[RESEND PATCH net 0/2] iavf: Fix issues when setting channels concurrency with removing

[RESEND PATCH net 0/2] iavf: Fix issues when setting channels concurrency with removing

[Ding Hui]

The patchset fix two issues which can be reproduced by the following script:

[root@host ~]# cat test-iavf-1.sh
#!/bin/bash

pf_dbsf="0000:41:00.0"
vf0_dbsf="0000:41:02.0"
g_pids=()

function do_set_numvf()
{
    echo 2 >/sys/bus/pci/devices/${pf_dbsf}/sriov_numvfs
    sleep $((RANDOM%3+1))
    echo 0 >/sys/bus/pci/devices/${pf_dbsf}/sriov_numvfs
    sleep $((RANDOM%3+1))
}

function do_set_channel()
{
    local nic=$(ls -1 --indicator-style=none /sys/bus/pci/devices/${vf0_dbsf}/net/)
    [ -z "$nic" ] && { sleep $((RANDOM%3)) ; return 1; }
    ifconfig $nic 192.168.18.5 netmask 255.255.255.0
    ifconfig $nic up
    ethtool -L $nic combined 1
    ethtool -L $nic combined 4
    sleep $((RANDOM%3))
}

function on_exit()
{
    local pid
    for pid in "${g_pids[@]}"; do
        kill -0 "$pid" &>/dev/null && kill "$pid" &>/dev/null
    done
    g_pids=()
}

trap "on_exit; exit" EXIT

while :; do do_set_numvf ; done &
g_pids+=($!)
while :; do do_set_channel ; done &
g_pids+=($!)

wait


Ding Hui (2):
  iavf: Fix use-after-free in free_netdev
  iavf: Fix out-of-bounds when setting channels on remove

 drivers/net/ethernet/intel/iavf/iavf_ethtool.c | 4 +++-
 drivers/net/ethernet/intel/iavf/iavf_main.c    | 6 +-----
 2 files changed, 4 insertions(+), 6 deletions(-)

-- 
2.17.1

[RESEND PATCH net 1/2] iavf: Fix use-after-free in free_netdev

[Ding Hui]

We do netif_napi_add() for all allocated q_vectors[], but potentially
do netif_napi_del() for part of them, then kfree q_vectors and lefted
invalid pointers at dev->napi_list.

If num_active_queues is changed to less than allocated q_vectors[] by
unexpected, when iavf_remove, we might see UAF in free_netdev like this:

