From 777682e59840e24e6c5672197e6ffbcf4bff823b Mon Sep 17 00:00:00 2001
From: Dave Ertman <david.m.ertman@intel.com>
Date: Mon, 4 Oct 2021 05:15:25 -0700
Subject: [PATCH] ice: Avoid crash from unnecessary IDA free
Git-commit: 73e30a62b19b9fbb4e6a3465c59da186630d5f2e
Patch-mainline: v5.15-rc7
References: stable-5.14.15

[ Upstream commit 73e30a62b19b9fbb4e6a3465c59da186630d5f2e ]

In the remove path, there is an attempt to free the aux_idx IDA whether
it was allocated or not.  This can potentially cause a crash when
unloading the driver on systems that do not initialize support for RDMA.
But, this free cannot be gated by the status bit for RDMA, since it is
allocated if the driver detects support for RDMA at probe time, but the
driver can enter into a state where RDMA is not supported after the IDA
has been allocated at probe time and this would lead to a memory leak.

Initialize aux_idx to an invalid value and check for a valid value when
unloading to determine if an IDA free is necessary.

Fixes: d25a0fc41c1f9 ("ice: Initialize RDMA support")
Reported-by: Jun Miao <jun.miao@windriver.com>
Signed-off-by: Dave Ertman <david.m.ertman@intel.com>
Tested-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/ethernet/intel/ice/ice_main.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index a8bd512d5b45..3a47b03310f3 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -4224,6 +4224,9 @@ ice_probe(struct pci_dev *pdev, const struct pci_device_id __always_unused *ent)
 	if (!pf)
 		return -ENOMEM;
 
+	/* initialize Auxiliary index to invalid value */
+	pf->aux_idx = -1;
+
 	/* set up for high or low DMA */
 	err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
 	if (err)
@@ -4615,7 +4618,8 @@ static void ice_remove(struct pci_dev *pdev)
 
 	ice_aq_cancel_waiting_tasks(pf);
 	ice_unplug_aux_dev(pf);
-	ida_free(&ice_aux_ida, pf->aux_idx);
+	if (pf->aux_idx >= 0)
+		ida_free(&ice_aux_ida, pf->aux_idx);
 	set_bit(ICE_DOWN, pf->state);
 
 	mutex_destroy(&(&pf->hw)->fdir_fltr_lock);
-- 
2.26.2