fsnotify_mark_connector __rcu *fsnotify_connp_t;
+
static inline struct inode *fsnotify_conn_inode(
struct fsnotify_mark_connector *conn)
{
- return container_of(conn->obj, struct inode, i_fsnotify_marks);
+ return conn->obj;
}
static inline struct mount *fsnotify_conn_mount(
struct fsnotify_mark_connector *conn)
{
- return container_of(conn->obj, struct mount, mnt_fsnotify_marks);
+ return real_mount(conn->obj);
}
static inline struct super_block *fsnotify_conn_sb(
struct fsnotify_mark_connector *conn)
{
- return container_of(conn->obj, struct super_block, s_fsnotify_marks);
+ return conn->obj;
}
-static inline struct super_block *fsnotify_connector_sb(
- struct fsnotify_mark_connector *conn)
+static inline struct super_block *fsnotify_object_sb(void *obj,
+ enum fsnotify_obj_type obj_type)
{
- switch (conn->type) {
+ switch (obj_type) {
case FSNOTIFY_OBJ_TYPE_INODE:
- return fsnotify_conn_inode(conn)->i_sb;
+ return ((struct inode *)obj)->i_sb;
case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
- return fsnotify_conn_mount(conn)->mnt.mnt_sb;
+ return ((struct vfsmount *)obj)->mnt_sb;
case FSNOTIFY_OBJ_TYPE_SB:
- return fsnotify_conn_sb(conn);
+ return (struct super_block *)obj;
default:
return NULL;
}
}
+static inline struct super_block *fsnotify_connector_sb(
+ struct fsnotify_mark_connector *conn)
+{
+ return fsnotify_object_sb(conn->obj, conn->type);
+}
+
+static inline fsnotify_connp_t *fsnotify_sb_marks(struct super_block *sb)
+{
+ struct fsnotify_sb_info *sbinfo = fsnotify_sb_info(sb);
+
+ return sbinfo ? &sbinfo->sb_marks : NULL;
+}
+
/* destroy all events sitting in this groups notification queue */
extern void fsnotify_flush_notify(struct fsnotify_group *group);
@@ -67,7 +86,7 @@ static inline void fsnotify_clear_marks_by_mount(struct vfsmount *mnt)
/* run the list of all marks associated with sb and destroy them */
static inline void fsnotify_clear_marks_by_sb(struct super_block *sb)
{
- fsnotify_destroy_marks(&sb->s_fsnotify_marks);
+ fsnotify_destroy_marks(fsnotify_sb_marks(sb));
}
/*
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 85d8fdd55329..4ffc30606e0b 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -544,7 +544,7 @@ static int inotify_update_existing_watch(struct fsnotify_group *group,
int create = (arg & IN_MASK_CREATE);
int ret;
- fsn_mark = fsnotify_find_mark(&inode->i_fsnotify_marks, group);
+ fsn_mark = fsnotify_find_inode_mark(inode, group);
if (!fsn_mark)
return -ENOENT;
else if (create) {
diff --git a/fs/notify/mark.c b/fs/notify/mark.c
index d6944ff86ffa..c3eefa70633c 100644
--- a/fs/notify/mark.c
+++ b/fs/notify/mark.c
@@ -97,6 +97,21 @@ void fsnotify_get_mark(struct fsnotify_mark *mark)
refcount_inc(&mark->refcnt);
}
+static fsnotify_connp_t *fsnotify_object_connp(void *obj,
+ enum fsnotify_obj_type obj_type)
+{
+ switch (obj_type) {
+ case FSNOTIFY_OBJ_TYPE_INODE:
+ return &((struct inode *)obj)->i_fsnotify_marks;
+ case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
+ return &real_mount(obj)->mnt_fsnotify_marks;
+ case FSNOTIFY_OBJ_TYPE_SB:
+ return fsnotify_sb_marks(obj);
+ default:
+ return NULL;
+ }
+}
+
