From 64d2c22a4cdd3ce752ca700964a6120049d78aed Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Mon, 22 Jul 2013 11:02:01 +0300 Subject: [PATCH] mlx5: use after free in mlx5_cmd_comp_handler() We can't dereference "ent" after passing it to free_cmd(). Signed-off-by: Dan Carpenter Signed-off-by: David S. Miller --- drivers/net/ethernet/mellanox/mlx5/core/cmd.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c index 205753a04cfc..40374063c01e 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c @@ -1113,7 +1113,13 @@ void mlx5_cmd_comp_handler(struct mlx5_core_dev *dev, unsigned long vector) for (i = 0; i < (1 << cmd->log_sz); i++) { if (test_bit(i, &vector)) { + struct semaphore *sem; + ent = cmd->ent_arr[i]; + if (ent->page_queue) + sem = &cmd->pages_sem; + else + sem = &cmd->sem; ktime_get_ts(&ent->ts2); memcpy(ent->out->first.data, ent->lay->out, sizeof(ent->lay->out)); dump_command(dev, ent, 0); @@ -1136,10 +1142,7 @@ void mlx5_cmd_comp_handler(struct mlx5_core_dev *dev, unsigned long vector) } else { complete(&ent->done); } - if (ent->page_queue) - up(&cmd->pages_sem); - else - up(&cmd->sem); + up(sem); } } } -- 2.20.1