Re: [net v2 1/1] ice: Fix crash by keep old cfg when update TCs more than queues

From: Anatolii Gerasymenko
Date: Tue Aug 16 2022 - 06:29:01 EST

On 15.08.2022 03:18, Ding Hui wrote:
> There are problems if allocated queues less than Traffic Classes.
>
> Commit a632b2a4c920 ("ice: ethtool: Prohibit improper channel config
> for DCB") already disallow setting less queues than TCs.
>
> Another case is if we first set less queues, and later update more TCs
> config due to LLDP, ice_vsi_cfg_tc() will failed but left dirty
> num_txq/rxq and tc_cfg in vsi, that will cause invalid porinter access.

Nice catch. Looks good to me.

> [ 95.968089] ice 0000:3b:00.1: More TCs defined than queues/rings allocated.
> [ 95.968092] ice 0000:3b:00.1: Trying to use more Rx queues (8), than were allocated (1)!
> [ 95.968093] ice 0000:3b:00.1: Failed to config TC for VSI index: 0
> [ 95.969621] general protection fault: 0000 [#1] SMP NOPTI
> [ 95.969705] CPU: 1 PID: 58405 Comm: lldpad Kdump: loaded Tainted: G U W O --------- -t - 4.18.0 #1
> [ 95.969867] Hardware name: O.E.M/BC11SPSCB10, BIOS 8.23 12/30/2021
> [ 95.969992] RIP: 0010:devm_kmalloc+0xa/0x60
> [ 95.970052] Code: 5c ff ff ff 31 c0 5b 5d 41 5c c3 b8 f4 ff ff ff eb f4 0f 1f 40 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 89 d1 <8b> 97 60 02 00 00 48 8d 7e 18 48 39 f7 72 3f 55 89 ce 53 48 8b 4c
> [ 95.970344] RSP: 0018:ffffc9003f553888 EFLAGS: 00010206
> [ 95.970425] RAX: dead000000000200 RBX: ffffea003c425b00 RCX: 00000000006080c0
> [ 95.970536] RDX: 00000000006080c0 RSI: 0000000000000200 RDI: dead000000000200
> [ 95.970648] RBP: dead000000000200 R08: 00000000000463c0 R09: ffff888ffa900000
> [ 95.970760] R10: 0000000000000000 R11: 0000000000000002 R12: ffff888ff6b40100
> [ 95.970870] R13: ffff888ff6a55018 R14: 0000000000000000 R15: ffff888ff6a55460
> [ 95.970981] FS: 00007f51b7d24700(0000) GS:ffff88903ee80000(0000) knlGS:0000000000000000
> [ 95.971108] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 95.971197] CR2: 00007fac5410d710 CR3: 0000000f2c1de002 CR4: 00000000007606e0
> [ 95.971309] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [ 95.971419] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [ 95.971530] PKRU: 55555554
> [ 95.971573] Call Trace:
> [ 95.971622] ice_setup_rx_ring+0x39/0x110 [ice]
> [ 95.971695] ice_vsi_setup_rx_rings+0x54/0x90 [ice]
> [ 95.971774] ice_vsi_open+0x25/0x120 [ice]
> [ 95.971843] ice_open_internal+0xb8/0x1f0 [ice]
> [ 95.971919] ice_ena_vsi+0x4f/0xd0 [ice]
> [ 95.971987] ice_dcb_ena_dis_vsi.constprop.5+0x29/0x90 [ice]
> [ 95.972082] ice_pf_dcb_cfg+0x29a/0x380 [ice]
> [ 95.972154] ice_dcbnl_setets+0x174/0x1b0 [ice]
> [ 95.972220] dcbnl_ieee_set+0x89/0x230
> [ 95.972279] ? dcbnl_ieee_del+0x150/0x150
> [ 95.972341] dcb_doit+0x124/0x1b0
> [ 95.972392] rtnetlink_rcv_msg+0x243/0x2f0
> [ 95.972457] ? dcb_doit+0x14d/0x1b0
> [ 95.972510] ? __kmalloc_node_track_caller+0x1d3/0x280
> [ 95.972591] ? rtnl_calcit.isra.31+0x100/0x100
> [ 95.972661] netlink_rcv_skb+0xcf/0xf0
> [ 95.972720] netlink_unicast+0x16d/0x220
> [ 95.972781] netlink_sendmsg+0x2ba/0x3a0
> [ 95.975891] sock_sendmsg+0x4c/0x50
> [ 95.979032] ___sys_sendmsg+0x2e4/0x300
> [ 95.982147] ? kmem_cache_alloc+0x13e/0x190
> [ 95.985242] ? __wake_up_common_lock+0x79/0x90
> [ 95.988338] ? __check_object_size+0xac/0x1b0
> [ 95.991440] ? _copy_to_user+0x22/0x30
> [ 95.994539] ? move_addr_to_user+0xbb/0xd0
> [ 95.997619] ? __sys_sendmsg+0x53/0x80
> [ 96.000664] __sys_sendmsg+0x53/0x80
> [ 96.003747] do_syscall_64+0x5b/0x1d0
> [ 96.006862] entry_SYSCALL_64_after_hwframe+0x65/0xca
>
> Only update num_txq/rxq when passed check, and restore tc_cfg if setup
> queue map failed.
>
> Signed-off-by: Ding Hui <dinghui@xxxxxxxxxxxxxx>

