5.4-stable review patch. If anyone has any objections, please let me know.
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From: Jan Kara jack@suse.cz
commit 702eb71fd6501b3566283f8c96d7ccc6ddd662e9 upstream.
Currently we will not generate FS_OPEN events for O_PATH file descriptors but we will generate FS_CLOSE events for them. This is asymmetry is confusing. Arguably no fsnotify events should be generated for O_PATH file descriptors as they cannot be used to access or modify file content, they are just convenient handles to file objects like paths. So fix the asymmetry by stopping to generate FS_CLOSE for O_PATH file descriptors.
Cc: stable@vger.kernel.org Signed-off-by: Jan Kara jack@suse.cz Link: https://lore.kernel.org/r/20240617162303.1596-1-jack@suse.cz Reviewed-by: Amir Goldstein amir73il@gmail.com Signed-off-by: Christian Brauner brauner@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/linux/fsnotify.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
--- a/include/linux/fsnotify.h +++ b/include/linux/fsnotify.h @@ -62,7 +62,13 @@ static inline int fsnotify_perm(struct f struct inode *inode = file_inode(file); __u32 fsnotify_mask = 0;
- if (file->f_mode & FMODE_NONOTIFY) + /* + * FMODE_NONOTIFY are fds generated by fanotify itself which should not + * generate new events. We also don't want to generate events for + * FMODE_PATH fds (involves open & close events) as they are just + * handle creation / destruction events and not "real" file events. + */ + if (file->f_mode & (FMODE_NONOTIFY | FMODE_PATH)) return 0; if (!(mask & (MAY_READ | MAY_OPEN))) return 0;