This is a note to let you know that I've just added the patch titled video: hyperv_fb: Fix a double free in hvfb_probe to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: video-hyperv_fb-fix-a-double-free-in-hvfb_probe.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit a58c78691d4cf5881cabe813708b7bde99415da8 Author: Lv Yunlong <lyl2019@xxxxxxxxxxxxxxxx> Date: Wed Mar 24 03:37:24 2021 -0700 video: hyperv_fb: Fix a double free in hvfb_probe [ Upstream commit 37df9f3fedb6aeaff5564145e8162aab912c9284 ] 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 <lyl2019@xxxxxxxxxxxxxxxx> Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210324103724.4189-1-lyl2019@xxxxxxxxxxxxxxxx Signed-off-by: Wei Liu <wei.liu@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> 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; }