linux-kernel - [PATCH v1] xen/pvcalls: free active map buffer on pvcalls_front_free

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Date:   Tue, 20 Dec 2022 14:50:13 +0000
From:   Oleksii Moisieiev <Oleksii_Moisieiev@...m.com>
To:     "sstabellini@...nel.org" <sstabellini@...nel.org>
CC:     Oleksii Moisieiev <Oleksii_Moisieiev@...m.com>,
        Juergen Gross <jgross@...e.com>,
        Oleksandr Tyshchenko <Oleksandr_Tyshchenko@...m.com>,
        "xen-devel@...ts.xenproject.org" <xen-devel@...ts.xenproject.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: [PATCH v1] xen/pvcalls: free active map buffer on
 pvcalls_front_free_map

Data buffer for active map is allocated in alloc_active_ring and freed
in free_active_ring function, which is used only for the error
cleanup. pvcalls_front_release is calling pvcalls_front_free_map which
ends foreign access for this buffer, but doesn't free allocated pages.
Call free_active_ring to clean all allocated resources.

Signed-off-by: Oleksii Moisieiev <oleksii_moisieiev@...m.com>
---
 drivers/xen/pvcalls-front.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c
index 1826e8e67125..9b569278788a 100644
--- a/drivers/xen/pvcalls-front.c
+++ b/drivers/xen/pvcalls-front.c
@@ -225,6 +225,8 @@ static irqreturn_t pvcalls_front_event_handler(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+static void free_active_ring(struct sock_mapping *map);
+
 static void pvcalls_front_free_map(struct pvcalls_bedata *bedata,
 				   struct sock_mapping *map)
 {
@@ -240,7 +242,7 @@ static void pvcalls_front_free_map(struct pvcalls_bedata *bedata,
 	for (i = 0; i < (1 << PVCALLS_RING_ORDER); i++)
 		gnttab_end_foreign_access(map->active.ring->ref[i], NULL);
 	gnttab_end_foreign_access(map->active.ref, NULL);
-	free_page((unsigned long)map->active.ring);
+	free_active_ring(map);
 
 	kfree(map);
 }
-- 
2.25.1