Smatch reported:
drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c:73 gp_aux_bus_probe() warn:
missing unwind goto?
In gp_aux_bus_probe(), when the allocation of
aux_bus->aux_device_wrapper[1] fails, it needs to clean up the allocated
resources.
Fix this by revising the return statement to a goto statement.
Fixes: 393fc2f5948f ("misc: microchip: pci1xxxx: load auxiliary bus driver for the PIO function in the multi-function endpoint of pci1xxxx device.")
Signed-off-by: Xinyi Hou <[email protected]>
Reviewed-by: Dongliang Mu <[email protected]>
---
The issue is found by static analysis, and the patch remains untest.
---
drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c b/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c
index 32af2b14ff34..2c64b6b3cd9c 100644
--- a/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c
+++ b/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c
@@ -69,8 +69,10 @@ static int gp_aux_bus_probe(struct pci_dev *pdev, const struct pci_device_id *id
aux_bus->aux_device_wrapper[1] = kzalloc(sizeof(*aux_bus->aux_device_wrapper[1]),
GFP_KERNEL);
- if (!aux_bus->aux_device_wrapper[1])
- return -ENOMEM;
+ if (!aux_bus->aux_device_wrapper[1]) {
+ retval = -ENOMEM;
+ goto err_aux_dev_add_0;
+ }
retval = ida_alloc(&gp_client_ida, GFP_KERNEL);
if (retval < 0)
--
2.25.1
> -----Original Message-----
> From: Xinyi Hou <[email protected]>
> Sent: Sunday, April 9, 2023 6:18 PM
> To: Kumaravel Thiagarajan - I21417
> <[email protected]>; Arnd Bergmann
> <[email protected]>; Greg Kroah-Hartman <[email protected]>
>
> Smatch reported:
>
> drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c:73 gp_aux_bus_probe()
> warn:
> missing unwind goto?
>
> In gp_aux_bus_probe(), when the allocation of aux_bus-
> >aux_device_wrapper[1] fails, it needs to clean up the allocated resources.
>
> Fix this by revising the return statement to a goto statement.
>
> Fixes: 393fc2f5948f ("misc: microchip: pci1xxxx: load auxiliary bus driver for
> the PIO function in the multi-function endpoint of pci1xxxx device.")
> Signed-off-by: Xinyi Hou <[email protected]>
> Reviewed-by: Dongliang Mu <[email protected]>
Reviewed-by: Kumaravel Thiagarajan <[email protected]>
> ---
> The issue is found by static analysis, and the patch remains untest.
> ---
>
> drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c
> b/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c
> index 32af2b14ff34..2c64b6b3cd9c 100644
> --- a/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c
> +++ b/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c
> @@ -69,8 +69,10 @@ static int gp_aux_bus_probe(struct pci_dev *pdev,
> const struct pci_device_id *id
>
> aux_bus->aux_device_wrapper[1] = kzalloc(sizeof(*aux_bus-
> >aux_device_wrapper[1]),
> GFP_KERNEL);
> - if (!aux_bus->aux_device_wrapper[1])
> - return -ENOMEM;
> + if (!aux_bus->aux_device_wrapper[1]) {
> + retval = -ENOMEM;
> + goto err_aux_dev_add_0;
> + }
>
> retval = ida_alloc(&gp_client_ida, GFP_KERNEL);
> if (retval < 0)
> --
> 2.25.1
On Thu, Apr 13, 2023 at 04:43:10AM +0000, [email protected] wrote:
> > -----Original Message-----
> > From: Xinyi Hou <[email protected]>
> > Sent: Sunday, April 9, 2023 6:18 PM
> > To: Kumaravel Thiagarajan - I21417
> > <[email protected]>; Arnd Bergmann
> > <[email protected]>; Greg Kroah-Hartman <[email protected]>
> >
> > Smatch reported:
> >
> > drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c:73 gp_aux_bus_probe()
> > warn:
> > missing unwind goto?
> >
> > In gp_aux_bus_probe(), when the allocation of aux_bus-
> > >aux_device_wrapper[1] fails, it needs to clean up the allocated resources.
> >
> > Fix this by revising the return statement to a goto statement.
> >
> > Fixes: 393fc2f5948f ("misc: microchip: pci1xxxx: load auxiliary bus driver for
> > the PIO function in the multi-function endpoint of pci1xxxx device.")
> > Signed-off-by: Xinyi Hou <[email protected]>
> > Reviewed-by: Dongliang Mu <[email protected]>
> Reviewed-by: Kumaravel Thiagarajan <[email protected]>
> > ---
> > The issue is found by static analysis, and the patch remains untest.
Despite all the reviewers, this patch is incorrect :(
Please test patches, or better yet, restructure the code to not need to
bail out in such a "deep" call path so that errors like this are not an
issue.
thanks,
greg k-h