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* [PATCH iwl-net] idpf: fix xdp crash in soft reset error path
@ 2026-03-18  1:15 Emil Tantilov
  2026-03-18 16:40 ` Alexander Lobakin
  0 siblings, 1 reply; 3+ messages in thread
From: Emil Tantilov @ 2026-03-18  1:15 UTC (permalink / raw)
  To: intel-wired-lan
  Cc: netdev, anthony.l.nguyen, aleksandr.loktionov, przemyslaw.kitszel,
	andrew+netdev, davem, edumazet, kuba, pabeni, ast, daniel, hawk,
	john.fastabend, sdf, bpf, aleksander.lobakin, decot, willemb

NULL pointer dereference is reported in cases where idpf_vport_open()
fails during soft reset:

./xdpsock -i <inf> -q -r -N

[ 3179.186687] idpf 0000:83:00.0: Failed to initialize queue ids for vport 0: -12
[ 3179.276739] BUG: kernel NULL pointer dereference, address: 0000000000000010
[ 3179.277636] #PF: supervisor read access in kernel mode
[ 3179.278470] #PF: error_code(0x0000) - not-present page
[ 3179.279285] PGD 0
[ 3179.280083] Oops: Oops: 0000 [#1] SMP NOPTI
...
[ 3179.283997] Workqueue: events xp_release_deferred
[ 3179.284770] RIP: 0010:idpf_find_rxq_vec+0x17/0x30 [idpf]
...
[ 3179.291937] Call Trace:
[ 3179.292392]  <TASK>
[ 3179.292843]  idpf_qp_switch+0x25/0x820 [idpf]
[ 3179.293325]  idpf_xsk_pool_setup+0x7c/0x520 [idpf]
[ 3179.293803]  idpf_xdp+0x59/0x240 [idpf]
[ 3179.294275]  xp_disable_drv_zc+0x62/0xb0
[ 3179.294743]  xp_clear_dev+0x40/0xb0
[ 3179.295198]  xp_release_deferred+0x1f/0xa0
[ 3179.295648]  process_one_work+0x226/0x730
[ 3179.296106]  worker_thread+0x19e/0x340
[ 3179.296557]  ? __pfx_worker_thread+0x10/0x10
[ 3179.297009]  kthread+0xf4/0x130
[ 3179.297459]  ? __pfx_kthread+0x10/0x10
[ 3179.297910]  ret_from_fork+0x32c/0x410
[ 3179.298361]  ? __pfx_kthread+0x10/0x10
[ 3179.298702]  ret_from_fork_asm+0x1a/0x30

Fix the error handling of the soft reset in idpf_xdp_setup_prog() by
restoring the vport->xdp_prog to the old value. This avoids referencing
the orphaned prog that was copied to vport->xdp_prog in the soft reset
and prevents subsequent false positive by idpf_xdp_enabled().

Update the restart check in idpf_xsk_pool_setup() to use IDPF_VPORT_UP bit
instead of netif_running(). The idpf_vport_stop/start() calls will not
update the __LINK_STATE_START bit, making this test a false positive
should the soft reset fail.

Fixes: 3d57b2c00f09 ("idpf: add XSk pool initialization")
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
---
 drivers/net/ethernet/intel/idpf/xdp.c | 7 ++++++-
 drivers/net/ethernet/intel/idpf/xsk.c | 4 +++-
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/idpf/xdp.c b/drivers/net/ethernet/intel/idpf/xdp.c
index cbccd4546768..b670f0ea20b3 100644
--- a/drivers/net/ethernet/intel/idpf/xdp.c
+++ b/drivers/net/ethernet/intel/idpf/xdp.c
@@ -488,12 +488,17 @@ static int idpf_xdp_setup_prog(struct idpf_vport *vport,
 				   "Could not reopen the vport after XDP setup");
 
 		cfg->user_config.xdp_prog = old;
-		old = prog;
+		vport->xdp_prog = old;
+		if (prog)
+			bpf_prog_put(prog);
+
+		goto out;
 	}
 
 	if (old)
 		bpf_prog_put(old);
 
+out:
 	libeth_xdp_set_redirect(vport->netdev, vport->xdp_prog);
 
 	return ret;
diff --git a/drivers/net/ethernet/intel/idpf/xsk.c b/drivers/net/ethernet/intel/idpf/xsk.c
index d95d3efdfd36..b601b6c298c7 100644
--- a/drivers/net/ethernet/intel/idpf/xsk.c
+++ b/drivers/net/ethernet/intel/idpf/xsk.c
@@ -553,6 +553,7 @@ int idpf_xskrq_poll(struct idpf_rx_queue *rxq, u32 budget)
 
 int idpf_xsk_pool_setup(struct idpf_vport *vport, struct netdev_bpf *bpf)
 {
+	const struct idpf_netdev_priv *np = netdev_priv(vport->netdev);
 	struct xsk_buff_pool *pool = bpf->xsk.pool;
 	u32 qid = bpf->xsk.queue_id;
 	bool restart;
@@ -568,7 +569,8 @@ int idpf_xsk_pool_setup(struct idpf_vport *vport, struct netdev_bpf *bpf)
 		return -EINVAL;
 	}
 
