From: Benjamin Poirier bpoirier@nvidia.com

stable inclusion from stable-v6.6.52 commit 65feee671e37f3b6eda0b6af28f204b5bcf7fa50 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAU9OW CVE: CVE-2024-46857

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

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[ Upstream commit b1d305abef4640af1b4f1b4774d513cd81b10cfc ]

Currently, trying to set the bridge mode attribute when numvfs=0 leads to a crash:

bridge link set dev eth2 hwmode vepa

[ 168.967392] BUG: kernel NULL pointer dereference, address: 0000000000000030 [...] [ 168.969989] RIP: 0010:mlx5_add_flow_rules+0x1f/0x300 [mlx5_core] [...] [ 168.976037] Call Trace: [ 168.976188] <TASK> [ 168.978620] _mlx5_eswitch_set_vepa_locked+0x113/0x230 [mlx5_core] [ 168.979074] mlx5_eswitch_set_vepa+0x7f/0xa0 [mlx5_core] [ 168.979471] rtnl_bridge_setlink+0xe9/0x1f0 [ 168.979714] rtnetlink_rcv_msg+0x159/0x400 [ 168.980451] netlink_rcv_skb+0x54/0x100 [ 168.980675] netlink_unicast+0x241/0x360 [ 168.980918] netlink_sendmsg+0x1f6/0x430 [ 168.981162] ____sys_sendmsg+0x3bb/0x3f0 [ 168.982155] ___sys_sendmsg+0x88/0xd0 [ 168.985036] __sys_sendmsg+0x59/0xa0 [ 168.985477] do_syscall_64+0x79/0x150 [ 168.987273] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 168.987773] RIP: 0033:0x7f8f7950f917

(esw->fdb_table.legacy.vepa_fdb is null)

The bridge mode is only relevant when there are multiple functions per port. Therefore, prevent setting and getting this setting when there are no VFs.

Note that after this change, there are no settings to change on the PF interface using `bridge link` when there are no VFs, so the interface no longer appears in the `bridge link` output.

Fixes: 4b89251de024 ("net/mlx5: Support ndo bridge_setlink and getlink") Signed-off-by: Benjamin Poirier bpoirier@nvidia.com Reviewed-by: Cosmin Ratiu cratiu@nvidia.com Signed-off-by: Saeed Mahameed saeedm@nvidia.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zhang Changzhong zhangchangzhong@huawei.com --- drivers/net/ethernet/mellanox/mlx5/core/esw/legacy.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/esw/legacy.c b/drivers/net/ethernet/mellanox/mlx5/core/esw/legacy.c index 255bc8b..8587cd5 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/esw/legacy.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/esw/legacy.c @@ -319,7 +319,7 @@ int mlx5_eswitch_set_vepa(struct mlx5_eswitch *esw, u8 setting) return -EPERM;

mutex_lock(&esw->state_lock); - if (esw->mode != MLX5_ESWITCH_LEGACY) { + if (esw->mode != MLX5_ESWITCH_LEGACY || !mlx5_esw_is_fdb_created(esw)) { err = -EOPNOTSUPP; goto out; } @@ -339,7 +339,7 @@ int mlx5_eswitch_get_vepa(struct mlx5_eswitch *esw, u8 *setting) if (!mlx5_esw_allowed(esw)) return -EPERM;

- if (esw->mode != MLX5_ESWITCH_LEGACY) + if (esw->mode != MLX5_ESWITCH_LEGACY || !mlx5_esw_is_fdb_created(esw)) return -EOPNOTSUPP;

*setting = esw->fdb_table.legacy.vepa_uplink_rule ? 1 : 0;