diff options
| author | Stanislav Fomichev <sdf@google.com> | 2024-04-26 16:16:18 -0700 |
|---|---|---|
| committer | Martin KaFai Lau <martin.lau@kernel.org> | 2024-04-30 10:43:37 -0700 |
| commit | 543576ec15b17c0c93301ac8297333c7b6e84ac7 (patch) | |
| tree | 9ee27656356c0a9d30f53a807ef9f42a931f5c00 | |
| parent | b867247555c4181bf84eb10b72b176862c29112d (diff) | |
| download | bpf-543576ec15b17c0c93301ac8297333c7b6e84ac7.tar.gz | |
bpf: Add BPF_PROG_TYPE_CGROUP_SKB attach type enforcement in BPF_LINK_CREATE
bpf_prog_attach uses attach_type_to_prog_type to enforce proper
attach type for BPF_PROG_TYPE_CGROUP_SKB. link_create uses
bpf_prog_get and relies on bpf_prog_attach_check_attach_type
to properly verify prog_type <> attach_type association.
Add missing attach_type enforcement for the link_create case.
Otherwise, it's currently possible to attach cgroup_skb prog
types to other cgroup hooks.
Fixes: af6eea57437a ("bpf: Implement bpf_link-based cgroup BPF program attachment")
Link: https://lore.kernel.org/bpf/0000000000004792a90615a1dde0@google.com/
Reported-by: syzbot+838346b979830606c854@syzkaller.appspotmail.com
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240426231621.2716876-2-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
| -rw-r--r-- | kernel/bpf/syscall.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index c287925471f68e..cb61d8880dbe03 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -3985,6 +3985,11 @@ static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, * check permissions at attach time. */ return -EPERM; + + ptype = attach_type_to_prog_type(attach_type); + if (prog->type != ptype) + return -EINVAL; + return prog->enforce_expected_attach_type && prog->expected_attach_type != attach_type ? -EINVAL : 0; |