[ 4093.900222] ==================================================================
[ 4093.900230] BUG: KASAN: use-after-free in free_netdev+0x308/0x390
[ 4093.900232] Read of size 8 at addr ffff88b4dc145640 by task test-iavf-1.sh/6699
[ 4093.900233]
[ 4093.900236] CPU: 10 PID: 6699 Comm: test-iavf-1.sh Kdump: loaded Tainted: G           O     --------- -t - 4.18.0 #1
[ 4093.900238] Hardware name: Powerleader PR2008AL/H12DSi-N6, BIOS 2.0 04/09/2021
[ 4093.900239] Call Trace:
[ 4093.900244]  dump_stack+0x71/0xab
[ 4093.900249]  print_address_description+0x6b/0x290
[ 4093.900251]  ? free_netdev+0x308/0x390
[ 4093.900252]  kasan_report+0x14a/0x2b0
[ 4093.900254]  free_netdev+0x308/0x390
[ 4093.900261]  iavf_remove+0x825/0xd20 [iavf]
[ 4093.900265]  pci_device_remove+0xa8/0x1f0
[ 4093.900268]  device_release_driver_internal+0x1c6/0x460
[ 4093.900271]  pci_stop_bus_device+0x101/0x150
[ 4093.900273]  pci_stop_and_remove_bus_device+0xe/0x20
[ 4093.900275]  pci_iov_remove_virtfn+0x187/0x420
[ 4093.900277]  ? pci_iov_add_virtfn+0xe10/0xe10
[ 4093.900278]  ? pci_get_subsys+0x90/0x90
[ 4093.900280]  sriov_disable+0xed/0x3e0
[ 4093.900282]  ? bus_find_device+0x12d/0x1a0
[ 4093.900290]  i40e_free_vfs+0x754/0x1210 [i40e]
[ 4093.900298]  ? i40e_reset_all_vfs+0x880/0x880 [i40e]
[ 4093.900299]  ? pci_get_device+0x7c/0x90
[ 4093.900300]  ? pci_get_subsys+0x90/0x90
[ 4093.900306]  ? pci_vfs_assigned.part.7+0x144/0x210
[ 4093.900309]  ? __mutex_lock_slowpath+0x10/0x10
[ 4093.900315]  i40e_pci_sriov_configure+0x1fa/0x2e0 [i40e]
[ 4093.900318]  sriov_numvfs_store+0x214/0x290
[ 4093.900320]  ? sriov_totalvfs_show+0x30/0x30
[ 4093.900321]  ? __mutex_lock_slowpath+0x10/0x10
[ 4093.900323]  ? __check_object_size+0x15a/0x350
[ 4093.900326]  kernfs_fop_write+0x280/0x3f0
[ 4093.900329]  vfs_write+0x145/0x440
[ 4093.900330]  ksys_write+0xab/0x160
[ 4093.900332]  ? __ia32_sys_read+0xb0/0xb0
[ 4093.900334]  ? fput_many+0x1a/0x120
[ 4093.900335]  ? filp_close+0xf0/0x130
[ 4093.900338]  do_syscall_64+0xa0/0x370
[ 4093.900339]  ? page_fault+0x8/0x30
[ 4093.900341]  entry_SYSCALL_64_after_hwframe+0x65/0xca
[ 4093.900357] RIP: 0033:0x7f16ad4d22c0
[ 4093.900359] Code: 73 01 c3 48 8b 0d d8 cb 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 24 2d 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 fe dd 01 00 48 89 04 24
[ 4093.900360] RSP: 002b:00007ffd6491b7f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 4093.900362] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f16ad4d22c0
[ 4093.900363] RDX: 0000000000000002 RSI: 0000000001a41408 RDI: 0000000000000001
[ 4093.900364] RBP: 0000000001a41408 R08: 00007f16ad7a1780 R09: 00007f16ae1f2700
[ 4093.900364] R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000002
[ 4093.900365] R13: 0000000000000001 R14: 00007f16ad7a0620 R15: 0000000000000001
[ 4093.900367]
[ 4093.900368] Allocated by task 820:
[ 4093.900371]  kasan_kmalloc+0xa6/0xd0
[ 4093.900373]  __kmalloc+0xfb/0x200
[ 4093.900376]  iavf_init_interrupt_scheme+0x63b/0x1320 [iavf]
[ 4093.900380]  iavf_watchdog_task+0x3d51/0x52c0 [iavf]
[ 4093.900382]  process_one_work+0x56a/0x11f0
[ 4093.900383]  worker_thread+0x8f/0xf40
[ 4093.900384]  kthread+0x2a0/0x390
[ 4093.900385]  ret_from_fork+0x1f/0x40
[ 4093.900387]  0xffffffffffffffff
[ 4093.900387]
[ 4093.900388] Freed by task 6699:
[ 4093.900390]  __kasan_slab_free+0x137/0x190
[ 4093.900391]  kfree+0x8b/0x1b0
[ 4093.900394]  iavf_free_q_vectors+0x11d/0x1a0 [iavf]
[ 4093.900397]  iavf_remove+0x35a/0xd20 [iavf]
[ 4093.900399]  pci_device_remove+0xa8/0x1f0
[ 4093.900400]  device_release_driver_internal+0x1c6/0x460
[ 4093.900401]  pci_stop_bus_device+0x101/0x150
[ 4093.900402]  pci_stop_and_remove_bus_device+0xe/0x20
[ 4093.900403]  pci_iov_remove_virtfn+0x187/0x420
[ 4093.900404]  sriov_disable+0xed/0x3e0
[ 4093.900409]  i40e_free_vfs+0x754/0x1210 [i40e]
[ 4093.900415]  i40e_pci_sriov_configure+0x1fa/0x2e0 [i40e]
[ 4093.900416]  sriov_numvfs_store+0x214/0x290
[ 4093.900417]  kernfs_fop_write+0x280/0x3f0
[ 4093.900418]  vfs_write+0x145/0x440
[ 4093.900419]  ksys_write+0xab/0x160
[ 4093.900420]  do_syscall_64+0xa0/0x370
[ 4093.900421]  entry_SYSCALL_64_after_hwframe+0x65/0xca
[ 4093.900422]  0xffffffffffffffff
[ 4093.900422]
[ 4093.900424] The buggy address belongs to the object at ffff88b4dc144200
                which belongs to the cache kmalloc-8k of size 8192
[ 4093.900425] The buggy address is located 5184 bytes inside of
                8192-byte region [ffff88b4dc144200, ffff88b4dc146200)
[ 4093.900425] The buggy address belongs to the page:
[ 4093.900427] page:ffffea00d3705000 refcount:1 mapcount:0 mapping:ffff88bf04415c80 index:0x0 compound_mapcount: 0
[ 4093.900430] flags: 0x10000000008100(slab|head)
[ 4093.900433] raw: 0010000000008100 dead000000000100 dead000000000200 ffff88bf04415c80
[ 4093.900434] raw: 0000000000000000 0000000000030003 00000001ffffffff 0000000000000000
[ 4093.900434] page dumped because: kasan: bad access detected
[ 4093.900435]
[ 4093.900435] Memory state around the buggy address:
[ 4093.900436]  ffff88b4dc145500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 4093.900437]  ffff88b4dc145580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 4093.900438] >ffff88b4dc145600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 4093.900438]                                            ^
[ 4093.900439]  ffff88b4dc145680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 4093.900440]  ffff88b4dc145700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 4093.900440] ==================================================================

Fix it by letting netif_napi_del() match to netif_napi_add().

Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
Cc: Donglin Peng <pengdonglin@sangfor.com.cn>
CC: Huang Cun <huangcun@sangfor.com.cn>
---
 drivers/net/ethernet/intel/iavf/iavf_main.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index 095201e83c9d..a57e3425f960 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -1849,19 +1849,15 @@ static int iavf_alloc_q_vectors(struct iavf_adapter *adapter)
 static void iavf_free_q_vectors(struct iavf_adapter *adapter)
 {
 	int q_idx, num_q_vectors;
-	int napi_vectors;
 
 	if (!adapter->q_vectors)
 		return;
 
 	num_q_vectors = adapter->num_msix_vectors - NONQ_VECS;
-	napi_vectors = adapter->num_active_queues;
 
 	for (q_idx = 0; q_idx < num_q_vectors; q_idx++) {
 		struct iavf_q_vector *q_vector = &adapter->q_vectors[q_idx];
-
-		if (q_idx < napi_vectors)
-			netif_napi_del(&q_vector->napi);
+		netif_napi_del(&q_vector->napi);
 	}
 	kfree(adapter->q_vectors);
 	adapter->q_vectors = NULL;
-- 
2.17.1

[RESEND PATCH net 2/2] iavf: Fix out-of-bounds when setting channels on remove

[Ding Hui]

If we set channels greater when iavf_remove, the waiting reset done
will be timeout, then returned with error but changed num_active_queues
directly, that will lead to OOB like the following logs. Because the
num_active_queues is greater than tx/rx_rings[] allocated actually.

[ 3506.152887] iavf 0000:41:02.0: Removing device
[ 3510.400799] ==================================================================
[ 3510.400820] BUG: KASAN: slab-out-of-bounds in iavf_free_all_tx_resources+0x156/0x160 [iavf]
[ 3510.400823] Read of size 8 at addr ffff88b6f9311008 by task test-iavf-1.sh/55536
[ 3510.400823]
[ 3510.400830] CPU: 101 PID: 55536 Comm: test-iavf-1.sh Kdump: loaded Tainted: G           O     --------- -t - 4.18.0 #1
[ 3510.400832] Hardware name: Powerleader PR2008AL/H12DSi-N6, BIOS 2.0 04/09/2021
[ 3510.400835] Call Trace:
[ 3510.400851]  dump_stack+0x71/0xab
[ 3510.400860]  print_address_description+0x6b/0x290
[ 3510.400865]  ? iavf_free_all_tx_resources+0x156/0x160 [iavf]
[ 3510.400868]  kasan_report+0x14a/0x2b0
[ 3510.400873]  iavf_free_all_tx_resources+0x156/0x160 [iavf]
[ 3510.400880]  iavf_remove+0x2b6/0xc70 [iavf]
[ 3510.400884]  ? iavf_free_all_rx_resources+0x160/0x160 [iavf]
[ 3510.400891]  ? wait_woken+0x1d0/0x1d0
[ 3510.400895]  ? notifier_call_chain+0xc1/0x130
[ 3510.400903]  pci_device_remove+0xa8/0x1f0
[ 3510.400910]  device_release_driver_internal+0x1c6/0x460
[ 3510.400916]  pci_stop_bus_device+0x101/0x150
[ 3510.400919]  pci_stop_and_remove_bus_device+0xe/0x20
[ 3510.400924]  pci_iov_remove_virtfn+0x187/0x420
[ 3510.400927]  ? pci_iov_add_virtfn+0xe10/0xe10
[ 3510.400929]  ? pci_get_subsys+0x90/0x90
[ 3510.400932]  sriov_disable+0xed/0x3e0
[ 3510.400936]  ? bus_find_device+0x12d/0x1a0
[ 3510.400953]  i40e_free_vfs+0x754/0x1210 [i40e]
[ 3510.400966]  ? i40e_reset_all_vfs+0x880/0x880 [i40e]
[ 3510.400968]  ? pci_get_device+0x7c/0x90
[ 3510.400970]  ? pci_get_subsys+0x90/0x90
[ 3510.400982]  ? pci_vfs_assigned.part.7+0x144/0x210
[ 3510.400987]  ? __mutex_lock_slowpath+0x10/0x10
[ 3510.400996]  i40e_pci_sriov_configure+0x1fa/0x2e0 [i40e]
[ 3510.401001]  sriov_numvfs_store+0x214/0x290
[ 3510.401005]  ? sriov_totalvfs_show+0x30/0x30
[ 3510.401007]  ? __mutex_lock_slowpath+0x10/0x10
[ 3510.401011]  ? __check_object_size+0x15a/0x350
[ 3510.401018]  kernfs_fop_write+0x280/0x3f0
[ 3510.401022]  vfs_write+0x145/0x440
[ 3510.401025]  ksys_write+0xab/0x160
[ 3510.401028]  ? __ia32_sys_read+0xb0/0xb0
[ 3510.401031]  ? fput_many+0x1a/0x120
[ 3510.401032]  ? filp_close+0xf0/0x130
[ 3510.401038]  do_syscall_64+0xa0/0x370
[ 3510.401041]  ? page_fault+0x8/0x30
[ 3510.401043]  entry_SYSCALL_64_after_hwframe+0x65/0xca
[ 3510.401073] RIP: 0033:0x7f3a9bb842c0
[ 3510.401079] Code: 73 01 c3 48 8b 0d d8 cb 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 24 2d 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 fe dd 01 00 48 89 04 24
[ 3510.401080] RSP: 002b:00007ffc05f1fe18 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 3510.401083] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f3a9bb842c0
[ 3510.401085] RDX: 0000000000000002 RSI: 0000000002327408 RDI: 0000000000000001
[ 3510.401086] RBP: 0000000002327408 R08: 00007f3a9be53780 R09: 00007f3a9c8a4700
[ 3510.401086] R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000002
[ 3510.401087] R13: 0000000000000001 R14: 00007f3a9be52620 R15: 0000000000000001
[ 3510.401090]
[ 3510.401093] Allocated by task 76795:
[ 3510.401098]  kasan_kmalloc+0xa6/0xd0
[ 3510.401099]  __kmalloc+0xfb/0x200
[ 3510.401104]  iavf_init_interrupt_scheme+0x26f/0x1310 [iavf]
[ 3510.401108]  iavf_watchdog_task+0x1d58/0x4050 [iavf]
[ 3510.401114]  process_one_work+0x56a/0x11f0
[ 3510.401115]  worker_thread+0x8f/0xf40
[ 3510.401117]  kthread+0x2a0/0x390
[ 3510.401119]  ret_from_fork+0x1f/0x40
[ 3510.401122]  0xffffffffffffffff
[ 3510.401123]

