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-rw-r--r--fs/notify/dnotify/dnotify.c8
-rw-r--r--fs/notify/fanotify/fanotify.c8
-rw-r--r--fs/notify/fsnotify.c87
3 files changed, 64 insertions, 39 deletions
diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c
index c4cdaf5fa7ed..9fb73bafd41d 100644
--- a/fs/notify/dnotify/dnotify.c
+++ b/fs/notify/dnotify/dnotify.c
@@ -308,6 +308,10 @@ int fcntl_dirnotify(int fd, struct file *filp, unsigned int arg)
goto out_err;
}
+ error = file_f_owner_allocate(filp);
+ if (error)
+ goto out_err;
+
/* new fsnotify mark, we expect most fcntl calls to add a new mark */
new_dn_mark = kmem_cache_alloc(dnotify_mark_cache, GFP_KERNEL);
if (!new_dn_mark) {
@@ -315,10 +319,6 @@ int fcntl_dirnotify(int fd, struct file *filp, unsigned int arg)
goto out_err;
}
- error = file_f_owner_allocate(filp);
- if (error)
- goto out_err;
-
/* set up the new_fsn_mark and new_dn_mark */
new_fsn_mark = &new_dn_mark->fsn_mark;
fsnotify_init_mark(new_fsn_mark, dnotify_group);
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index 3083643b864b..bfe884d624e7 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -454,7 +454,13 @@ static int fanotify_encode_fh(struct fanotify_fh *fh, struct inode *inode,
dwords = fh_len >> 2;
type = exportfs_encode_fid(inode, buf, &dwords);
err = -EINVAL;
- if (type <= 0 || type == FILEID_INVALID || fh_len != dwords << 2)
+ /*
+ * Unlike file_handle, type and len of struct fanotify_fh are u8.
+ * Traditionally, filesystem return handle_type < 0xff, but there
+ * is no enforecement for that in vfs.
+ */
+ BUILD_BUG_ON(MAX_HANDLE_SZ > 0xff || FILEID_INVALID > 0xff);
+ if (type <= 0 || type >= FILEID_INVALID || fh_len != dwords << 2)
goto out_err;
fh->type = type;
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index e2b4f17a48bb..079b868552c2 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -199,8 +199,8 @@ static bool fsnotify_event_needs_parent(struct inode *inode, __u32 mnt_mask,
}
/* Are there any inode/mount/sb objects that watch for these events? */
-static inline bool fsnotify_object_watched(struct inode *inode, __u32 mnt_mask,
- __u32 mask)
+static inline __u32 fsnotify_object_watched(struct inode *inode, __u32 mnt_mask,
+ __u32 mask)
{
__u32 marks_mask = READ_ONCE(inode->i_fsnotify_mask) | mnt_mask |
READ_ONCE(inode->i_sb->s_fsnotify_mask);
@@ -656,20 +656,20 @@ EXPORT_SYMBOL_GPL(fsnotify);
#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
/*
- * At open time we check fsnotify_sb_has_priority_watchers() and set the
- * FMODE_NONOTIFY_ mode bits accordignly.
+ * At open time we check fsnotify_sb_has_priority_watchers(), call the open perm
+ * hook and set the FMODE_NONOTIFY_ mode bits accordignly.
* Later, fsnotify permission hooks do not check if there are permission event
* watches, but that there were permission event watches at open time.
*/
-void file_set_fsnotify_mode_from_watchers(struct file *file)
+int fsnotify_open_perm_and_set_mode(struct file *file)
{
struct dentry *dentry = file->f_path.dentry, *parent;
struct super_block *sb = dentry->d_sb;
- __u32 mnt_mask, p_mask;
+ __u32 mnt_mask, p_mask = 0;
/* Is it a file opened by fanotify? */
if (FMODE_FSNOTIFY_NONE(file->f_mode))
- return;
+ return 0;
/*
* Permission events is a super set of pre-content events, so if there
@@ -679,45 +679,64 @@ void file_set_fsnotify_mode_from_watchers(struct file *file)
if (likely(!fsnotify_sb_has_priority_watchers(sb,
FSNOTIFY_PRIO_CONTENT))) {
file_set_fsnotify_mode(file, FMODE_NONOTIFY_PERM);
- return;
+ return 0;
}
/*
- * If there are permission event watchers but no pre-content event
- * watchers, set FMODE_NONOTIFY | FMODE_NONOTIFY_PERM to indicate that.
