Commit b350c15a authored May 04, 2020 by Tariq Toukan Committed by Greg Kroah-Hartman May 14, 2020

net/mlx4_core: Fix use of ENOSPC around mlx4_counter_alloc()



[ Upstream commit 40e473071dbad04316ddc3613c3a3d1c75458299 ]

When ENOSPC is set the idx is still valid and gets set to the global
MLX4_SINK_COUNTER_INDEX.  However gcc's static analysis cannot tell that
ENOSPC is impossible from mlx4_cmd_imm() and gives this warning:

drivers/net/ethernet/mellanox/mlx4/main.c:2552:28: warning: 'idx' may be
used uninitialized in this function [-Wmaybe-uninitialized]
 2552 |    priv->def_counter[port] = idx;

Also, when ENOSPC is returned mlx4_allocate_default_counters should not
fail.

Fixes: 6de5f7f6 ("net/mlx4_core: Allocate default counter per port")
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 0899ff04

drivers/net/ethernet/mellanox/mlx4/main.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -2539,6 +2539,7 @@ static int mlx4_allocate_default_counters(struct mlx4_dev *dev)

		if (!err \|\| err == -ENOSPC) {
		priv->def_counter[port] = idx;
		err = 0;
		} else if (err == -ENOENT) {
		err = 0;
		continue;
		@@ -2589,7 +2590,8 @@ int mlx4_counter_alloc(struct mlx4_dev dev, u32 idx, u8 usage)
		MLX4_CMD_TIME_CLASS_A, MLX4_CMD_WRAPPED);
		if (!err)
		*idx = get_param_l(&out_param);

		if (WARN_ON(err == -ENOSPC))
		err = -EINVAL;
		return err;
		}
		return __mlx4_counter_alloc(dev, idx);