Please, also add Fixes tag.

> ---
> drivers/net/ethernet/intel/ice/ice_lib.c | 42 +++++++++++++++---------
> 1 file changed, 26 insertions(+), 16 deletions(-)
>
> ---
> v1:
> https://patchwork.kernel.org/project/netdevbpf/patch/20220812123933.5481-1-dinghui@xxxxxxxxxxxxxx/
>
> v2:
> rewrite subject
> rebase to net
>
> diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c b/drivers/net/ethernet/intel/ice/ice_lib.c
> index a830f7f9aed0..6e64cca30351 100644
> --- a/drivers/net/ethernet/intel/ice/ice_lib.c
> +++ b/drivers/net/ethernet/intel/ice/ice_lib.c
> @@ -914,7 +914,7 @@ static void ice_set_dflt_vsi_ctx(struct ice_hw *hw, struct ice_vsi_ctx *ctxt)
> */
> static int ice_vsi_setup_q_map(struct ice_vsi *vsi, struct ice_vsi_ctx *ctxt)
> {
> - u16 offset = 0, qmap = 0, tx_count = 0, pow = 0;
> + u16 offset = 0, qmap = 0, tx_count = 0, rx_count = 0, pow = 0;
> u16 num_txq_per_tc, num_rxq_per_tc;
> u16 qcount_tx = vsi->alloc_txq;
> u16 qcount_rx = vsi->alloc_rxq;
> @@ -981,23 +981,25 @@ static int ice_vsi_setup_q_map(struct ice_vsi *vsi, struct ice_vsi_ctx *ctxt)
> * at least 1)
> */
> if (offset)
> - vsi->num_rxq = offset;
> + rx_count = offset;
> else
> - vsi->num_rxq = num_rxq_per_tc;
> + rx_count = num_rxq_per_tc;
>
> - if (vsi->num_rxq > vsi->alloc_rxq) {
> + if (rx_count > vsi->alloc_rxq) {
> dev_err(ice_pf_to_dev(vsi->back), "Trying to use more Rx queues (%u), than were allocated (%u)!\n",
> - vsi->num_rxq, vsi->alloc_rxq);
> + rx_count, vsi->alloc_rxq);
> return -EINVAL;
> }
>
> - vsi->num_txq = tx_count;
> - if (vsi->num_txq > vsi->alloc_txq) {
> + if (tx_count > vsi->alloc_txq) {
> dev_err(ice_pf_to_dev(vsi->back), "Trying to use more Tx queues (%u), than were allocated (%u)!\n",
> - vsi->num_txq, vsi->alloc_txq);
> + tx_count, vsi->alloc_txq);
> return -EINVAL;
> }
>
> + vsi->num_txq = tx_count;
> + vsi->num_rxq = rx_count;
> +
> if (vsi->type == ICE_VSI_VF && vsi->num_txq != vsi->num_rxq) {
> dev_dbg(ice_pf_to_dev(vsi->back), "VF VSI should have same number of Tx and Rx queues. Hence making them equal\n");
> /* since there is a chance that num_rxq could have been changed
> @@ -3492,6 +3494,7 @@ ice_vsi_setup_q_map_mqprio(struct ice_vsi *vsi, struct ice_vsi_ctx *ctxt,
> int tc0_qcount = vsi->mqprio_qopt.qopt.count[0];
> u8 netdev_tc = 0;
> int i;
> + u16 new_txq, new_rxq;

