On 2023/12/4 1:50, Simon Horman wrote:
On Thu, Nov 30, 2023 at 01:46:56AM -0800, Shifeng Li wrote:
Out_sz that the size of out buffer is calculated using query_nic_vport
_context_in structure when driver query the MAC list. However query_nic
_vport_context_in structure is smaller than query_nic_vport_context_out.
When allowed_list_size is greater than 96, calling ether_addr_copy() will
trigger an slab-out-of-bounds.
[ 1170.055866] BUG: KASAN: slab-out-of-bounds in mlx5_query_nic_vport_mac_list+0x481/0x4d0 [mlx5_core]
[ 1170.055869] Read of size 4 at addr ffff88bdbc57d912 by task kworker/u128:1/461
[ 1170.055870]
[ 1170.055932] Workqueue: mlx5_esw_wq esw_vport_change_handler [mlx5_core]
[ 1170.055936] Call Trace:
[ 1170.055949] dump_stack+0x8b/0xbb
[ 1170.055958] print_address_description+0x6a/0x270
[ 1170.055961] kasan_report+0x179/0x2c0
[ 1170.056061] mlx5_query_nic_vport_mac_list+0x481/0x4d0 [mlx5_core]
[ 1170.056162] esw_update_vport_addr_list+0x2c5/0xcd0 [mlx5_core]
[ 1170.056257] esw_vport_change_handle_locked+0xd08/0x1a20 [mlx5_core]
[ 1170.056377] esw_vport_change_handler+0x6b/0x90 [mlx5_core]
[ 1170.056381] process_one_work+0x65f/0x12d0
[ 1170.056383] worker_thread+0x87/0xb50
[ 1170.056390] kthread+0x2e9/0x3a0
[ 1170.056394] ret_from_fork+0x1f/0x40
Fixes: e16aea2744ab ("net/mlx5: Introduce access functions to modify/query vport mac lists")
Cc: Ding Hui <dinghui@xxxxxxxxxxxxxx>
Signed-off-by: Shifeng Li <lishifeng@xxxxxxxxxxxxxx>
Hi,
I am unsure how you calculated the 96 figure above.
But in any case I agree that the cited patch introduced
the mismatch that you describe.
out_sz = MLX5_ST_SZ_BYTES(query_nic_vport_context_in) + req_list_size * MLX5_ST_SZ_BYTES(mac_address_layout)
= 0x80/8 + 128 * 0x40/8 = 0x410 (bytes)
nic_vport_ctx = MLX5_ADDR_OF(query_nic_vport_context_out, out, nic_vport_context)
= 0x880/8 = 0x110 (bytes)
mac_addr = MLX5_ADDR_OF(nic_vport_context, nic_vport_ctx, current_uc_mac_address[96]) + 2
= 0x110 + 96 * 8 + 2
= 0x412 (bytes)
When i is 96, the mac_addr offset is 0x412 but the out_sz is 0x410.
And that will trigger an slab-out-of-bounds.
Thanks.
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
