RE: [Intel-wired-lan] [PATCH 1/2] idpf: skip deallocating bufq_sets from rx_qgrp if it is NULL.

[Salin, Samuel]

> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@xxxxxxxxxx> On Behalf Of
> Loktionov, Aleksandr
> Sent: Monday, January 12, 2026 11:34 PM
> To: Li Li <boolli@xxxxxxxxxx>; Nguyen, Anthony L
> <anthony.l.nguyen@xxxxxxxxx>; Kitszel, Przemyslaw
> <przemyslaw.kitszel@xxxxxxxxx>; David S. Miller <davem@xxxxxxxxxxxxx>;
> Jakub Kicinski <kuba@xxxxxxxxxx>; Eric Dumazet <edumazet@xxxxxxxxxx>;
> intel-wired-lan@xxxxxxxxxxxxxxxx
> Cc: netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; David Decotigny
> <decot@xxxxxxxxxx>; Singhai, Anjali <anjali.singhai@xxxxxxxxx>; Samudrala,
> Sridhar <sridhar.samudrala@xxxxxxxxx>; Brian Vazquez
> <brianvv@xxxxxxxxxx>; Tantilov, Emil S <emil.s.tantilov@xxxxxxxxx>
> Subject: Re: [Intel-wired-lan] [PATCH 1/2] idpf: skip deallocating bufq_sets
> from rx_qgrp if it is NULL.
> 
> 
> 
> > -----Original Message-----
> > From: Intel-wired-lan <intel-wired-lan-bounces@xxxxxxxxxx> On Behalf
> > Of Li Li via Intel-wired-lan
> > Sent: Tuesday, January 13, 2026 12:10 AM
> > To: Nguyen, Anthony L <anthony.l.nguyen@xxxxxxxxx>; Kitszel,
> > Przemyslaw <przemyslaw.kitszel@xxxxxxxxx>; David S. Miller
> > <davem@xxxxxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx>; Eric Dumazet
> > <edumazet@xxxxxxxxxx>; intel-wired-lan@xxxxxxxxxxxxxxxx
> > Cc: netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; David
> > Decotigny <decot@xxxxxxxxxx>; Singhai, Anjali
> > <anjali.singhai@xxxxxxxxx>; Samudrala, Sridhar
> > <sridhar.samudrala@xxxxxxxxx>; Brian Vazquez <brianvv@xxxxxxxxxx>; Li
> > Li <boolli@xxxxxxxxxx>; Tantilov, Emil S <emil.s.tantilov@xxxxxxxxx>
> > Subject: [Intel-wired-lan] [PATCH 1/2] idpf: skip deallocating
> > bufq_sets from rx_qgrp if it is NULL.
> >
> > In idpf_rxq_group_alloc(), if rx_qgrp->splitq.bufq_sets failed to get
> > allocated:
> >
> > 	rx_qgrp->splitq.bufq_sets = kcalloc(vport->num_bufqs_per_qgrp,
> > 					    sizeof(struct idpf_bufq_set),
> > 					    GFP_KERNEL);
> > 	if (!rx_qgrp->splitq.bufq_sets) {
> > 		err = -ENOMEM;
> > 		goto err_alloc;
> > 	}
> >
> > idpf_rxq_group_rel() would attempt to deallocate it in
> > idpf_rxq_sw_queue_rel(), causing a kernel panic:
> >
> > ```
> > [    7.967242] early-network-sshd-n-rexd[3148]: knetbase: Info: [
> > 8.127804] BUG: kernel NULL pointer dereference, address:
> > 00000000000000c0
> > ...
> > [    8.129779] RIP: 0010:idpf_rxq_group_rel+0x101/0x170
> > ...
> > [    8.133854] Call Trace:
> > [    8.133980]  <TASK>
> > [    8.134092]  idpf_vport_queues_alloc+0x286/0x500
> > [    8.134313]  idpf_vport_open+0x4d/0x3f0
> > [    8.134498]  idpf_open+0x71/0xb0
> > [    8.134668]  __dev_open+0x142/0x260
> > [    8.134840]  netif_open+0x2f/0xe0
> > [    8.135004]  dev_open+0x3d/0x70
> > [    8.135166]  bond_enslave+0x5ed/0xf50
> > [    8.135345]  ? nla_put_ifalias+0x3d/0x90
