From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] bpf, mlx4: fix prog refcount in
 mlx4_en_try_alloc_resources error path
Date: Sat, 12 Nov 2016 23:34:09 -0500 (EST)
Message-ID: <20161112.233409.1021924000003441192.davem@davemloft.net>
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From: Daniel Borkmann <daniel@iogearbox.net>
Date: Wed,  9 Nov 2016 22:02:34 +0100

> Commit 67f8b1dcb9ee ("net/mlx4_en: Refactor the XDP forwarding rings
> scheme") added a bug in that the prog's reference count is not dropped
> in the error path when mlx4_en_try_alloc_resources() is failing from
> mlx4_xdp_set().
> 
> We previously took bpf_prog_add(prog, priv->rx_ring_num - 1), that we
> need to release again. Earlier in the call path, dev_change_xdp_fd()
> itself holds a reference to the prog as well (hence the '- 1' in the
> bpf_prog_add()), so a simple atomic_sub() is safe to use here. When
> an error is propagated, then bpf_prog_put() is called eventually from
> dev_change_xdp_fd()
> 
> Fixes: 67f8b1dcb9ee ("net/mlx4_en: Refactor the XDP forwarding rings scheme")
> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Applied, thanks Daniel.