2018-07-06 12:46:46

by Arnd Bergmann

Subject: [PATCH net-next] mlxsw: spectrum_router: avoid uninitialized variable access

When CONFIG_BRIDGE_VLAN_FILTERING is disabled, gcc correctly points out
that the 'vid' variable is uninitialized whenever br_vlan_get_pvid
returns an error:

drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c: In function 'mlxsw_sp_rif_vlan_fid_get':
drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:6881:6: error: 'vid' may be used uninitialized in this function [-Werror=maybe-uninitialized]

This changes the condition check to always return -EINVAL here,
which I guess is what the author intended here.

Fixes: e6f1960ae6c7 ("mlxsw: spectrum_router: Allocate FID according to PVID")
Signed-off-by: Arnd Bergmann <[email protected]>
---
drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
index 071428227b91..60c352ddd6fd 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
@@ -6878,11 +6878,9 @@ mlxsw_sp_rif_vlan_fid_get(struct mlxsw_sp_rif *rif,
vid = vlan_dev_vlan_id(rif->dev);
} else {
err = br_vlan_get_pvid(rif->dev, &vid);
- if (!vid)
- err = -EINVAL;
- if (err) {
+ if (err < 0 || !vid) {
NL_SET_ERR_MSG_MOD(extack, "Couldn't determine bridge PVID");
- return ERR_PTR(err);
+ return ERR_PTR(-EINVAL);
}
}

--
2.9.0

2018-07-06 13:19:41

by Ido Schimmel

Subject: Re: [PATCH net-next] mlxsw: spectrum_router: avoid uninitialized variable access

On Fri, Jul 06, 2018 at 02:44:45PM +0200, Arnd Bergmann wrote:
> When CONFIG_BRIDGE_VLAN_FILTERING is disabled, gcc correctly points out
> that the 'vid' variable is uninitialized whenever br_vlan_get_pvid
> returns an error:
>
> drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c: In function 'mlxsw_sp_rif_vlan_fid_get':
> drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:6881:6: error: 'vid' may be used uninitialized in this function [-Werror=maybe-uninitialized]
>
> This changes the condition check to always return -EINVAL here,
> which I guess is what the author intended here.
>
> Fixes: e6f1960ae6c7 ("mlxsw: spectrum_router: Allocate FID according to PVID")
> Signed-off-by: Arnd Bergmann <[email protected]>

Reviewed-by: Ido Schimmel <[email protected]>

Thanks!

2018-07-07 11:09:01

by David Miller

Subject: Re: [PATCH net-next] mlxsw: spectrum_router: avoid uninitialized variable access

From: Arnd Bergmann <[email protected]>
Date: Fri, 6 Jul 2018 14:44:45 +0200

> When CONFIG_BRIDGE_VLAN_FILTERING is disabled, gcc correctly points out
> that the 'vid' variable is uninitialized whenever br_vlan_get_pvid
> returns an error:
>
> drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c: In function 'mlxsw_sp_rif_vlan_fid_get':
> drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:6881:6: error: 'vid' may be used uninitialized in this function [-Werror=maybe-uninitialized]
>
> This changes the condition check to always return -EINVAL here,
> which I guess is what the author intended here.
>
> Fixes: e6f1960ae6c7 ("mlxsw: spectrum_router: Allocate FID according to PVID")
> Signed-off-by: Arnd Bergmann <[email protected]>

Applied.