From a2c320d7c725607235185fb7345dfcf40b87a72a Mon Sep 17 00:00:00 2001 From: Hans Petter Selasky Date: Fri, 16 Sep 2016 11:57:48 +0000 Subject: [PATCH] mlx5en: Fix duplicate mbuf free-by-code. When mlx5e_sq_xmit() returns an error code and the mbuf pointer is set, we should not free the mbuf, because the caller will keep the mbuf in the drbr. Make sure the mbuf pointer is correctly set upon function exit. Sponsored by: Mellanox Technologies MFC after: 1 week --- sys/dev/mlx5/mlx5_en/mlx5_en_tx.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/sys/dev/mlx5/mlx5_en/mlx5_en_tx.c b/sys/dev/mlx5/mlx5_en/mlx5_en_tx.c index f83b11eeece..eae3d728dff 100644 --- a/sys/dev/mlx5/mlx5_en/mlx5_en_tx.c +++ b/sys/dev/mlx5/mlx5_en/mlx5_en_tx.c @@ -224,10 +224,8 @@ mlx5e_sq_xmit(struct mlx5e_sq *sq, struct mbuf **mbp) /* Send one multi NOP message instead of many */ mlx5e_send_nop(sq, (pi + 1) * MLX5_SEND_WQEBB_NUM_DS); pi = ((~sq->pc) & sq->wq.sz_m1); - if (pi < (MLX5_SEND_WQE_MAX_WQEBBS - 1)) { - m_freem(mb); + if (pi < (MLX5_SEND_WQE_MAX_WQEBBS - 1)) return (ENOMEM); - } } /* Setup local variables */ @@ -338,10 +336,8 @@ mlx5e_sq_xmit(struct mlx5e_sq *sq, struct mbuf **mbp) mb, segs, &nsegs, BUS_DMA_NOWAIT); } /* Catch errors */ - if (err != 0) { + if (err != 0) goto tx_drop; - } - *mbp = mb; for (x = 0; x != nsegs; x++) { if (segs[x].ds_len == 0) @@ -374,6 +370,7 @@ skip_dma: bus_dmamap_sync(sq->dma_tag, sq->mbuf[pi].dma_map, BUS_DMASYNC_PREWRITE); sq->stats.packets++; + *mbp = NULL; /* safety clear */ return (0); tx_drop: