From: Ivan Vecera <ivecera@redhat.com>
Date: Fri, 1 Apr 2022 12:40:52 +0200
Subject: ice: Fix incorrect locking in ice_vc_process_vf_msg()
Patch-mainline: v5.18-rc5
Git-commit: aaf461af729b81dbb19ec33abe6da74702b352d2
References: jsc#SLE-18375

Usage of mutex_trylock() in ice_vc_process_vf_msg() is incorrect
because message sent from VF is ignored and never processed.

Use mutex_lock() instead to fix the issue. It is safe because this
mutex is used to prevent races between VF related NDOs and
handlers processing request messages from VF and these handlers
are running in ice_service_task() context. Additionally move this
mutex lock prior ice_vc_is_opcode_allowed() call to avoid potential
races during allowlist access.

Fixes: e6ba5273d4ed ("ice: Fix race conditions between virtchnl handling and VF ndo ops")
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c |   20 +++++++-------------
 1 file changed, 7 insertions(+), 13 deletions(-)

--- a/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c
@@ -4688,13 +4688,6 @@ void ice_vc_process_vf_msg(struct ice_pf
 			err = -EINVAL;
 	}
 
-	if (!ice_vc_is_opcode_allowed(vf, v_opcode)) {
-		ice_vc_send_msg_to_vf(vf, v_opcode,
-				      VIRTCHNL_STATUS_ERR_NOT_SUPPORTED, NULL,
-				      0);
-		return;
-	}
-
 error_handler:
 	if (err) {
 		ice_vc_send_msg_to_vf(vf, v_opcode, VIRTCHNL_STATUS_ERR_PARAM,
@@ -4704,12 +4697,13 @@ error_handler:
 		return;
 	}
 
-	/* VF is being configured in another context that triggers a VFR, so no
-	 * need to process this message
-	 */
-	if (!mutex_trylock(&vf->cfg_lock)) {
-		dev_info(dev, "VF %u is being configured in another context that will trigger a VFR, so there is no need to handle this message\n",
-			 vf->vf_id);
+	mutex_lock(&vf->cfg_lock);
+
+	if (!ice_vc_is_opcode_allowed(vf, v_opcode)) {
+		ice_vc_send_msg_to_vf(vf, v_opcode,
+				      VIRTCHNL_STATUS_ERR_NOT_SUPPORTED, NULL,
+				      0);
+		mutex_unlock(&vf->cfg_lock);
 		return;
 	}