If we detected removing is in processing, we can avoid unnecessary
waiting and return error faster.

On the other hand in timeout handling, we should keep the original
num_active_queues and reset num_req_queues to 0.

Fixes: 4e5e6b5d9d13 ("iavf: Fix return of set the new channel count")
Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
Cc: Donglin Peng <pengdonglin@sangfor.com.cn>
CC: Huang Cun <huangcun@sangfor.com.cn>
---
 drivers/net/ethernet/intel/iavf/iavf_ethtool.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/iavf/iavf_ethtool.c b/drivers/net/ethernet/intel/iavf/iavf_ethtool.c
index 6f171d1d85b7..d8a3c0cfedd0 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_ethtool.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_ethtool.c
@@ -1857,13 +1857,15 @@ static int iavf_set_channels(struct net_device *netdev,
 	/* wait for the reset is done */
 	for (i = 0; i < IAVF_RESET_WAIT_COMPLETE_COUNT; i++) {
 		msleep(IAVF_RESET_WAIT_MS);
+		if (test_bit(__IAVF_IN_REMOVE_TASK, &adapter->crit_section))
+			return -EOPNOTSUPP;
 		if (adapter->flags & IAVF_FLAG_RESET_PENDING)
 			continue;
 		break;
 	}
 	if (i == IAVF_RESET_WAIT_COMPLETE_COUNT) {
 		adapter->flags &= ~IAVF_FLAG_REINIT_ITR_NEEDED;
-		adapter->num_active_queues = num_req;
+		adapter->num_req_queues = 0;
 		return -EOPNOTSUPP;
 	}
 
-- 
2.17.1

Re: [RESEND PATCH net 1/2] iavf: Fix use-after-free in free_netdev

[Simon Horman]

Hi Ding Hui,

On Mon, Apr 17, 2023 at 03:40:15PM +0800, Ding Hui wrote:
> We do netif_napi_add() for all allocated q_vectors[], but potentially
> do netif_napi_del() for part of them, then kfree q_vectors and lefted

