diff options
author | Andrii Nakryiko <andriin@fb.com> | 2020-08-11 19:29:23 -0700 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2020-08-12 18:00:49 -0700 |
commit | 068d9d1eba72423e99162aad3586727180715c2a (patch) | |
tree | 5a002b874b1bf8fc3f58ba74b3dd4d5c46bfe70c | |
parent | da7bdfdd23b858e6d97a1e4b461548e23d16977f (diff) |
bpf: Fix XDP FD-based attach/detach logic around XDP_FLAGS_UPDATE_IF_NOEXIST
Enforce XDP_FLAGS_UPDATE_IF_NOEXIST only if new BPF program to be attached is
non-NULL (i.e., we are not detaching a BPF program).
Fixes: d4baa9368a5e ("bpf, xdp: Extract common XDP program attachment logic")
Reported-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20200812022923.1217922-1-andriin@fb.com
-rw-r--r-- | net/core/dev.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 7df6c9617321..b5d1129d8310 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -8913,10 +8913,6 @@ static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack NL_SET_ERR_MSG(extack, "Active program does not match expected"); return -EEXIST; } - if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) { - NL_SET_ERR_MSG(extack, "XDP program already attached"); - return -EBUSY; - } /* put effective new program into new_prog */ if (link) @@ -8927,6 +8923,10 @@ static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack enum bpf_xdp_mode other_mode = mode == XDP_MODE_SKB ? XDP_MODE_DRV : XDP_MODE_SKB; + if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) { + NL_SET_ERR_MSG(extack, "XDP program already attached"); + return -EBUSY; + } if (!offload && dev_xdp_prog(dev, other_mode)) { NL_SET_ERR_MSG(extack, "Native and generic XDP can't be active at the same time"); return -EEXIST; |