-	restart = idpf_xdp_enabled(vport) && netif_running(vport->netdev);
+	restart = idpf_xdp_enabled(vport) &&
+	       test_bit(IDPF_VPORT_UP, np->state);
 	if (!restart)
 		goto pool;
 
-- 
2.37.3


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH iwl-net] idpf: fix xdp crash in soft reset error path
  2026-03-18  1:15 [PATCH iwl-net] idpf: fix xdp crash in soft reset error path Emil Tantilov
@ 2026-03-18 16:40 ` Alexander Lobakin
  2026-03-19 21:47   ` Tantilov, Emil S
  0 siblings, 1 reply; 3+ messages in thread
From: Alexander Lobakin @ 2026-03-18 16:40 UTC (permalink / raw)
  To: Emil Tantilov
  Cc: intel-wired-lan, netdev, anthony.l.nguyen, aleksandr.loktionov,
	przemyslaw.kitszel, andrew+netdev, davem, edumazet, kuba, pabeni,
	ast, daniel, hawk, john.fastabend, sdf, bpf, decot, willemb

From: Emil Tantilov <emil.s.tantilov@intel.com>
Date: Tue, 17 Mar 2026 18:15:45 -0700

> NULL pointer dereference is reported in cases where idpf_vport_open()
> fails during soft reset:
> 
> ./xdpsock -i <inf> -q -r -N
> 
> [ 3179.186687] idpf 0000:83:00.0: Failed to initialize queue ids for vport 0: -12
> [ 3179.276739] BUG: kernel NULL pointer dereference, address: 0000000000000010
> [ 3179.277636] #PF: supervisor read access in kernel mode
> [ 3179.278470] #PF: error_code(0x0000) - not-present page
> [ 3179.279285] PGD 0
> [ 3179.280083] Oops: Oops: 0000 [#1] SMP NOPTI
> ...
> [ 3179.283997] Workqueue: events xp_release_deferred
> [ 3179.284770] RIP: 0010:idpf_find_rxq_vec+0x17/0x30 [idpf]
> ...
> [ 3179.291937] Call Trace:
> [ 3179.292392]  <TASK>
> [ 3179.292843]  idpf_qp_switch+0x25/0x820 [idpf]
> [ 3179.293325]  idpf_xsk_pool_setup+0x7c/0x520 [idpf]
> [ 3179.293803]  idpf_xdp+0x59/0x240 [idpf]
> [ 3179.294275]  xp_disable_drv_zc+0x62/0xb0
> [ 3179.294743]  xp_clear_dev+0x40/0xb0
> [ 3179.295198]  xp_release_deferred+0x1f/0xa0
> [ 3179.295648]  process_one_work+0x226/0x730
> [ 3179.296106]  worker_thread+0x19e/0x340
> [ 3179.296557]  ? __pfx_worker_thread+0x10/0x10
> [ 3179.297009]  kthread+0xf4/0x130
> [ 3179.297459]  ? __pfx_kthread+0x10/0x10
> [ 3179.297910]  ret_from_fork+0x32c/0x410
> [ 3179.298361]  ? __pfx_kthread+0x10/0x10
> [ 3179.298702]  ret_from_fork_asm+0x1a/0x30
> 
> Fix the error handling of the soft reset in idpf_xdp_setup_prog() by
> restoring the vport->xdp_prog to the old value. This avoids referencing
> the orphaned prog that was copied to vport->xdp_prog in the soft reset
> and prevents subsequent false positive by idpf_xdp_enabled().
> 
> Update the restart check in idpf_xsk_pool_setup() to use IDPF_VPORT_UP bit
> instead of netif_running(). The idpf_vport_stop/start() calls will not
> update the __LINK_STATE_START bit, making this test a false positive
> should the soft reset fail.
> 
> Fixes: 3d57b2c00f09 ("idpf: add XSk pool initialization")
> Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
> ---
>  drivers/net/ethernet/intel/idpf/xdp.c | 7 ++++++-
>  drivers/net/ethernet/intel/idpf/xsk.c | 4 +++-
>  2 files changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/idpf/xdp.c b/drivers/net/ethernet/intel/idpf/xdp.c
> index cbccd4546768..b670f0ea20b3 100644
> --- a/drivers/net/ethernet/intel/idpf/xdp.c
> +++ b/drivers/net/ethernet/intel/idpf/xdp.c
> @@ -488,12 +488,17 @@ static int idpf_xdp_setup_prog(struct idpf_vport *vport,
>  				   "Could not reopen the vport after XDP setup");
>  
>  		cfg->user_config.xdp_prog = old;
> -		old = prog;
> +		vport->xdp_prog = old;

You could just add 1 line here:

 		cfg->user_config.xdp_prog = old;
+		vport->xdp_prog = old;
 		old = prog;

And it would behave the same.