static __u32 *fsnotify_conn_mask_p(struct fsnotify_mark_connector *conn)
{
if (conn->type == FSNOTIFY_OBJ_TYPE_INODE)
@@ -116,10 +131,69 @@ __u32 fsnotify_conn_mask(struct fsnotify_mark_connector *conn)
return *fsnotify_conn_mask_p(conn);
}
+static void fsnotify_get_sb_watched_objects(struct super_block *sb)
+{
+ atomic_long_inc(fsnotify_sb_watched_objects(sb));
+}
+
+static void fsnotify_put_sb_watched_objects(struct super_block *sb)
+{
+ if (atomic_long_dec_and_test(fsnotify_sb_watched_objects(sb)))
+ wake_up_var(fsnotify_sb_watched_objects(sb));
+}
+
static void fsnotify_get_inode_ref(struct inode *inode)
{
ihold(inode);
- atomic_long_inc(&inode->i_sb->s_fsnotify_connectors);
+ fsnotify_get_sb_watched_objects(inode->i_sb);
+}
+
+static void fsnotify_put_inode_ref(struct inode *inode)
+{
+ fsnotify_put_sb_watched_objects(inode->i_sb);
+ iput(inode);
+}
+
+/*
+ * Grab or drop watched objects reference depending on whether the connector
+ * is attached and has any marks attached.
+ */
+static void fsnotify_update_sb_watchers(struct super_block *sb,
+ struct fsnotify_mark_connector *conn)
+{
+ struct fsnotify_sb_info *sbinfo = fsnotify_sb_info(sb);
+ bool is_watched = conn->flags & FSNOTIFY_CONN_FLAG_IS_WATCHED;
+ struct fsnotify_mark *first_mark = NULL;
+ unsigned int highest_prio = 0;
+
+ if (conn->obj)
+ first_mark = hlist_entry_safe(conn->list.first,
+ struct fsnotify_mark, obj_list);
+ if (first_mark)
+ highest_prio = first_mark->group->priority;
+ if (WARN_ON(highest_prio >= __FSNOTIFY_PRIO_NUM))
+ highest_prio = 0;
+
+ /*
+ * If the highest priority of group watching this object is prio,
+ * then watched object has a reference on counters [0..prio].
+ * Update priority >= 1 watched objects counters.
+ */
+ for (unsigned int p = conn->prio + 1; p <= highest_prio; p++)
+ atomic_long_inc(&sbinfo->watched_objects[p]);
+ for (unsigned int p = conn->prio; p > highest_prio; p--)
+ atomic_long_dec(&sbinfo->watched_objects[p]);
+ conn->prio = highest_prio;
+
+ /* Update priority >= 0 (a.k.a total) watched objects counter */
+ BUILD_BUG_ON(FSNOTIFY_PRIO_NORMAL != 0);
+ if (first_mark && !is_watched) {
+ conn->flags |= FSNOTIFY_CONN_FLAG_IS_WATCHED;
+ fsnotify_get_sb_watched_objects(sb);
+ } else if (!first_mark && is_watched) {
+ conn->flags &= ~FSNOTIFY_CONN_FLAG_IS_WATCHED;
+ fsnotify_put_sb_watched_objects(sb);
+ }
}
/*
@@ -213,35 +287,12 @@ static void fsnotify_connector_destroy_workfn(struct work_struct *work)
}
}
-static void fsnotify_put_inode_ref(struct inode *inode)
-{
- struct super_block *sb = inode->i_sb;
-
- iput(inode);
- if (atomic_long_dec_and_test(&sb->s_fsnotify_connectors))
- wake_up_var(&sb->s_fsnotify_connectors);
-}
-
-static void fsnotify_get_sb_connectors(struct fsnotify_mark_connector *conn)
-{
- struct super_block *sb = fsnotify_connector_sb(conn);
-
- if (sb)
- atomic_long_inc(&sb->s_fsnotify_connectors);
-}
-
-static void fsnotify_put_sb_connectors(struct fsnotify_mark_connector *conn)
-{
- struct super_block *sb = fsnotify_connector_sb(conn);
-
- if (sb && atomic_long_dec_and_test(&sb->s_fsnotify_connectors))
- wake_up_var(&sb->s_fsnotify_connectors);
-}
-
