6.6-stable review patch. If anyone has any objections, please let me know.
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From: Ido Schimmel idosch@nvidia.com
[ Upstream commit c28947de2bed40217cf256c5d0d16880054fcf13 ]
The following two shared buffer operations make use of the Shared Buffer Status Register (SBSR):
# devlink sb occupancy snapshot pci/0000:01:00.0 # devlink sb occupancy clearmax pci/0000:01:00.0
The register has two masks of 256 bits to denote on which ingress / egress ports the register should operate on. Spectrum-4 has more than 256 ports, so the register was extended by cited commit with a new 'port_page' field.
However, when filling the register's payload, the driver specifies the ports as absolute numbers and not relative to the first port of the port page, resulting in memory corruptions [1].
Fix by specifying the ports relative to the first port of the port page.
[1] BUG: KASAN: slab-use-after-free in mlxsw_sp_sb_occ_snapshot+0xb6d/0xbc0 Read of size 1 at addr ffff8881068cb00f by task devlink/1566 [...] Call Trace: <TASK> dump_stack_lvl+0xc6/0x120 print_report+0xce/0x670 kasan_report+0xd7/0x110 mlxsw_sp_sb_occ_snapshot+0xb6d/0xbc0 mlxsw_devlink_sb_occ_snapshot+0x75/0xb0 devlink_nl_sb_occ_snapshot_doit+0x1f9/0x2a0 genl_family_rcv_msg_doit+0x20c/0x300 genl_rcv_msg+0x567/0x800 netlink_rcv_skb+0x170/0x450 genl_rcv+0x2d/0x40 netlink_unicast+0x547/0x830 netlink_sendmsg+0x8d4/0xdb0 __sys_sendto+0x49b/0x510 __x64_sys_sendto+0xe5/0x1c0 do_syscall_64+0xc1/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f [...] Allocated by task 1: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 __kasan_kmalloc+0x8f/0xa0 copy_verifier_state+0xbc2/0xfb0 do_check_common+0x2c51/0xc7e0 bpf_check+0x5107/0x9960 bpf_prog_load+0xf0e/0x2690 __sys_bpf+0x1a61/0x49d0 __x64_sys_bpf+0x7d/0xc0 do_syscall_64+0xc1/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 1: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x60 poison_slab_object+0x109/0x170 __kasan_slab_free+0x14/0x30 kfree+0xca/0x2b0 free_verifier_state+0xce/0x270 do_check_common+0x4828/0xc7e0 bpf_check+0x5107/0x9960 bpf_prog_load+0xf0e/0x2690 __sys_bpf+0x1a61/0x49d0 __x64_sys_bpf+0x7d/0xc0 do_syscall_64+0xc1/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f
Fixes: f8538aec88b4 ("mlxsw: Add support for more than 256 ports in SBSR register") Signed-off-by: Ido Schimmel idosch@nvidia.com Reviewed-by: Petr Machata petrm@nvidia.com Reviewed-by: Simon Horman horms@kernel.org Signed-off-by: Petr Machata petrm@nvidia.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- .../mellanox/mlxsw/spectrum_buffers.c | 20 +++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c index c9f1c79f3f9d0..ba090262e27ef 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c @@ -1607,8 +1607,8 @@ static void mlxsw_sp_sb_sr_occ_query_cb(struct mlxsw_core *mlxsw_core, int mlxsw_sp_sb_occ_snapshot(struct mlxsw_core *mlxsw_core, unsigned int sb_index) { + u16 local_port, local_port_1, first_local_port, last_local_port; struct mlxsw_sp *mlxsw_sp = mlxsw_core_driver_priv(mlxsw_core); - u16 local_port, local_port_1, last_local_port; struct mlxsw_sp_sb_sr_occ_query_cb_ctx cb_ctx; u8 masked_count, current_page = 0; unsigned long cb_priv = 0; @@ -1628,6 +1628,7 @@ int mlxsw_sp_sb_occ_snapshot(struct mlxsw_core *mlxsw_core, masked_count = 0; mlxsw_reg_sbsr_pack(sbsr_pl, false); mlxsw_reg_sbsr_port_page_set(sbsr_pl, current_page); + first_local_port = current_page * MLXSW_REG_SBSR_NUM_PORTS_IN_PAGE; last_local_port = current_page * MLXSW_REG_SBSR_NUM_PORTS_IN_PAGE + MLXSW_REG_SBSR_NUM_PORTS_IN_PAGE - 1;
@@ -1645,9 +1646,12 @@ int mlxsw_sp_sb_occ_snapshot(struct mlxsw_core *mlxsw_core, if (local_port != MLXSW_PORT_CPU_PORT) { /* Ingress quotas are not supported for the CPU port */ mlxsw_reg_sbsr_ingress_port_mask_set(sbsr_pl, - local_port, 1); + local_port - first_local_port, + 1); } - mlxsw_reg_sbsr_egress_port_mask_set(sbsr_pl, local_port, 1); + mlxsw_reg_sbsr_egress_port_mask_set(sbsr_pl, + local_port - first_local_port, + 1); for (i = 0; i < mlxsw_sp->sb_vals->pool_count; i++) { err = mlxsw_sp_sb_pm_occ_query(mlxsw_sp, local_port, i, &bulk_list); @@ -1684,7 +1688,7 @@ int mlxsw_sp_sb_occ_max_clear(struct mlxsw_core *mlxsw_core, unsigned int sb_index) { struct mlxsw_sp *mlxsw_sp = mlxsw_core_driver_priv(mlxsw_core); - u16 local_port, last_local_port; + u16 local_port, first_local_port, last_local_port; LIST_HEAD(bulk_list); unsigned int masked_count; u8 current_page = 0; @@ -1702,6 +1706,7 @@ int mlxsw_sp_sb_occ_max_clear(struct mlxsw_core *mlxsw_core, masked_count = 0; mlxsw_reg_sbsr_pack(sbsr_pl, true); mlxsw_reg_sbsr_port_page_set(sbsr_pl, current_page); + first_local_port = current_page * MLXSW_REG_SBSR_NUM_PORTS_IN_PAGE; last_local_port = current_page * MLXSW_REG_SBSR_NUM_PORTS_IN_PAGE + MLXSW_REG_SBSR_NUM_PORTS_IN_PAGE - 1;
@@ -1719,9 +1724,12 @@ int mlxsw_sp_sb_occ_max_clear(struct mlxsw_core *mlxsw_core, if (local_port != MLXSW_PORT_CPU_PORT) { /* Ingress quotas are not supported for the CPU port */ mlxsw_reg_sbsr_ingress_port_mask_set(sbsr_pl, - local_port, 1); + local_port - first_local_port, + 1); } - mlxsw_reg_sbsr_egress_port_mask_set(sbsr_pl, local_port, 1); + mlxsw_reg_sbsr_egress_port_mask_set(sbsr_pl, + local_port - first_local_port, + 1); for (i = 0; i < mlxsw_sp->sb_vals->pool_count; i++) { err = mlxsw_sp_sb_pm_occ_clear(mlxsw_sp, local_port, i, &bulk_list);