4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jiri Pirko <jiri@xxxxxxxxxxxx>
[ Upstream commit 0f2d2b2736b08dafa3bde31d048750fbc8df3a31 ]
Since mlxsw_sp_fib_create() and mlxsw_sp_mr_table_create()
use ERR_PTR macro to propagate int err through return of a pointer,
the return value is not NULL in case of failure. So if one
of the calls fails, one of vr->fib4, vr->fib6 or vr->mr4_table
is not NULL and mlxsw_sp_vr_is_used wrongly assumes
that vr is in use which leads to crash like following one:
[ 1293.949291] BUG: unable to handle kernel NULL pointer dereference at 00000000000006c9
[ 1293.952729] IP: mlxsw_sp_mr_table_flush+0x15/0x70 [mlxsw_spectrum]
Fix this by using local variables to hold the pointers and set vr->*
only in case everything went fine.
Fixes: 76610ebbde18 ("mlxsw: spectrum_router: Refactor virtual router handling")
Fixes: a3d9bc506d64 ("mlxsw: spectrum_router: Extend virtual routers with IPv6 support")
Fixes: d42b0965b1d4 ("mlxsw: spectrum_router: Add multicast routes notification handling functionality")
Signed-off-by: Jiri Pirko <jiri@xxxxxxxxxxxx>
Reviewed-by: Ido Schimmel <idosch@xxxxxxxxxxxx>
Signed-off-by: Jiri Pirko <jiri@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c | 19 ++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
@@ -729,26 +729,29 @@ static struct mlxsw_sp_fib *mlxsw_sp_vr_
static struct mlxsw_sp_vr *mlxsw_sp_vr_create(struct mlxsw_sp *mlxsw_sp,
u32 tb_id)
{
+ struct mlxsw_sp_fib *fib4;
+ struct mlxsw_sp_fib *fib6;
struct mlxsw_sp_vr *vr;
int err;
vr = mlxsw_sp_vr_find_unused(mlxsw_sp);
if (!vr)
return ERR_PTR(-EBUSY);
- vr->fib4 = mlxsw_sp_fib_create(vr, MLXSW_SP_L3_PROTO_IPV4);
- if (IS_ERR(vr->fib4))
- return ERR_CAST(vr->fib4);
- vr->fib6 = mlxsw_sp_fib_create(vr, MLXSW_SP_L3_PROTO_IPV6);
- if (IS_ERR(vr->fib6)) {
- err = PTR_ERR(vr->fib6);
+ fib4 = mlxsw_sp_fib_create(vr, MLXSW_SP_L3_PROTO_IPV4);
+ if (IS_ERR(fib4))
+ return ERR_CAST(fib4);
+ fib6 = mlxsw_sp_fib_create(vr, MLXSW_SP_L3_PROTO_IPV6);
+ if (IS_ERR(fib6)) {
+ err = PTR_ERR(fib6);
goto err_fib6_create;
}
+ vr->fib4 = fib4;
+ vr->fib6 = fib6;
vr->tb_id = tb_id;
return vr;
err_fib6_create:
- mlxsw_sp_fib_destroy(vr->fib4);
- vr->fib4 = NULL;
+ mlxsw_sp_fib_destroy(fib4);
return ERR_PTR(err);
}