+ * OK, there are some permission event watchers. Check if anybody is
+ * watching for permission events on *this* file.
*/
- if ((!d_is_dir(dentry) && !d_is_reg(dentry)) ||
- likely(!fsnotify_sb_has_priority_watchers(sb,
- FSNOTIFY_PRIO_PRE_CONTENT))) {
- file_set_fsnotify_mode(file, FMODE_NONOTIFY | FMODE_NONOTIFY_PERM);
- return;
+ mnt_mask = READ_ONCE(real_mount(file->f_path.mnt)->mnt_fsnotify_mask);
+ p_mask = fsnotify_object_watched(d_inode(dentry), mnt_mask,
+ ALL_FSNOTIFY_PERM_EVENTS);
+ if (dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED) {
+ parent = dget_parent(dentry);
+ p_mask |= fsnotify_inode_watches_children(d_inode(parent));
+ dput(parent);
}
/*
- * OK, there are some pre-content watchers. Check if anybody is
- * watching for pre-content events on *this* file.
+ * Legacy FAN_ACCESS_PERM events have very high performance overhead,
+ * so unlikely to be used in the wild. If they are used there will be
+ * no optimizations at all.
*/
- mnt_mask = READ_ONCE(real_mount(file->f_path.mnt)->mnt_fsnotify_mask);
- if (unlikely(fsnotify_object_watched(d_inode(dentry), mnt_mask,
- FSNOTIFY_PRE_CONTENT_EVENTS))) {
- /* Enable pre-content events */
+ if (unlikely(p_mask & FS_ACCESS_PERM)) {
+ /* Enable all permission and pre-content events */
file_set_fsnotify_mode(file, 0);
- return;
+ goto open_perm;
}
- /* Is parent watching for pre-content events on this file? */
- if (dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED) {
- parent = dget_parent(dentry);
- p_mask = fsnotify_inode_watches_children(d_inode(parent));
- dput(parent);
- if (p_mask & FSNOTIFY_PRE_CONTENT_EVENTS) {
- /* Enable pre-content events */
- file_set_fsnotify_mode(file, 0);
- return;
- }
+ /*
+ * Pre-content events are only supported on regular files.
+ * If there are pre-content event watchers and no permission access
+ * watchers, set FMODE_NONOTIFY | FMODE_NONOTIFY_PERM to indicate that.
+ * That is the common case with HSM service.
+ */
+ if (d_is_reg(dentry) && (p_mask & FSNOTIFY_PRE_CONTENT_EVENTS)) {
+ file_set_fsnotify_mode(file, FMODE_NONOTIFY |
+ FMODE_NONOTIFY_PERM);
+ goto open_perm;
}
- /* Nobody watching for pre-content events from this file */
- file_set_fsnotify_mode(file, FMODE_NONOTIFY | FMODE_NONOTIFY_PERM);
+
+ /* Nobody watching permission and pre-content events on this file */
+ file_set_fsnotify_mode(file, FMODE_NONOTIFY_PERM);
+
+open_perm:
+ /*
+ * Send open perm events depending on object masks and regardless of
+ * FMODE_NONOTIFY_PERM.
+ */
+ if (file->f_flags & __FMODE_EXEC && p_mask & FS_OPEN_EXEC_PERM) {
+ int ret = fsnotify_path(&file->f_path, FS_OPEN_EXEC_PERM);
+
+ if (ret)
+ return ret;
+ }
+
+ if (p_mask & FS_OPEN_PERM)
+ return fsnotify_path(&file->f_path, FS_OPEN_PERM);
+
+ return 0;
}
#endif
generated by cgit (git 2.34.1) at 2025-08-01 13:39:09 +0000