github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-06-02 03:24:19 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

uio: uio_pci_generic_sva: fix double free of devm_kzalloc() memory

Browse Source 
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: 3397c3cd85 ("uio: Add SVA support for PCI devices via uio_pci_generic_sva.c")
Cc: stable <stable@kernel.org>
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
Link: https://patch.msgid.link/20260505150256.614071-1-lgs201920130244@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Guangshuo Li 2026-05-05 23:02:56 +08:00 committed by Greg Kroah-Hartman
parent f6d8fea9e3
commit f74c8696f1
1 changed files with 1 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
drivers/uio/uio_pci_generic_sva.c
View File

@ -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,