nit: lefted -> leave

> invalid pointers at dev->napi_list.
> 
> If num_active_queues is changed to less than allocated q_vectors[] by
> unexpected, when iavf_remove, we might see UAF in free_netdev like this:
> 
> [ 4093.900222] ==================================================================
> [ 4093.900230] BUG: KASAN: use-after-free in free_netdev+0x308/0x390
> [ 4093.900232] Read of size 8 at addr ffff88b4dc145640 by task test-iavf-1.sh/6699
> [ 4093.900233]
> [ 4093.900236] CPU: 10 PID: 6699 Comm: test-iavf-1.sh Kdump: loaded Tainted: G           O     --------- -t - 4.18.0 #1
> [ 4093.900238] Hardware name: Powerleader PR2008AL/H12DSi-N6, BIOS 2.0 04/09/2021
> [ 4093.900239] Call Trace:
> [ 4093.900244]  dump_stack+0x71/0xab
> [ 4093.900249]  print_address_description+0x6b/0x290
> [ 4093.900251]  ? free_netdev+0x308/0x390
> [ 4093.900252]  kasan_report+0x14a/0x2b0
> [ 4093.900254]  free_netdev+0x308/0x390
> [ 4093.900261]  iavf_remove+0x825/0xd20 [iavf]
> [ 4093.900265]  pci_device_remove+0xa8/0x1f0
> [ 4093.900268]  device_release_driver_internal+0x1c6/0x460
> [ 4093.900271]  pci_stop_bus_device+0x101/0x150
> [ 4093.900273]  pci_stop_and_remove_bus_device+0xe/0x20
> [ 4093.900275]  pci_iov_remove_virtfn+0x187/0x420
> [ 4093.900277]  ? pci_iov_add_virtfn+0xe10/0xe10
> [ 4093.900278]  ? pci_get_subsys+0x90/0x90
> [ 4093.900280]  sriov_disable+0xed/0x3e0
> [ 4093.900282]  ? bus_find_device+0x12d/0x1a0
> [ 4093.900290]  i40e_free_vfs+0x754/0x1210 [i40e]
> [ 4093.900298]  ? i40e_reset_all_vfs+0x880/0x880 [i40e]
> [ 4093.900299]  ? pci_get_device+0x7c/0x90
> [ 4093.900300]  ? pci_get_subsys+0x90/0x90
> [ 4093.900306]  ? pci_vfs_assigned.part.7+0x144/0x210
> [ 4093.900309]  ? __mutex_lock_slowpath+0x10/0x10
> [ 4093.900315]  i40e_pci_sriov_configure+0x1fa/0x2e0 [i40e]
> [ 4093.900318]  sriov_numvfs_store+0x214/0x290
> [ 4093.900320]  ? sriov_totalvfs_show+0x30/0x30
> [ 4093.900321]  ? __mutex_lock_slowpath+0x10/0x10
> [ 4093.900323]  ? __check_object_size+0x15a/0x350
> [ 4093.900326]  kernfs_fop_write+0x280/0x3f0
> [ 4093.900329]  vfs_write+0x145/0x440
> [ 4093.900330]  ksys_write+0xab/0x160
> [ 4093.900332]  ? __ia32_sys_read+0xb0/0xb0
> [ 4093.900334]  ? fput_many+0x1a/0x120
> [ 4093.900335]  ? filp_close+0xf0/0x130
> [ 4093.900338]  do_syscall_64+0xa0/0x370
> [ 4093.900339]  ? page_fault+0x8/0x30
> [ 4093.900341]  entry_SYSCALL_64_after_hwframe+0x65/0xca
> [ 4093.900357] RIP: 0033:0x7f16ad4d22c0
> [ 4093.900359] Code: 73 01 c3 48 8b 0d d8 cb 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 24 2d 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 fe dd 01 00 48 89 04 24
> [ 4093.900360] RSP: 002b:00007ffd6491b7f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
> [ 4093.900362] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f16ad4d22c0
> [ 4093.900363] RDX: 0000000000000002 RSI: 0000000001a41408 RDI: 0000000000000001
> [ 4093.900364] RBP: 0000000001a41408 R08: 00007f16ad7a1780 R09: 00007f16ae1f2700
> [ 4093.900364] R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000002
> [ 4093.900365] R13: 0000000000000001 R14: 00007f16ad7a0620 R15: 0000000000000001
> [ 4093.900367]
> [ 4093.900368] Allocated by task 820:
> [ 4093.900371]  kasan_kmalloc+0xa6/0xd0
> [ 4093.900373]  __kmalloc+0xfb/0x200
> [ 4093.900376]  iavf_init_interrupt_scheme+0x63b/0x1320 [iavf]
> [ 4093.900380]  iavf_watchdog_task+0x3d51/0x52c0 [iavf]
> [ 4093.900382]  process_one_work+0x56a/0x11f0
> [ 4093.900383]  worker_thread+0x8f/0xf40
> [ 4093.900384]  kthread+0x2a0/0x390
> [ 4093.900385]  ret_from_fork+0x1f/0x40
> [ 4093.900387]  0xffffffffffffffff
> [ 4093.900387]
> [ 4093.900388] Freed by task 6699:
> [ 4093.900390]  __kasan_slab_free+0x137/0x190
> [ 4093.900391]  kfree+0x8b/0x1b0
> [ 4093.900394]  iavf_free_q_vectors+0x11d/0x1a0 [iavf]
> [ 4093.900397]  iavf_remove+0x35a/0xd20 [iavf]
> [ 4093.900399]  pci_device_remove+0xa8/0x1f0
> [ 4093.900400]  device_release_driver_internal+0x1c6/0x460
> [ 4093.900401]  pci_stop_bus_device+0x101/0x150
> [ 4093.900402]  pci_stop_and_remove_bus_device+0xe/0x20
> [ 4093.900403]  pci_iov_remove_virtfn+0x187/0x420
> [ 4093.900404]  sriov_disable+0xed/0x3e0
> [ 4093.900409]  i40e_free_vfs+0x754/0x1210 [i40e]
> [ 4093.900415]  i40e_pci_sriov_configure+0x1fa/0x2e0 [i40e]
> [ 4093.900416]  sriov_numvfs_store+0x214/0x290
> [ 4093.900417]  kernfs_fop_write+0x280/0x3f0
> [ 4093.900418]  vfs_write+0x145/0x440
> [ 4093.900419]  ksys_write+0xab/0x160
> [ 4093.900420]  do_syscall_64+0xa0/0x370
> [ 4093.900421]  entry_SYSCALL_64_after_hwframe+0x65/0xca
> [ 4093.900422]  0xffffffffffffffff
> [ 4093.900422]
> [ 4093.900424] The buggy address belongs to the object at ffff88b4dc144200
>                 which belongs to the cache kmalloc-8k of size 8192
> [ 4093.900425] The buggy address is located 5184 bytes inside of
>                 8192-byte region [ffff88b4dc144200, ffff88b4dc146200)
> [ 4093.900425] The buggy address belongs to the page:
> [ 4093.900427] page:ffffea00d3705000 refcount:1 mapcount:0 mapping:ffff88bf04415c80 index:0x0 compound_mapcount: 0
> [ 4093.900430] flags: 0x10000000008100(slab|head)
> [ 4093.900433] raw: 0010000000008100 dead000000000100 dead000000000200 ffff88bf04415c80
> [ 4093.900434] raw: 0000000000000000 0000000000030003 00000001ffffffff 0000000000000000
> [ 4093.900434] page dumped because: kasan: bad access detected
> [ 4093.900435]
> [ 4093.900435] Memory state around the buggy address:
> [ 4093.900436]  ffff88b4dc145500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> [ 4093.900437]  ffff88b4dc145580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> [ 4093.900438] >ffff88b4dc145600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> [ 4093.900438]                                            ^
> [ 4093.900439]  ffff88b4dc145680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> [ 4093.900440]  ffff88b4dc145700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> [ 4093.900440] ==================================================================
> 
> Fix it by letting netif_napi_del() match to netif_napi_add().
> 
> Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
> Cc: Donglin Peng <pengdonglin@sangfor.com.cn>
> CC: Huang Cun <huangcun@sangfor.com.cn>

as this is a fix it probably should have a fixes tag.
I wonder if it should be:

Fixes: cc0529271f23 ("i40evf: don't use more queues than CPUs")

Code change looks good to me.