> +		if (prog)
> +			bpf_prog_put(prog);
> +
> +		goto out;
>  	}
>  
>  	if (old)
>  		bpf_prog_put(old);
>  
> +out:
>  	libeth_xdp_set_redirect(vport->netdev, vport->xdp_prog);
>  
>  	return ret;
> diff --git a/drivers/net/ethernet/intel/idpf/xsk.c b/drivers/net/ethernet/intel/idpf/xsk.c
> index d95d3efdfd36..b601b6c298c7 100644
> --- a/drivers/net/ethernet/intel/idpf/xsk.c
> +++ b/drivers/net/ethernet/intel/idpf/xsk.c
> @@ -553,6 +553,7 @@ int idpf_xskrq_poll(struct idpf_rx_queue *rxq, u32 budget)
>  
>  int idpf_xsk_pool_setup(struct idpf_vport *vport, struct netdev_bpf *bpf)
>  {
> +	const struct idpf_netdev_priv *np = netdev_priv(vport->netdev);
>  	struct xsk_buff_pool *pool = bpf->xsk.pool;
>  	u32 qid = bpf->xsk.queue_id;
>  	bool restart;
> @@ -568,7 +569,8 @@ int idpf_xsk_pool_setup(struct idpf_vport *vport, struct netdev_bpf *bpf)
>  		return -EINVAL;
>  	}
>  
> -	restart = idpf_xdp_enabled(vport) && netif_running(vport->netdev);
> +	restart = idpf_xdp_enabled(vport) &&
> +	       test_bit(IDPF_VPORT_UP, np->state);

The indentation is messed up, should be:

	restart = idpf_xdp_enabled(vport) &&
		  test_bit(IDPF_VPORT_UP, np->state);

(two tabs + 2 spaces)

>  	if (!restart)
>  		goto pool;

Thanks,
Olek

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH iwl-net] idpf: fix xdp crash in soft reset error path
  2026-03-18 16:40 ` Alexander Lobakin
@ 2026-03-19 21:47   ` Tantilov, Emil S
  0 siblings, 0 replies; 3+ messages in thread
From: Tantilov, Emil S @ 2026-03-19 21:47 UTC (permalink / raw)
  To: Alexander Lobakin
  Cc: intel-wired-lan, netdev, anthony.l.nguyen, aleksandr.loktionov,
	przemyslaw.kitszel, andrew+netdev, davem, edumazet, kuba, pabeni,
	ast, daniel, hawk, john.fastabend, sdf, bpf, decot, willemb