static void *fsnotify_detach_connector_from_object(
struct fsnotify_mark_connector *conn,
unsigned int *type)
{
+ fsnotify_connp_t *connp = fsnotify_object_connp(conn->obj, conn->type);
+ struct super_block *sb = fsnotify_connector_sb(conn);
struct inode *inode = NULL;
*type = conn->type;
@@ -261,10 +312,10 @@ static void *fsnotify_detach_connector_from_object(
fsnotify_conn_sb(conn)->s_fsnotify_mask = 0;
}
- fsnotify_put_sb_connectors(conn);
- rcu_assign_pointer(*(conn->obj), NULL);
+ rcu_assign_pointer(*connp, NULL);
conn->obj = NULL;
conn->type = FSNOTIFY_OBJ_TYPE_DETACHED;
+ fsnotify_update_sb_watchers(sb, conn);
return inode;
}
@@ -316,6 +367,11 @@ void fsnotify_put_mark(struct fsnotify_mark *mark)
objp = fsnotify_detach_connector_from_object(conn, &type);
free_conn = true;
} else {
+ struct super_block *sb = fsnotify_connector_sb(conn);
+
+ /* Update watched objects after detaching mark */
+ if (sb)
+ fsnotify_update_sb_watchers(sb, conn);
objp = __fsnotify_recalc_mask(conn);
type = conn->type;
}
@@ -536,8 +592,28 @@ int fsnotify_compare_groups(struct fsnotify_group *a, struct fsnotify_group *b)
return -1;
}
+static int fsnotify_attach_info_to_sb(struct super_block *sb)
+{
+ struct fsnotify_sb_info *sbinfo;
+
+ /* sb info is freed on fsnotify_sb_delete() */
+ sbinfo = kzalloc(sizeof(*sbinfo), GFP_KERNEL);
+ if (!sbinfo)
+ return -ENOMEM;
+
+ /*
+ * cmpxchg() provides the barrier so that callers of fsnotify_sb_info()
+ * will observe an initialized structure
+ */
+ if (cmpxchg(&sb->s_fsnotify_info, NULL, sbinfo)) {
+ /* Someone else created sbinfo for us */
+ kfree(sbinfo);
+ }
+ return 0;
+}
+
static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp,
- unsigned int obj_type)
+ void *obj, unsigned int obj_type)
{
struct fsnotify_mark_connector *conn;
@@ -547,10 +623,9 @@ static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp,
spin_lock_init(&conn->lock);
INIT_HLIST_HEAD(&conn->list);
conn->flags = 0;
+ conn->prio = 0;
conn->type = obj_type;
- conn->obj = connp;
- conn->flags = 0;
- fsnotify_get_sb_connectors(conn);
+ conn->obj = obj;
/*
* cmpxchg() provides the barrier so that readers of *connp can see
@@ -558,10 +633,8 @@ static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp,
*/
if (cmpxchg(connp, NULL, conn)) {
/* Someone else created list structure for us */
- fsnotify_put_sb_connectors(conn);
kmem_cache_free(fsnotify_mark_connector_cachep, conn);
}
-
return 0;
}
@@ -598,24 +671,36 @@ out:
* to which group and for which inodes. These marks are ordered according to
* priority, highest number first, and then by the group's location in memory.
*/
-static int fsnotify_add_mark_list(struct fsnotify_mark *mark,
- fsnotify_connp_t *connp,
+static int fsnotify_add_mark_list(struct fsnotify_mark *mark, void *obj,
unsigned int obj_type, int add_flags)
{
+ struct super_block *sb = fsnotify_object_sb(obj, obj_type);
struct fsnotify_mark *lmark, *last = NULL;
struct fsnotify_mark_connector *conn;
+ fsnotify_connp_t *connp;
int cmp;
int err = 0;
if (WARN_ON(!fsnotify_valid_obj_type(obj_type)))
return -EINVAL;
+ /*
+ * Attach the sb info before attaching a connector to any object on sb.