Reviewed-by: Simon Horman <simon.horman@corigine.com>

> ---
>  drivers/net/ethernet/intel/iavf/iavf_main.c | 6 +-----
>  1 file changed, 1 insertion(+), 5 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
> index 095201e83c9d..a57e3425f960 100644
> --- a/drivers/net/ethernet/intel/iavf/iavf_main.c
> +++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
> @@ -1849,19 +1849,15 @@ static int iavf_alloc_q_vectors(struct iavf_adapter *adapter)
>  static void iavf_free_q_vectors(struct iavf_adapter *adapter)
>  {
>  	int q_idx, num_q_vectors;
> -	int napi_vectors;
>  
>  	if (!adapter->q_vectors)
>  		return;
>  
>  	num_q_vectors = adapter->num_msix_vectors - NONQ_VECS;
> -	napi_vectors = adapter->num_active_queues;
>  
>  	for (q_idx = 0; q_idx < num_q_vectors; q_idx++) {
>  		struct iavf_q_vector *q_vector = &adapter->q_vectors[q_idx];
> -
> -		if (q_idx < napi_vectors)
> -			netif_napi_del(&q_vector->napi);
> +		netif_napi_del(&q_vector->napi);
>  	}
>  	kfree(adapter->q_vectors);
>  	adapter->q_vectors = NULL;
> -- 
> 2.17.1
> 

Re: [RESEND PATCH net 1/2] iavf: Fix use-after-free in free_netdev

[Simon Horman]

