[ Upstream commit d989903058a83e8536cc7aadf9256a47d5c173fe ]
Overlayfs "fake" path is used for stacked file operations on underlying files. Operations on files with "fake" path must not generate fsnotify events with path data, because those events have already been generated at overlayfs layer and because the reported event->fd for fanotify marks on underlying inode/filesystem will have the wrong path (the overlayfs path).
Link: https://lore.kernel.org/linux-fsdevel/20190423065024.12695-1-jencce.kernel@g... Reported-by: Murphy Zhou jencce.kernel@gmail.com Fixes: d1d04ef8572b ("ovl: stack file ops") Signed-off-by: Amir Goldstein amir73il@gmail.com Signed-off-by: Miklos Szeredi mszeredi@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/overlayfs/file.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index 0c810f20f778..2c993937b784 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -29,10 +29,11 @@ static struct file *ovl_open_realfile(const struct file *file, struct inode *inode = file_inode(file); struct file *realfile; const struct cred *old_cred; + int flags = file->f_flags | O_NOATIME | FMODE_NONOTIFY;
old_cred = ovl_override_creds(inode->i_sb); - realfile = open_with_fake_path(&file->f_path, file->f_flags | O_NOATIME, - realinode, current_cred()); + realfile = open_with_fake_path(&file->f_path, flags, realinode, + current_cred()); revert_creds(old_cred);
pr_debug("open(%p[%pD2/%c], 0%o) -> (%p, 0%o)\n", @@ -50,7 +51,7 @@ static int ovl_change_flags(struct file *file, unsigned int flags) int err;
/* No atime modificaton on underlying */ - flags |= O_NOATIME; + flags |= O_NOATIME | FMODE_NONOTIFY;
/* If some flag changed that cannot be changed then something's amiss */ if (WARN_ON((file->f_flags ^ flags) & ~OVL_SETFL_MASK))