openwrt/target/linux/layerscape/patches-5.4/701-net-0111-sdk_qbman-Avoid-variable-length-array-in-USDPAA.patch

From 0ad840e46732e95df274a84b042dcb210be9f946 Mon Sep 17 00:00:00 2001
From: Roy Pledge <roy.pledge@nxp.com>
Date: Thu, 28 Mar 2019 09:56:35 -0400
Subject: [PATCH] sdk_qbman: Avoid variable length array in USDPAA

As of Linux 5.0 variable length arrays on the stack are no
longer allowed. Change to a dynamic array and create a common
exit point in the function for cleanup.

Signed-off-by: Roy Pledge <roy.pledge@nxp.com>
---
 drivers/staging/fsl_qbman/fsl_usdpaa.c | 36 +++++++++++++++++-----------------
 1 file changed, 18 insertions(+), 18 deletions(-)

--- a/drivers/staging/fsl_qbman/fsl_usdpaa.c
+++ b/drivers/staging/fsl_qbman/fsl_usdpaa.c
@@ -559,6 +559,7 @@ static bool check_portal_channel(void *c
 
 static int usdpaa_release(struct inode *inode, struct file *filp)
 {
+	int err = 0;
 	struct ctx *ctx = filp->private_data;
 	struct mem_mapping *map, *tmpmap;
 	struct portal_mapping *portal, *tmpportal;
@@ -569,9 +570,14 @@ static int usdpaa_release(struct inode *
 	struct qm_portal_config *qm_alloced_portal = NULL;
 	struct bm_portal_config *bm_alloced_portal = NULL;
 
-	struct qm_portal *portal_array[qman_portal_max];
+	struct qm_portal **portal_array;
 	int portal_count = 0;
 
+	portal_array = kmalloc_array(qman_portal_max,
+				     sizeof(struct qm_portal *), GFP_KERNEL);
+	if (!portal_array)
+		return -ENOMEM;
+
 	/* Ensure the release operation cannot be migrated to another
 	   CPU as CPU specific variables may be needed during cleanup */
 #ifdef CONFIG_PREEMPT_RT_FULL
@@ -612,18 +618,14 @@ static int usdpaa_release(struct inode *
 		qm_alloced_portal = qm_get_unused_portal();
 		if (!qm_alloced_portal) {
 			pr_crit("No QMan portal avalaible for cleanup\n");
-#ifdef CONFIG_PREEMPT_RT_FULL
-			migrate_enable();
-#endif
-			return -1;
+			err = -1;
+			goto done;
 		}
 		qm_cleanup_portal = kmalloc(sizeof(struct qm_portal),
 					    GFP_KERNEL);
 		if (!qm_cleanup_portal) {
-#ifdef CONFIG_PREEMPT_RT_FULL
-			migrate_enable();
-#endif
-			return -ENOMEM;
+			err = -ENOMEM;
+			goto done;
 		}
 		init_qm_portal(qm_alloced_portal, qm_cleanup_portal);
 		portal_array[portal_count] = qm_cleanup_portal;
@@ -633,18 +635,14 @@ static int usdpaa_release(struct inode *
 		bm_alloced_portal = bm_get_unused_portal();
 		if (!bm_alloced_portal) {
 			pr_crit("No BMan portal avalaible for cleanup\n");
-#ifdef CONFIG_PREEMPT_RT_FULL
-			migrate_enable();
-#endif
-			return -1;
+			err = -1;
+			goto done;
 		}
 		bm_cleanup_portal = kmalloc(sizeof(struct bm_portal),
 					    GFP_KERNEL);
 		if (!bm_cleanup_portal) {
-#ifdef CONFIG_PREEMPT_RT_FULL
-			migrate_enable();
-#endif
-			return -ENOMEM;
+			err = -ENOMEM;
+			goto done;
 		}
 		init_bm_portal(bm_alloced_portal, bm_cleanup_portal);
 	}
@@ -721,10 +719,12 @@ static int usdpaa_release(struct inode *
 	}
 
 	kfree(ctx);
+done:
 #ifdef CONFIG_PREEMPT_RT_FULL
 	migrate_enable();
 #endif
-	return 0;
+	kfree(portal_array);
+	return err;
 }
 
 static int check_mmap_dma(struct ctx *ctx, struct vm_area_struct *vma,