+ * The sb info will remain attached as long as sb lives.
+ */
+ if (!fsnotify_sb_info(sb)) {
+ err = fsnotify_attach_info_to_sb(sb);
+ if (err)
+ return err;
+ }
+
+ connp = fsnotify_object_connp(obj, obj_type);
restart:
spin_lock(&mark->lock);
conn = fsnotify_grab_connector(connp);
if (!conn) {
spin_unlock(&mark->lock);
- err = fsnotify_attach_connector_to_object(connp, obj_type);
+ err = fsnotify_attach_connector_to_object(connp, obj, obj_type);
if (err)
return err;
goto restart;
@@ -649,6 +734,7 @@ restart:
/* mark should be the last entry. last is the current last entry */
hlist_add_behind_rcu(&mark->obj_list, &last->obj_list);
added:
+ fsnotify_update_sb_watchers(sb, conn);
/*
* Since connector is attached to object using cmpxchg() we are
* guaranteed that connector initialization is fully visible by anyone
@@ -667,7 +753,7 @@ out_err:
* event types should be delivered to which group.
*/
int fsnotify_add_mark_locked(struct fsnotify_mark *mark,
- fsnotify_connp_t *connp, unsigned int obj_type,
+ void *obj, unsigned int obj_type,
int add_flags)
{
struct fsnotify_group *group = mark->group;
@@ -688,7 +774,7 @@ int fsnotify_add_mark_locked(struct fsnotify_mark *mark,
fsnotify_get_mark(mark); /* for g_list */
spin_unlock(&mark->lock);
- ret = fsnotify_add_mark_list(mark, connp, obj_type, add_flags);
+ ret = fsnotify_add_mark_list(mark, obj, obj_type, add_flags);
if (ret)
goto err;
@@ -706,14 +792,14 @@ err:
return ret;
}
-int fsnotify_add_mark(struct fsnotify_mark *mark, fsnotify_connp_t *connp,
+int fsnotify_add_mark(struct fsnotify_mark *mark, void *obj,
unsigned int obj_type, int add_flags)
{
int ret;
struct fsnotify_group *group = mark->group;
fsnotify_group_lock(group);
- ret = fsnotify_add_mark_locked(mark, connp, obj_type, add_flags);
+ ret = fsnotify_add_mark_locked(mark, obj, obj_type, add_flags);
fsnotify_group_unlock(group);
return ret;
}
@@ -723,12 +809,16 @@ EXPORT_SYMBOL_GPL(fsnotify_add_mark);
* Given a list of marks, find the mark associated with given group. If found
* take a reference to that mark and return it, else return NULL.
*/
-struct fsnotify_mark *fsnotify_find_mark(fsnotify_connp_t *connp,
+struct fsnotify_mark *fsnotify_find_mark(void *obj, unsigned int obj_type,
struct fsnotify_group *group)
{
+ fsnotify_connp_t *connp = fsnotify_object_connp(obj, obj_type);
struct fsnotify_mark_connector *conn;
struct fsnotify_mark *mark;
+ if (!connp)
+ return NULL;
+
conn = fsnotify_grab_connector(connp);
if (!conn)
return NULL;
diff --git a/fs/super.c b/fs/super.c
index 69ce6c600968..b72f1d288e95 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -274,6 +274,7 @@ static void destroy_super_work(struct work_struct *work)
{
struct super_block *s = container_of(work, struct super_block,
destroy_work);
+ fsnotify_sb_free(s);
security_sb_free(s);
put_user_ns(s->s_user_ns);
kfree(s->s_subtype);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index a7e7e37ba417..f1cc6d39b61f 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -73,6 +73,8 @@ struct fscrypt_inode_info;
struct fscrypt_operations;
struct fsverity_info;
struct fsverity_operations;
+struct fsnotify_mark_connector;
+struct fsnotify_sb_info;
struct fs_context;
struct fs_parameter_spec;
struct fileattr;
@@ -618,8 +620,6 @@ is_uncached_acl(struct posix_acl *acl)
#define IOP_XATTR 0x0008
#define IOP_DEFAULT_READLINK 0x0010
-struct fsnotify_mark_connector;
-
/*
* Keep mostly read-only and often accessed (especially for
* the RCU path lookup and 'stat' data) fields at the beginning
@@ -1248,7 +1248,7 @@ struct super_block {
/*
* Keep s_fs_info, s_time_gran, s_fsnotify_mask, and
- * s_fsnotify_marks together for cache efficiency. They are frequently
+ * s_fsnotify_info together for cache efficiency. They are frequently
* accessed and rarely modified.