On Tue, Apr 18, 2023 at 09:48:38PM +0200, Simon Horman wrote:
> Hi Ding Hui,
> 
> On Mon, Apr 17, 2023 at 03:40:15PM +0800, Ding Hui wrote:
> > We do netif_napi_add() for all allocated q_vectors[], but potentially
> > do netif_napi_del() for part of them, then kfree q_vectors and lefted
> 
> nit: lefted -> leave
> 
> > invalid pointers at dev->napi_list.
> > 
> > If num_active_queues is changed to less than allocated q_vectors[] by
> > unexpected, when iavf_remove, we might see UAF in free_netdev like this:
> > 
> > [ 4093.900222] ==================================================================
> > [ 4093.900230] BUG: KASAN: use-after-free in free_netdev+0x308/0x390
> > [ 4093.900232] Read of size 8 at addr ffff88b4dc145640 by task test-iavf-1.sh/6699
> > [ 4093.900233]
> > [ 4093.900236] CPU: 10 PID: 6699 Comm: test-iavf-1.sh Kdump: loaded Tainted: G           O     --------- -t - 4.18.0 #1
> > [ 4093.900238] Hardware name: Powerleader PR2008AL/H12DSi-N6, BIOS 2.0 04/09/2021
> > [ 4093.900239] Call Trace:
> > [ 4093.900244]  dump_stack+0x71/0xab
> > [ 4093.900249]  print_address_description+0x6b/0x290
> > [ 4093.900251]  ? free_netdev+0x308/0x390
> > [ 4093.900252]  kasan_report+0x14a/0x2b0
> > [ 4093.900254]  free_netdev+0x308/0x390
> > [ 4093.900261]  iavf_remove+0x825/0xd20 [iavf]
> > [ 4093.900265]  pci_device_remove+0xa8/0x1f0
> > [ 4093.900268]  device_release_driver_internal+0x1c6/0x460
> > [ 4093.900271]  pci_stop_bus_device+0x101/0x150
> > [ 4093.900273]  pci_stop_and_remove_bus_device+0xe/0x20
> > [ 4093.900275]  pci_iov_remove_virtfn+0x187/0x420
> > [ 4093.900277]  ? pci_iov_add_virtfn+0xe10/0xe10
> > [ 4093.900278]  ? pci_get_subsys+0x90/0x90
> > [ 4093.900280]  sriov_disable+0xed/0x3e0
> > [ 4093.900282]  ? bus_find_device+0x12d/0x1a0
> > [ 4093.900290]  i40e_free_vfs+0x754/0x1210 [i40e]
> > [ 4093.900298]  ? i40e_reset_all_vfs+0x880/0x880 [i40e]
> > [ 4093.900299]  ? pci_get_device+0x7c/0x90
> > [ 4093.900300]  ? pci_get_subsys+0x90/0x90
> > [ 4093.900306]  ? pci_vfs_assigned.part.7+0x144/0x210
> > [ 4093.900309]  ? __mutex_lock_slowpath+0x10/0x10
> > [ 4093.900315]  i40e_pci_sriov_configure+0x1fa/0x2e0 [i40e]
> > [ 4093.900318]  sriov_numvfs_store+0x214/0x290
> > [ 4093.900320]  ? sriov_totalvfs_show+0x30/0x30
> > [ 4093.900321]  ? __mutex_lock_slowpath+0x10/0x10
> > [ 4093.900323]  ? __check_object_size+0x15a/0x350
> > [ 4093.900326]  kernfs_fop_write+0x280/0x3f0
> > [ 4093.900329]  vfs_write+0x145/0x440
> > [ 4093.900330]  ksys_write+0xab/0x160
> > [ 4093.900332]  ? __ia32_sys_read+0xb0/0xb0
> > [ 4093.900334]  ? fput_many+0x1a/0x120
> > [ 4093.900335]  ? filp_close+0xf0/0x130
> > [ 4093.900338]  do_syscall_64+0xa0/0x370
> > [ 4093.900339]  ? page_fault+0x8/0x30
> > [ 4093.900341]  entry_SYSCALL_64_after_hwframe+0x65/0xca
> > [ 4093.900357] RIP: 0033:0x7f16ad4d22c0
> > [ 4093.900359] Code: 73 01 c3 48 8b 0d d8 cb 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 24 2d 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 fe dd 01 00 48 89 04 24
> > [ 4093.900360] RSP: 002b:00007ffd6491b7f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
> > [ 4093.900362] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f16ad4d22c0
> > [ 4093.900363] RDX: 0000000000000002 RSI: 0000000001a41408 RDI: 0000000000000001
> > [ 4093.900364] RBP: 0000000001a41408 R08: 00007f16ad7a1780 R09: 00007f16ae1f2700
> > [ 4093.900364] R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000002
> > [ 4093.900365] R13: 0000000000000001 R14: 00007f16ad7a0620 R15: 0000000000000001
> > [ 4093.900367]
> > [ 4093.900368] Allocated by task 820:
> > [ 4093.900371]  kasan_kmalloc+0xa6/0xd0
> > [ 4093.900373]  __kmalloc+0xfb/0x200
> > [ 4093.900376]  iavf_init_interrupt_scheme+0x63b/0x1320 [iavf]
> > [ 4093.900380]  iavf_watchdog_task+0x3d51/0x52c0 [iavf]
> > [ 4093.900382]  process_one_work+0x56a/0x11f0
> > [ 4093.900383]  worker_thread+0x8f/0xf40
> > [ 4093.900384]  kthread+0x2a0/0x390
> > [ 4093.900385]  ret_from_fork+0x1f/0x40
> > [ 4093.900387]  0xffffffffffffffff
> > [ 4093.900387]
> > [ 4093.900388] Freed by task 6699:
> > [ 4093.900390]  __kasan_slab_free+0x137/0x190
> > [ 4093.900391]  kfree+0x8b/0x1b0
> > [ 4093.900394]  iavf_free_q_vectors+0x11d/0x1a0 [iavf]
> > [ 4093.900397]  iavf_remove+0x35a/0xd20 [iavf]
> > [ 4093.900399]  pci_device_remove+0xa8/0x1f0
> > [ 4093.900400]  device_release_driver_internal+0x1c6/0x460
> > [ 4093.900401]  pci_stop_bus_device+0x101/0x150
> > [ 4093.900402]  pci_stop_and_remove_bus_device+0xe/0x20
> > [ 4093.900403]  pci_iov_remove_virtfn+0x187/0x420
> > [ 4093.900404]  sriov_disable+0xed/0x3e0
> > [ 4093.900409]  i40e_free_vfs+0x754/0x1210 [i40e]
> > [ 4093.900415]  i40e_pci_sriov_configure+0x1fa/0x2e0 [i40e]
> > [ 4093.900416]  sriov_numvfs_store+0x214/0x290
> > [ 4093.900417]  kernfs_fop_write+0x280/0x3f0
> > [ 4093.900418]  vfs_write+0x145/0x440
> > [ 4093.900419]  ksys_write+0xab/0x160
> > [ 4093.900420]  do_syscall_64+0xa0/0x370
> > [ 4093.900421]  entry_SYSCALL_64_after_hwframe+0x65/0xca
> > [ 4093.900422]  0xffffffffffffffff
> > [ 4093.900422]
> > [ 4093.900424] The buggy address belongs to the object at ffff88b4dc144200
> >                 which belongs to the cache kmalloc-8k of size 8192
> > [ 4093.900425] The buggy address is located 5184 bytes inside of
> >                 8192-byte region [ffff88b4dc144200, ffff88b4dc146200)
> > [ 4093.900425] The buggy address belongs to the page:
> > [ 4093.900427] page:ffffea00d3705000 refcount:1 mapcount:0 mapping:ffff88bf04415c80 index:0x0 compound_mapcount: 0
> > [ 4093.900430] flags: 0x10000000008100(slab|head)
> > [ 4093.900433] raw: 0010000000008100 dead000000000100 dead000000000200 ffff88bf04415c80
> > [ 4093.900434] raw: 0000000000000000 0000000000030003 00000001ffffffff 0000000000000000
> > [ 4093.900434] page dumped because: kasan: bad access detected
> > [ 4093.900435]
> > [ 4093.900435] Memory state around the buggy address:
> > [ 4093.900436]  ffff88b4dc145500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > [ 4093.900437]  ffff88b4dc145580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > [ 4093.900438] >ffff88b4dc145600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > [ 4093.900438]                                            ^
> > [ 4093.900439]  ffff88b4dc145680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > [ 4093.900440]  ffff88b4dc145700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > [ 4093.900440] ==================================================================
> > 
> > Fix it by letting netif_napi_del() match to netif_napi_add().
> > 
> > Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
> > Cc: Donglin Peng <pengdonglin@sangfor.com.cn>
> > CC: Huang Cun <huangcun@sangfor.com.cn>

