[PATCH] video/fbdev: Fix a double free in hvfb_probe

[Lv Yunlong]

In function hvfb_probe in hyperv_fb.c, it calls hvfb_getmem(hdev, info)
and return err when info->apertures is freed.

In the error1 label of hvfb_probe, info->apertures will be freed twice
by framebuffer_release(info).

My patch sets info->apertures to NULL after it was freed to avoid
double free.

Signed-off-by: Lv Yunlong <lyl2...@mail.ustc.edu.cn>
---
 drivers/video/fbdev/hyperv_fb.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c
index c8b0ae676809..2fc9b507e73a 100644
--- a/drivers/video/fbdev/hyperv_fb.c
+++ b/drivers/video/fbdev/hyperv_fb.c
@@ -1032,6 +1032,7 @@ static int hvfb_getmem(struct hv_device *hdev, struct 
fb_info *info)
                if (!pdev) {
                        pr_err("Unable to find PCI Hyper-V video\n");
                        kfree(info->apertures);
+                       info->apertures = NULL;
                        return -ENODEV;
                }
 
@@ -1130,6 +1131,7 @@ static int hvfb_getmem(struct hv_device *hdev, struct 
fb_info *info)
                pci_dev_put(pdev);
        }
        kfree(info->apertures);
+       info->apertures = NULL;
 
        return 0;
 
@@ -1142,6 +1144,7 @@ static int hvfb_getmem(struct hv_device *hdev, struct 
fb_info *info)
        if (!gen2vm)
                pci_dev_put(pdev);
        kfree(info->apertures);
+       info->apertures = NULL;
 
        return -ENOMEM;
 }
-- 
2.25.1