From 37df9f3fedb6aeaff5564145e8162aab912c9284 Mon Sep 17 00:00:00 2001 From: Lv Yunlong Date: Wed, 24 Mar 2021 03:37:24 -0700 Subject: [PATCH] video: hyperv_fb: Fix a double free in hvfb_probe Function hvfb_probe() calls hvfb_getmem(), expecting upon return that info->apertures is either NULL or points to memory that should be freed by framebuffer_release(). But hvfb_getmem() is freeing the memory and leaving the pointer non-NULL, resulting in a double free if an error occurs or later if hvfb_remove() is called. Fix this by removing all kfree(info->apertures) calls in hvfb_getmem(). This will allow framebuffer_release() to free the memory, which follows the pattern of other fbdev drivers. Fixes: 3a6fb6c4255c ("video: hyperv: hyperv_fb: Use physical memory for fb on HyperV Gen 1 VMs.") Signed-off-by: Lv Yunlong Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20210324103724.4189-1-lyl2019@mail.ustc.edu.cn Signed-off-by: Wei Liu --- drivers/video/fbdev/hyperv_fb.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c index c8b0ae676809..4dc9077dd2ac 100644 --- a/drivers/video/fbdev/hyperv_fb.c +++ b/drivers/video/fbdev/hyperv_fb.c @@ -1031,7 +1031,6 @@ static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info) PCI_DEVICE_ID_HYPERV_VIDEO, NULL); if (!pdev) { pr_err("Unable to find PCI Hyper-V video\n"); - kfree(info->apertures); return -ENODEV; } @@ -1129,7 +1128,6 @@ getmem_done: } else { pci_dev_put(pdev); } - kfree(info->apertures); return 0; @@ -1141,7 +1139,6 @@ err2: err1: if (!gen2vm) pci_dev_put(pdev); - kfree(info->apertures); return -ENOMEM; }