*/
void *s_fs_info; /* Filesystem private info */
@@ -1260,7 +1260,7 @@ struct super_block {
time64_t s_time_max;
#ifdef CONFIG_FSNOTIFY
__u32 s_fsnotify_mask;
- struct fsnotify_mark_connector __rcu *s_fsnotify_marks;
+ struct fsnotify_sb_info *s_fsnotify_info;
#endif
/*
@@ -1301,12 +1301,6 @@ struct super_block {
/* Number of inodes with nlink == 0 but still referenced */
atomic_long_t s_remove_count;
- /*
- * Number of inode/mount/sb objects that are being watched, note that
- * inodes objects are currently double-accounted.
- */
- atomic_long_t s_fsnotify_connectors;
-
/* Read-only state of the superblock is being changed */
int s_readonly_remount;
diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h
index 1a9de119a0f7..4da80e92f804 100644
--- a/include/linux/fsnotify.h
+++ b/include/linux/fsnotify.h
@@ -17,10 +17,23 @@
#include <linux/slab.h>
#include <linux/bug.h>
+/* Are there any inode/mount/sb objects watched with priority prio or above? */
+static inline bool fsnotify_sb_has_priority_watchers(struct super_block *sb,
+ int prio)
+{
+ struct fsnotify_sb_info *sbinfo = fsnotify_sb_info(sb);
+
+ /* Were any marks ever added to any object on this sb? */
+ if (!sbinfo)
+ return false;
+
+ return atomic_long_read(&sbinfo->watched_objects[prio]);
+}
+
/* Are there any inode/mount/sb objects that are being watched at all? */
static inline bool fsnotify_sb_has_watchers(struct super_block *sb)
{
- return atomic_long_read(&sb->s_fsnotify_connectors);
+ return fsnotify_sb_has_priority_watchers(sb, 0);
}
/*
@@ -103,6 +116,12 @@ static inline int fsnotify_file(struct file *file, __u32 mask)
return 0;
path = &file->f_path;
+ /* Permission events require group prio >= FSNOTIFY_PRIO_CONTENT */
+ if (mask & ALL_FSNOTIFY_PERM_EVENTS &&
+ !fsnotify_sb_has_priority_watchers(path->dentry->d_sb,
+ FSNOTIFY_PRIO_CONTENT))
+ return 0;
+
return fsnotify_parent(path->dentry, mask, path, FSNOTIFY_EVENT_PATH);
}
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 8f40c349b228..4dd6143db271 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -177,6 +177,17 @@ struct fsnotify_event {
};
/*
+ * fsnotify group priorities.
+ * Events are sent in order from highest priority to lowest priority.
+ */
+enum fsnotify_group_prio {
+ FSNOTIFY_PRIO_NORMAL = 0, /* normal notifiers, no permissions */
+ FSNOTIFY_PRIO_CONTENT, /* fanotify permission events */
+ FSNOTIFY_PRIO_PRE_CONTENT, /* fanotify pre-content events */
+ __FSNOTIFY_PRIO_NUM
+};
+
+/*
* A group is a "thing" that wants to receive notification about filesystem
* events. The mask holds the subset of event types this group cares about.
