From f74c8696f14149d5e43cc28b015326a759c48f00 Mon Sep 17 00:00:00 2001 From: Guangshuo Li Date: Tue, 5 May 2026 23:02:56 +0800 Subject: [PATCH] uio: uio_pci_generic_sva: fix double free of devm_kzalloc() memory uio_pci_sva allocates struct uio_pci_sva_dev with devm_kzalloc() in probe(), but then calls kfree(udev) both on the probe() error path (label out_free) and again in remove(). Because devm_kzalloc() allocations are devres-managed and are freed automatically when the device is detached (including after a failing probe() and during driver unbind), the explicit kfree() can lead to a double free. If probe() fails after devm_kzalloc(), the error path frees udev and devres cleanup will free it again when the core unwinds the partially bound device. On normal driver removal, remove() frees udev and devres will free it again when the device is detached. This issue was identified by a static analysis tool I developed and confirmed by manual review. Fix by removing the manual kfree() calls and dropping the now-unused label. Fixes: 3397c3cd859a2 ("uio: Add SVA support for PCI devices via uio_pci_generic_sva.c") Cc: stable Signed-off-by: Guangshuo Li Link: https://patch.msgid.link/20260505150256.614071-1-lgs201920130244@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/uio/uio_pci_generic_sva.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/drivers/uio/uio_pci_generic_sva.c b/drivers/uio/uio_pci_generic_sva.c index 4a46acd994a8..d05ef77f7e32 100644 --- a/drivers/uio/uio_pci_generic_sva.c +++ b/drivers/uio/uio_pci_generic_sva.c @@ -129,15 +129,13 @@ static int probe(struct pci_dev *pdev, const struct pci_device_id *id) ret = devm_uio_register_device(&pdev->dev, &udev->info); if (ret) { dev_err(&pdev->dev, "Failed to register uio device\n"); - goto out_free; + goto out_disable; } pci_set_drvdata(pdev, udev); return 0; -out_free: - kfree(udev); out_disable: pci_disable_device(pdev); @@ -146,11 +144,8 @@ static int probe(struct pci_dev *pdev, const struct pci_device_id *id) static void remove(struct pci_dev *pdev) { - struct uio_pci_sva_dev *udev = pci_get_drvdata(pdev); - pci_release_regions(pdev); pci_disable_device(pdev); - kfree(udev); } static ssize_t pasid_show(struct device *dev,