Problem was that prog and map inodes in bpf fs did not
implement a dummy file open operation that would return an
error. The patch in do_dentry_open() checks whether f_ops
are present and if not bails out with an error. While this
may be fine, we really shouldn't be throwing a warning
though. Thus follow the model similar to bad_file_ops and
reject the request unconditionally with -EIO.
Fixes: b2197755b263 ("bpf: add support for persistent maps/progs") Reported-by: syzbot+2e7fcab0f56fdbb330b8@syzkaller.appspotmail.com Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org>