From b25b343db0526669947a427e9a31bac91d29bb06 Mon Sep 17 00:00:00 2001
From: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Date: Fri, 2 Apr 2021 10:40:19 -0700
Subject: [PATCH] net: broadcom: bcm4908enet: Fix a double free in
bcm4908_enet_dma_alloc
In bcm4908_enet_dma_alloc, if callee bcm4908_dma_alloc_buf_descs() failed,
it will free the ring->cpu_addr by dma_free_coherent() and return error.
Then bcm4908_enet_dma_free() will be called, and free the same cpu_addr
by dma_free_coherent() again.
My patch set ring->cpu_addr to NULL after it is freed in
bcm4908_dma_alloc_buf_descs() to avoid the double free.
Fixes: 4feffeadbcb2e ("net: broadcom: bcm4908enet: add BCM4908 controller driver")
Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/ethernet/broadcom/bcm4908_enet.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/net/ethernet/broadcom/bcm4908_enet.c b/drivers/net/ethernet/broadcom/bcm4908_enet.c
index 98cf82dea3e4..65981931a798 100644
--- a/drivers/net/ethernet/broadcom/bcm4908_enet.c
+++ b/drivers/net/ethernet/broadcom/bcm4908_enet.c
@@ -172,6 +172,7 @@ static int bcm4908_dma_alloc_buf_descs(struct bcm4908_enet *enet,
err_free_buf_descs:
dma_free_coherent(dev, size, ring->cpu_addr, ring->dma_addr);
+ ring->cpu_addr = NULL;
return -ENOMEM;
}