* refcnt on a group is up to the implementor and at any moment if it goes 0
@@ -201,14 +212,7 @@ struct fsnotify_group {
wait_queue_head_t notification_waitq; /* read() on the notification file blocks on this waitq */
unsigned int q_len; /* events on the queue */
unsigned int max_events; /* maximum events allowed on the list */
- /*
- * Valid fsnotify group priorities. Events are send in order from highest
- * priority to lowest priority. We default to the lowest priority.
- */
- #define FS_PRIO_0 0 /* normal notifiers, no permissions */
- #define FS_PRIO_1 1 /* fanotify content based access control */
- #define FS_PRIO_2 2 /* fanotify pre-content access */
- unsigned int priority;
+ enum fsnotify_group_prio priority; /* priority for sending events */
bool shutdown; /* group is being shut down, don't queue more events */
#define FSNOTIFY_GROUP_USER 0x01 /* user allocated group */
@@ -457,13 +461,6 @@ FSNOTIFY_ITER_FUNCS(sb, SB)
type++)
/*
- * fsnotify_connp_t is what we embed in objects which connector can be attached
- * to. fsnotify_connp_t * is how we refer from connector back to object.
- */
-struct fsnotify_mark_connector;
-typedef struct fsnotify_mark_connector __rcu *fsnotify_connp_t;
-
-/*
* Inode/vfsmount/sb point to this structure which tracks all marks attached to
* the inode/vfsmount/sb. The reference to inode/vfsmount/sb is held by this
* structure. We destroy this structure when there are no more marks attached
@@ -471,12 +468,14 @@ typedef struct fsnotify_mark_connector __rcu *fsnotify_connp_t;
*/
struct fsnotify_mark_connector {
spinlock_t lock;
- unsigned short type; /* Type of object [lock] */
+ unsigned char type; /* Type of object [lock] */
+ unsigned char prio; /* Highest priority group */
+#define FSNOTIFY_CONN_FLAG_IS_WATCHED 0x01
#define FSNOTIFY_CONN_FLAG_HAS_IREF 0x02
unsigned short flags; /* flags [lock] */
union {
/* Object pointer [lock] */
- fsnotify_connp_t *obj;
+ void *obj;
/* Used listing heads to free after srcu period expires */
struct fsnotify_mark_connector *destroy_next;
};
@@ -484,6 +483,37 @@ struct fsnotify_mark_connector {
};
/*
+ * Container for per-sb fsnotify state (sb marks and more).
+ * Attached lazily on first marked object on the sb and freed when killing sb.
+ */
+struct fsnotify_sb_info {
+ struct fsnotify_mark_connector __rcu *sb_marks;
+ /*
+ * Number of inode/mount/sb objects that are being watched in this sb.
+ * Note that inodes objects are currently double-accounted.
+ *
+ * The value in watched_objects[prio] is the number of objects that are
+ * watched by groups of priority >= prio, so watched_objects[0] is the
+ * total number of watched objects in this sb.
+ */
+ atomic_long_t watched_objects[__FSNOTIFY_PRIO_NUM];
+};
+
+static inline struct fsnotify_sb_info *fsnotify_sb_info(struct super_block *sb)
+{
+#ifdef CONFIG_FSNOTIFY
+ return READ_ONCE(sb->s_fsnotify_info);
+#else
+ return NULL;
+#endif
+}
+
+static inline atomic_long_t *fsnotify_sb_watched_objects(struct super_block *sb)
+{
+ return &fsnotify_sb_info(sb)->watched_objects[0];
+}
+
+/*
* A mark is simply an object attached to an in core inode which allows an
* fsnotify listener to indicate they are either no longer interested in events
* of a type matching mask or only interested in those events.
