On Fri, Mar 26, 2021 at 1:14 PM Song Liu <song@xxxxxxxxxx> wrote: > > On Fri, Mar 26, 2021 at 9:07 AM Lorenz Bauer <lmb@xxxxxxxxxxxxxx> wrote: > > > > As for bpf_link, refuse creating a non-O_RDWR fd. Since program fds > > currently don't allow modifications this is a precaution, not a > > straight up bug fix. > > > > Signed-off-by: Lorenz Bauer <lmb@xxxxxxxxxxxxxx> > > --- > > kernel/bpf/inode.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c > > index dc56237d6960..d2de2abec35b 100644 > > --- a/kernel/bpf/inode.c > > +++ b/kernel/bpf/inode.c > > @@ -543,7 +543,7 @@ int bpf_obj_get_user(const char __user *pathname, int flags) > > return PTR_ERR(raw); > > For both patches, shall we do the check before bpf_obj_do_get(), which is a few > lines above? Map does use f_flags, so we need to let them through. Or did you mean to do a (type != BPF_TYPE_MAP && f_flags != O_RDWR) check? Either way is fine with me, so: Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx> > > Thanks, > Song > > > > > if (type == BPF_TYPE_PROG) > > - ret = bpf_prog_new_fd(raw); > > + ret = (f_flags != O_RDWR) ? -EINVAL : bpf_prog_new_fd(raw); > > else if (type == BPF_TYPE_MAP) > > ret = bpf_map_new_fd(raw, f_flags); > > else if (type == BPF_TYPE_LINK) > > -- > > 2.27.0 > >
