Currently lo_flush() is written in such a way that it expects to receive a FLUSH requests on a regular file (and not directories). For example, we call lo_fi_fd() which searches lo->fd_map. If we open directories using opendir(), we keep don't keep track of these in lo->fd_map instead we keep them in lo->dir_map. So we expect lo_flush() to be called on regular files only.
Even linux fuse client calls FLUSH only for regular files and not directories. So put a check for filetype and return EBADF if lo_flush() is called on a non-regular file. Reported-by: Laszlo Ersek <ler...@redhat.com> Signed-off-by: Vivek Goyal <vgo...@redhat.com> --- tools/virtiofsd/passthrough_ll.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c index 8ba79f503a..48a109d3f6 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -1968,7 +1968,7 @@ static void lo_flush(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi) struct lo_data *lo = lo_data(req); inode = lo_inode(req, ino); - if (!inode) { + if (!inode || !S_ISREG(inode->filetype)) { fuse_reply_err(req, EBADF); return; } -- 2.25.4