Please follow the Reverse Christmas Tree (RCT) convention.

> vsi->tc_cfg.ena_tc = ena_tc ? ena_tc : 1;
>
> @@ -3530,21 +3533,24 @@ ice_vsi_setup_q_map_mqprio(struct ice_vsi *vsi, struct ice_vsi_ctx *ctxt,
> }
> }
>
> - /* Set actual Tx/Rx queue pairs */
> - vsi->num_txq = offset + qcount_tx;
> - if (vsi->num_txq > vsi->alloc_txq) {
> + new_txq = offset + qcount_tx;
> + if (new_txq > vsi->alloc_txq) {
> dev_err(ice_pf_to_dev(vsi->back), "Trying to use more Tx queues (%u), than were allocated (%u)!\n",
> - vsi->num_txq, vsi->alloc_txq);
> + new_txq, vsi->alloc_txq);
> return -EINVAL;
> }
>
> - vsi->num_rxq = offset + qcount_rx;
> - if (vsi->num_rxq > vsi->alloc_rxq) {
> + new_rxq = offset + qcount_rx;
> + if (new_rxq > vsi->alloc_rxq) {
> dev_err(ice_pf_to_dev(vsi->back), "Trying to use more Rx queues (%u), than were allocated (%u)!\n",
> - vsi->num_rxq, vsi->alloc_rxq);
> + new_rxq, vsi->alloc_rxq);
> return -EINVAL;
> }
>
> + /* Set actual Tx/Rx queue pairs */
> + vsi->num_txq = new_txq;
> + vsi->num_rxq = new_rxq;
> +
> /* Setup queue TC[0].qmap for given VSI context */
> ctxt->info.tc_mapping[0] = cpu_to_le16(qmap);
> ctxt->info.q_mapping[0] = cpu_to_le16(vsi->rxq_map[0]);
> @@ -3580,6 +3586,7 @@ int ice_vsi_cfg_tc(struct ice_vsi *vsi, u8 ena_tc)
> struct device *dev;
> int i, ret = 0;
> u8 num_tc = 0;
> + struct ice_tc_cfg old_tc_cfg;

RCT here also.

> dev = ice_pf_to_dev(pf);
> if (vsi->tc_cfg.ena_tc == ena_tc &&
> @@ -3600,6 +3607,7 @@ int ice_vsi_cfg_tc(struct ice_vsi *vsi, u8 ena_tc)
> max_txqs[i] = vsi->num_txq;
> }
>
> + memcpy(&old_tc_cfg, &vsi->tc_cfg, sizeof(old_tc_cfg));
> vsi->tc_cfg.ena_tc = ena_tc;
> vsi->tc_cfg.numtc = num_tc;
>
> @@ -3616,8 +3624,10 @@ int ice_vsi_cfg_tc(struct ice_vsi *vsi, u8 ena_tc)
> else
> ret = ice_vsi_setup_q_map(vsi, ctx);
>
> - if (ret)
> + if (ret) {
> + memcpy(&vsi->tc_cfg, &old_tc_cfg, sizeof(vsi->tc_cfg));
> goto out;
> + }
>
> /* must to indicate which section of VSI context are being modified */
> ctx->info.valid_sections = cpu_to_le16(ICE_AQ_VSI_PROP_RXQ_MAP_VALID);