On 3/18/2026 9:40 AM, Alexander Lobakin wrote:
> From: Emil Tantilov <emil.s.tantilov@intel.com>
> Date: Tue, 17 Mar 2026 18:15:45 -0700
> 
>> NULL pointer dereference is reported in cases where idpf_vport_open()
>> fails during soft reset:
>>
>> ./xdpsock -i <inf> -q -r -N
>>
>> [ 3179.186687] idpf 0000:83:00.0: Failed to initialize queue ids for vport 0: -12
>> [ 3179.276739] BUG: kernel NULL pointer dereference, address: 0000000000000010
>> [ 3179.277636] #PF: supervisor read access in kernel mode
>> [ 3179.278470] #PF: error_code(0x0000) - not-present page
>> [ 3179.279285] PGD 0
>> [ 3179.280083] Oops: Oops: 0000 [#1] SMP NOPTI
>> ...
>> [ 3179.283997] Workqueue: events xp_release_deferred
>> [ 3179.284770] RIP: 0010:idpf_find_rxq_vec+0x17/0x30 [idpf]
>> ...
>> [ 3179.291937] Call Trace:
>> [ 3179.292392]  <TASK>
>> [ 3179.292843]  idpf_qp_switch+0x25/0x820 [idpf]
>> [ 3179.293325]  idpf_xsk_pool_setup+0x7c/0x520 [idpf]
>> [ 3179.293803]  idpf_xdp+0x59/0x240 [idpf]
>> [ 3179.294275]  xp_disable_drv_zc+0x62/0xb0
>> [ 3179.294743]  xp_clear_dev+0x40/0xb0
>> [ 3179.295198]  xp_release_deferred+0x1f/0xa0
>> [ 3179.295648]  process_one_work+0x226/0x730
>> [ 3179.296106]  worker_thread+0x19e/0x340
>> [ 3179.296557]  ? __pfx_worker_thread+0x10/0x10
>> [ 3179.297009]  kthread+0xf4/0x130
>> [ 3179.297459]  ? __pfx_kthread+0x10/0x10
>> [ 3179.297910]  ret_from_fork+0x32c/0x410
>> [ 3179.298361]  ? __pfx_kthread+0x10/0x10
>> [ 3179.298702]  ret_from_fork_asm+0x1a/0x30
>>
>> Fix the error handling of the soft reset in idpf_xdp_setup_prog() by
>> restoring the vport->xdp_prog to the old value. This avoids referencing
>> the orphaned prog that was copied to vport->xdp_prog in the soft reset
>> and prevents subsequent false positive by idpf_xdp_enabled().
>>
>> Update the restart check in idpf_xsk_pool_setup() to use IDPF_VPORT_UP bit
>> instead of netif_running(). The idpf_vport_stop/start() calls will not
>> update the __LINK_STATE_START bit, making this test a false positive
>> should the soft reset fail.
>>
>> Fixes: 3d57b2c00f09 ("idpf: add XSk pool initialization")
>> Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
>> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
>> ---
>>   drivers/net/ethernet/intel/idpf/xdp.c | 7 ++++++-
>>   drivers/net/ethernet/intel/idpf/xsk.c | 4 +++-
>>   2 files changed, 9 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/intel/idpf/xdp.c b/drivers/net/ethernet/intel/idpf/xdp.c
>> index cbccd4546768..b670f0ea20b3 100644
>> --- a/drivers/net/ethernet/intel/idpf/xdp.c
>> +++ b/drivers/net/ethernet/intel/idpf/xdp.c
>> @@ -488,12 +488,17 @@ static int idpf_xdp_setup_prog(struct idpf_vport *vport,
>>   				   "Could not reopen the vport after XDP setup");
>>   
>>   		cfg->user_config.xdp_prog = old;
>> -		old = prog;
>> +		vport->xdp_prog = old;
> 
> You could just add 1 line here:
> 
>   		cfg->user_config.xdp_prog = old;
> +		vport->xdp_prog = old;
>   		old = prog;
> 
> And it would behave the same.

Good catch. Will clean it up in v2.

> 
>> +		if (prog)
>> +			bpf_prog_put(prog);
>> +
>> +		goto out;
>>   	}
>>   
>>   	if (old)
>>   		bpf_prog_put(old);
>>   
>> +out:
>>   	libeth_xdp_set_redirect(vport->netdev, vport->xdp_prog);
>>   
>>   	return ret;
>> diff --git a/drivers/net/ethernet/intel/idpf/xsk.c b/drivers/net/ethernet/intel/idpf/xsk.c
>> index d95d3efdfd36..b601b6c298c7 100644
>> --- a/drivers/net/ethernet/intel/idpf/xsk.c
>> +++ b/drivers/net/ethernet/intel/idpf/xsk.c
>> @@ -553,6 +553,7 @@ int idpf_xskrq_poll(struct idpf_rx_queue *rxq, u32 budget)
>>   
>>   int idpf_xsk_pool_setup(struct idpf_vport *vport, struct netdev_bpf *bpf)
>>   {
>> +	const struct idpf_netdev_priv *np = netdev_priv(vport->netdev);
>>   	struct xsk_buff_pool *pool = bpf->xsk.pool;
>>   	u32 qid = bpf->xsk.queue_id;
>>   	bool restart;
>> @@ -568,7 +569,8 @@ int idpf_xsk_pool_setup(struct idpf_vport *vport, struct netdev_bpf *bpf)
>>   		return -EINVAL;
>>   	}
>>   
>> -	restart = idpf_xdp_enabled(vport) && netif_running(vport->netdev);
>> +	restart = idpf_xdp_enabled(vport) &&
>> +	       test_bit(IDPF_VPORT_UP, np->state);
> 
> The indentation is messed up, should be:
> 
> 	restart = idpf_xdp_enabled(vport) &&
> 		  test_bit(IDPF_VPORT_UP, np->state);
> 
> (two tabs + 2 spaces)

Yeah, will resolve in v2.

Thanks,
Emil

> 
>>   	if (!restart)
>>   		goto pool;
> 
> Thanks,
> Olek


^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2026-03-19 21:47 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2026-03-18  1:15 [PATCH iwl-net] idpf: fix xdp crash in soft reset error path Emil Tantilov
2026-03-18 16:40 ` Alexander Lobakin
2026-03-19 21:47   ` Tantilov, Emil S

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