From 1d2499b0860024c7cd973a8dee375105ffd34156 Mon Sep 17 00:00:00 2001 From: Saeed Mahameed Date: Tue, 19 Mar 2019 01:05:41 -0700 Subject: [PATCH] net/mlx5: FPGA, tls, idr remove on flow delete [ Upstream commit df3a8344d404a810b4aadbf19b08c8232fbaa715 ] Flow is kfreed on mlx5_fpga_tls_del_flow but kept in the idr data structure, this is risky and can cause use-after-free, since the idr_remove is delayed until tls_send_teardown_cmd completion. Instead of delaying idr_remove, in this patch we do it on mlx5_fpga_tls_del_flow, before actually kfree(flow). Added synchronize_rcu before kfree(flow) Fixes: ab412e1dd7db ("net/mlx5: Accel, add TLS rx offload routines") Signed-off-by: Saeed Mahameed Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c | 43 ++++++++-------------- 1 file changed, 15 insertions(+), 28 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c b/drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c index 08aa726..22a2ef1 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/fpga/tls.c @@ -148,14 +148,16 @@ static int mlx5_fpga_tls_alloc_swid(struct idr *idr, spinlock_t *idr_spinlock, return ret; } -static void mlx5_fpga_tls_release_swid(struct idr *idr, - spinlock_t *idr_spinlock, u32 swid) +static void *mlx5_fpga_tls_release_swid(struct idr *idr, + spinlock_t *idr_spinlock, u32 swid) { unsigned long flags; + void *ptr; spin_lock_irqsave(idr_spinlock, flags); - idr_remove(idr, swid); + ptr = idr_remove(idr, swid); spin_unlock_irqrestore(idr_spinlock, flags); + return ptr; } static void mlx_tls_kfree_complete(struct mlx5_fpga_conn *conn, @@ -165,20 +167,12 @@ static void mlx_tls_kfree_complete(struct mlx5_fpga_conn *conn, kfree(buf); } -struct mlx5_teardown_stream_context { - struct mlx5_fpga_tls_command_context cmd; - u32 swid; -}; - static void mlx5_fpga_tls_teardown_completion(struct mlx5_fpga_conn *conn, struct mlx5_fpga_device *fdev, struct mlx5_fpga_tls_command_context *cmd, struct mlx5_fpga_dma_buf *resp) { - struct mlx5_teardown_stream_context *ctx = - container_of(cmd, struct mlx5_teardown_stream_context, cmd); - if (resp) { u32 syndrome = MLX5_GET(tls_resp, resp->sg[0].data, syndrome); @@ -186,14 +180,6 @@ mlx5_fpga_tls_teardown_completion(struct mlx5_fpga_conn *conn, mlx5_fpga_err(fdev, "Teardown stream failed with syndrome = %d", syndrome); - else if (MLX5_GET(tls_cmd, cmd->buf.sg[0].data, direction_sx)) - mlx5_fpga_tls_release_swid(&fdev->tls->tx_idr, - &fdev->tls->tx_idr_spinlock, - ctx->swid); - else - mlx5_fpga_tls_release_swid(&fdev->tls->rx_idr, - &fdev->tls->rx_idr_spinlock, - ctx->swid); } mlx5_fpga_tls_put_command_ctx(cmd); } @@ -253,7 +239,7 @@ int mlx5_fpga_tls_resync_rx(struct mlx5_core_dev *mdev, u32 handle, u32 seq, static void mlx5_fpga_tls_send_teardown_cmd(struct mlx5_core_dev *mdev, void *flow, u32 swid, gfp_t flags) { - struct mlx5_teardown_stream_context *ctx; + struct mlx5_fpga_tls_command_context *ctx; struct mlx5_fpga_dma_buf *buf; void *cmd; @@ -261,7 +247,7 @@ static void mlx5_fpga_tls_send_teardown_cmd(struct mlx5_core_dev *mdev, if (!ctx) return; - buf = &ctx->cmd.buf; + buf = &ctx->buf; cmd = (ctx + 1); MLX5_SET(tls_cmd, cmd, command_type, CMD_TEARDOWN_STREAM); MLX5_SET(tls_cmd, cmd, swid, swid); @@ -272,8 +258,7 @@ static void mlx5_fpga_tls_send_teardown_cmd(struct mlx5_core_dev *mdev, buf->sg[0].data = cmd; buf->sg[0].size = MLX5_TLS_COMMAND_SIZE; - ctx->swid = swid; - mlx5_fpga_tls_cmd_send(mdev->fpga, &ctx->cmd, + mlx5_fpga_tls_cmd_send(mdev->fpga, ctx, mlx5_fpga_tls_teardown_completion); } @@ -283,13 +268,14 @@ void mlx5_fpga_tls_del_flow(struct mlx5_core_dev *mdev, u32 swid, struct mlx5_fpga_tls *tls = mdev->fpga->tls; void *flow; - rcu_read_lock(); if (direction_sx) - flow = idr_find(&tls->tx_idr, swid); + flow = mlx5_fpga_tls_release_swid(&tls->tx_idr, + &tls->tx_idr_spinlock, + swid); else - flow = idr_find(&tls->rx_idr, swid); - - rcu_read_unlock(); + flow = mlx5_fpga_tls_release_swid(&tls->rx_idr, + &tls->rx_idr_spinlock, + swid); if (!flow) { mlx5_fpga_err(mdev->fpga, "No flow information for swid %u\n", @@ -297,6 +283,7 @@ void mlx5_fpga_tls_del_flow(struct mlx5_core_dev *mdev, u32 swid, return; } + synchronize_rcu(); /* before kfree(flow) */ mlx5_fpga_tls_send_teardown_cmd(mdev, flow, swid, flags); } -- 2.7.4