> > [    8.135533]  ? kvfree_call_rcu+0xb5/0x3b0
> > [    8.135725]  ? kvfree_call_rcu+0xb5/0x3b0
> > [    8.135916]  do_set_master+0x114/0x160
> > [    8.136098]  do_setlink+0x412/0xfb0
> > [    8.136269]  ? security_sock_rcv_skb+0x2a/0x50
> > [    8.136509]  ? sk_filter_trim_cap+0x7c/0x320
> > [    8.136714]  ? skb_queue_tail+0x20/0x50
> > [    8.136899]  ? __nla_validate_parse+0x92/0xe50
> > [    8.137112]  ? security_capable+0x35/0x60
> > [    8.137304]  rtnl_newlink+0x95c/0xa00
> > [    8.137483]  ? __rtnl_unlock+0x37/0x70
> > [    8.137664]  ? netdev_run_todo+0x63/0x530
> > [    8.137855]  ? allocate_slab+0x280/0x870
> > [    8.138044]  ? security_capable+0x35/0x60
> > [    8.138235]  rtnetlink_rcv_msg+0x2e6/0x340
> > [    8.138431]  ? __pfx_rtnetlink_rcv_msg+0x10/0x10
> > [    8.138650]  netlink_rcv_skb+0x16a/0x1a0
> > [    8.138840]  netlink_unicast+0x20a/0x320
> > [    8.139028]  netlink_sendmsg+0x304/0x3b0
> > [    8.139217]  __sock_sendmsg+0x89/0xb0
> > [    8.139399]  ____sys_sendmsg+0x167/0x1c0
> > [    8.139588]  ? ____sys_recvmsg+0xed/0x150
> > [    8.139780]  ___sys_sendmsg+0xdd/0x120
> > [    8.139960]  ? ___sys_recvmsg+0x124/0x1e0
> > [    8.140152]  ? rcutree_enqueue+0x1f/0xb0
> > [    8.140341]  ? rcutree_enqueue+0x1f/0xb0
> > [    8.140528]  ? call_rcu+0xde/0x2a0
> > [    8.140695]  ? evict+0x286/0x2d0
> > [    8.140856]  ? rcutree_enqueue+0x1f/0xb0
> > [    8.141043]  ? kmem_cache_free+0x2c/0x350
> > [    8.141236]  __x64_sys_sendmsg+0x72/0xc0
> > [    8.141424]  do_syscall_64+0x6f/0x890
> > [    8.141603]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
> > [    8.141841] RIP: 0033:0x7f2799d21bd0
> > ...
> > [    8.149905] Kernel panic - not syncing: Fatal exception
> > [    8.175940] Kernel Offset: 0xf800000 from 0xffffffff81000000
> > (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
> > [    8.176425] Rebooting in 10 seconds..
> > ```
> >
> > Tested: With this patch, the kernel panic no longer appears.
> > Fixes: 95af467d9a4e ("idpf: configure resources for RX queues")
> >
> > Signed-off-by: Li Li <boolli@xxxxxxxxxx>
> > ---
> >  drivers/net/ethernet/intel/idpf/idpf_txrx.c | 2 ++
> >  1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.c
> > b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
> > index e7b131dba200c..b4dab4a8ee11b 100644
> > --- a/drivers/net/ethernet/intel/idpf/idpf_txrx.c
> > +++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
> > @@ -1337,6 +1337,8 @@ static void idpf_txq_group_rel(struct idpf_vport
> > *vport)  static void idpf_rxq_sw_queue_rel(struct idpf_rxq_group
> > *rx_qgrp)  {
> >  	int i, j;
> > +	if (!rx_qgrp->splitq.bufq_sets)
> > +		return;
> >
> >  	for (i = 0; i < rx_qgrp->vport->num_bufqs_per_qgrp; i++) {
> >  		struct idpf_bufq_set *bufq_set = &rx_qgrp-
> > >splitq.bufq_sets[i];
> > --
> > 2.52.0.457.g6b5491de43-goog
> 
> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@xxxxxxxxx>

Tested-by: Samuel Salin <Samuel.salin@xxxxxxxxx>