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| author | Jesper Dangaard Brouer <brouer@redhat.com> | 2018-08-08 23:00:45 +0200 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2018-08-09 21:50:44 +0200 |
| commit | 1bf9116d0866a649104a5dfa008c302ad54d1e02 (patch) | |
| tree | e758a1cbc47dcaff5e9c13ee2b336dd48994c881 /kernel/bpf | |
| parent | samples/bpf: xdp_redirect_cpu adjustment to reproduce teardown race easier (diff) | |
| download | linux-1bf9116d0866a649104a5dfa008c302ad54d1e02.tar.xz linux-1bf9116d0866a649104a5dfa008c302ad54d1e02.zip | |
xdp: fix bug in devmap teardown code path
Like cpumap teardown, the devmap teardown code also flush remaining
xdp_frames, via bq_xmit_all() in case map entry is removed. The code
can call xdp_return_frame_rx_napi, from the the wrong context, in-case
ndo_xdp_xmit() fails.
Fixes: 389ab7f01af9 ("xdp: introduce xdp_return_frame_rx_napi")
Fixes: 735fc4054b3a ("xdp: change ndo_xdp_xmit API to support bulking")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Diffstat (limited to 'kernel/bpf')
| -rw-r--r-- | kernel/bpf/devmap.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index d361fc1e3bf3..750d45edae79 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -217,7 +217,8 @@ void __dev_map_insert_ctx(struct bpf_map *map, u32 bit) } static int bq_xmit_all(struct bpf_dtab_netdev *obj, - struct xdp_bulk_queue *bq, u32 flags) + struct xdp_bulk_queue *bq, u32 flags, + bool in_napi_ctx) { struct net_device *dev = obj->dev; int sent = 0, drops = 0, err = 0; @@ -254,7 +255,10 @@ error: struct xdp_frame *xdpf = bq->q[i]; /* RX path under NAPI protection, can return frames faster */ - xdp_return_frame_rx_napi(xdpf); + if (likely(in_napi_ctx)) + xdp_return_frame_rx_napi(xdpf); + else + xdp_return_frame(xdpf); drops++; } goto out; @@ -286,7 +290,7 @@ void __dev_map_flush(struct bpf_map *map) __clear_bit(bit, bitmap); bq = this_cpu_ptr(dev->bulkq); - bq_xmit_all(dev, bq, XDP_XMIT_FLUSH); + bq_xmit_all(dev, bq, XDP_XMIT_FLUSH, true); } } @@ -316,7 +320,7 @@ static int bq_enqueue(struct bpf_dtab_netdev *obj, struct xdp_frame *xdpf, struct xdp_bulk_queue *bq = this_cpu_ptr(obj->bulkq); if (unlikely(bq->count == DEV_MAP_BULK_SIZE)) - bq_xmit_all(obj, bq, 0); + bq_xmit_all(obj, bq, 0, true); /* Ingress dev_rx will be the same for all xdp_frame's in * bulk_queue, because bq stored per-CPU and must be flushed @@ -385,7 +389,7 @@ static void dev_map_flush_old(struct bpf_dtab_netdev *dev) __clear_bit(dev->bit, bitmap); bq = per_cpu_ptr(dev->bulkq, cpu); - bq_xmit_all(dev, bq, XDP_XMIT_FLUSH); + bq_xmit_all(dev, bq, XDP_XMIT_FLUSH, false); } } } |