@@ -546,6 +576,7 @@ extern int __fsnotify_parent(struct dentry *dentry, __u32 mask, const void *data
extern void __fsnotify_inode_delete(struct inode *inode);
extern void __fsnotify_vfsmount_delete(struct vfsmount *mnt);
extern void fsnotify_sb_delete(struct super_block *sb);
+extern void fsnotify_sb_free(struct super_block *sb);
extern u32 fsnotify_get_cookie(void);
static inline __u32 fsnotify_parent_needed_mask(__u32 mask)
@@ -758,30 +789,35 @@ extern void fsnotify_recalc_mask(struct fsnotify_mark_connector *conn);
extern void fsnotify_init_mark(struct fsnotify_mark *mark,
struct fsnotify_group *group);
/* Find mark belonging to given group in the list of marks */
-extern struct fsnotify_mark *fsnotify_find_mark(fsnotify_connp_t *connp,
- struct fsnotify_group *group);
+struct fsnotify_mark *fsnotify_find_mark(void *obj, unsigned int obj_type,
+ struct fsnotify_group *group);
/* attach the mark to the object */
-extern int fsnotify_add_mark(struct fsnotify_mark *mark,
- fsnotify_connp_t *connp, unsigned int obj_type,
- int add_flags);
-extern int fsnotify_add_mark_locked(struct fsnotify_mark *mark,
- fsnotify_connp_t *connp,
- unsigned int obj_type, int add_flags);
+int fsnotify_add_mark(struct fsnotify_mark *mark, void *obj,
+ unsigned int obj_type, int add_flags);
+int fsnotify_add_mark_locked(struct fsnotify_mark *mark, void *obj,
+ unsigned int obj_type, int add_flags);
/* attach the mark to the inode */
static inline int fsnotify_add_inode_mark(struct fsnotify_mark *mark,
struct inode *inode,
int add_flags)
{
- return fsnotify_add_mark(mark, &inode->i_fsnotify_marks,
- FSNOTIFY_OBJ_TYPE_INODE, add_flags);
+ return fsnotify_add_mark(mark, inode, FSNOTIFY_OBJ_TYPE_INODE,
+ add_flags);
}
static inline int fsnotify_add_inode_mark_locked(struct fsnotify_mark *mark,
struct inode *inode,
int add_flags)
{
- return fsnotify_add_mark_locked(mark, &inode->i_fsnotify_marks,
- FSNOTIFY_OBJ_TYPE_INODE, add_flags);
+ return fsnotify_add_mark_locked(mark, inode, FSNOTIFY_OBJ_TYPE_INODE,
+ add_flags);
+}
+
+static inline struct fsnotify_mark *fsnotify_find_inode_mark(
+ struct inode *inode,
+ struct fsnotify_group *group)
+{
+ return fsnotify_find_mark(inode, FSNOTIFY_OBJ_TYPE_INODE, group);
}
/* given a group and a mark, flag mark to be freed when all references are dropped */
@@ -845,6 +881,9 @@ static inline void __fsnotify_vfsmount_delete(struct vfsmount *mnt)
static inline void fsnotify_sb_delete(struct super_block *sb)
{}
+static inline void fsnotify_sb_free(struct super_block *sb)
+{}
+
static inline void fsnotify_update_flags(struct dentry *dentry)
{}
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index 1b07e6f12a07..f2f38903b2fe 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -463,7 +463,7 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree)
int n;
fsnotify_group_lock(audit_tree_group);
- mark = fsnotify_find_mark(&inode->i_fsnotify_marks, audit_tree_group);
+ mark = fsnotify_find_inode_mark(inode, audit_tree_group);
if (!mark)
return create_chunk(inode, tree);
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
index 7a98cd176a12..7f358740e958 100644
--- a/kernel/audit_watch.c
+++ b/kernel/audit_watch.c
@@ -90,7 +90,7 @@ static inline struct audit_parent *audit_find_parent(struct inode *inode)
struct audit_parent *parent = NULL;
struct fsnotify_mark *entry;
- entry = fsnotify_find_mark(&inode->i_fsnotify_marks, audit_watch_group);
+ entry = fsnotify_find_inode_mark(inode, audit_watch_group);
if (entry)
parent = container_of(entry, struct audit_parent, mark);