RE: [PATCH] EDAC/sb_edac: Fix pci_vtd reference leak in broadwell_mci_bind_devs()

[Leo Zhuo]

> From: Wentao Liang <vulab@xxxxxxxxxxx>
> [...]
> Subject: [PATCH] EDAC/sb_edac: Fix pci_vtd reference leak in
> broadwell_mci_bind_devs()
> 
> 
> In broadwell_mci_bind_devs(), a reference to the VT-d device is taken with
> pci_get_device() and stored in pvt->info.pci_vtd.  If one of the required devices is
> missing, the function returns -ENODEV without putting that reference, and the
> caller frees the mem_ctl_info along with its private data, leaking the reference.
> 
> Put the device reference before returning on the error path.
> 
> Fixes: 1f39581a9a7a ("sb_edac: Add support for Broadwell-DE processor")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Wentao Liang <vulab@xxxxxxxxxxx>
> ---
>  drivers/edac/sb_edac.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/edac/sb_edac.c b/drivers/edac/sb_edac.c index
> 5075c703e19e..7ec29e50f5d7 100644
> --- a/drivers/edac/sb_edac.c
> +++ b/drivers/edac/sb_edac.c
> @@ -2929,6 +2929,8 @@ static int broadwell_mci_bind_devs(struct mem_ctl_info
> *mci,
>         return 0;
> 
>  enodev:
> +       pci_dev_put(pvt->info.pci_vtd);
> +       pvt->info.pci_vtd = NULL;

See comments: 
https://lore.kernel.org/all/CY8PR12MB72909C59B4374AB917E1D99DD1B92@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/