Oops, the comment below was meant for
- [RESEND PATCH net 1/2] iavf: Fix use-after-free in free_netdev

> as this is a fix it probably should have a fixes tag.
> I wonder if it should be:
> 
> Fixes: cc0529271f23 ("i40evf: don't use more queues than CPUs")
> 
> Code change looks good to me.
> 
> Reviewed-by: Simon Horman <simon.horman@corigine.com>

Re: [RESEND PATCH net 1/2] iavf: Fix use-after-free in free_netdev

[Simon Horman]

On Tue, Apr 18, 2023 at 09:50:17PM +0200, Simon Horman wrote:
> On Tue, Apr 18, 2023 at 09:48:38PM +0200, Simon Horman wrote:
> > Hi Ding Hui,
> > 
> > On Mon, Apr 17, 2023 at 03:40:15PM +0800, Ding Hui wrote:
> > > We do netif_napi_add() for all allocated q_vectors[], but potentially
> > > do netif_napi_del() for part of them, then kfree q_vectors and lefted
> > 
> > nit: lefted -> leave
> > 
> > > invalid pointers at dev->napi_list.
> > > 
> > > If num_active_queues is changed to less than allocated q_vectors[] by
> > > unexpected, when iavf_remove, we might see UAF in free_netdev like this:
> > > 
> > > [ 4093.900222] ==================================================================
> > > [ 4093.900230] BUG: KASAN: use-after-free in free_netdev+0x308/0x390
> > > [ 4093.900232] Read of size 8 at addr ffff88b4dc145640 by task test-iavf-1.sh/6699
> > > [ 4093.900233]
> > > [ 4093.900236] CPU: 10 PID: 6699 Comm: test-iavf-1.sh Kdump: loaded Tainted: G           O     --------- -t - 4.18.0 #1
> > > [ 4093.900238] Hardware name: Powerleader PR2008AL/H12DSi-N6, BIOS 2.0 04/09/2021
> > > [ 4093.900239] Call Trace:
> > > [ 4093.900244]  dump_stack+0x71/0xab
> > > [ 4093.900249]  print_address_description+0x6b/0x290
> > > [ 4093.900251]  ? free_netdev+0x308/0x390
> > > [ 4093.900252]  kasan_report+0x14a/0x2b0
> > > [ 4093.900254]  free_netdev+0x308/0x390
> > > [ 4093.900261]  iavf_remove+0x825/0xd20 [iavf]
> > > [ 4093.900265]  pci_device_remove+0xa8/0x1f0
> > > [ 4093.900268]  device_release_driver_internal+0x1c6/0x460
> > > [ 4093.900271]  pci_stop_bus_device+0x101/0x150
> > > [ 4093.900273]  pci_stop_and_remove_bus_device+0xe/0x20
> > > [ 4093.900275]  pci_iov_remove_virtfn+0x187/0x420
> > > [ 4093.900277]  ? pci_iov_add_virtfn+0xe10/0xe10
> > > [ 4093.900278]  ? pci_get_subsys+0x90/0x90
> > > [ 4093.900280]  sriov_disable+0xed/0x3e0
> > > [ 4093.900282]  ? bus_find_device+0x12d/0x1a0
> > > [ 4093.900290]  i40e_free_vfs+0x754/0x1210 [i40e]
> > > [ 4093.900298]  ? i40e_reset_all_vfs+0x880/0x880 [i40e]
> > > [ 4093.900299]  ? pci_get_device+0x7c/0x90
> > > [ 4093.900300]  ? pci_get_subsys+0x90/0x90
> > > [ 4093.900306]  ? pci_vfs_assigned.part.7+0x144/0x210
> > > [ 4093.900309]  ? __mutex_lock_slowpath+0x10/0x10
> > > [ 4093.900315]  i40e_pci_sriov_configure+0x1fa/0x2e0 [i40e]
> > > [ 4093.900318]  sriov_numvfs_store+0x214/0x290
> > > [ 4093.900320]  ? sriov_totalvfs_show+0x30/0x30
> > > [ 4093.900321]  ? __mutex_lock_slowpath+0x10/0x10
> > > [ 4093.900323]  ? __check_object_size+0x15a/0x350
> > > [ 4093.900326]  kernfs_fop_write+0x280/0x3f0
> > > [ 4093.900329]  vfs_write+0x145/0x440
> > > [ 4093.900330]  ksys_write+0xab/0x160
> > > [ 4093.900332]  ? __ia32_sys_read+0xb0/0xb0
> > > [ 4093.900334]  ? fput_many+0x1a/0x120
> > > [ 4093.900335]  ? filp_close+0xf0/0x130
> > > [ 4093.900338]  do_syscall_64+0xa0/0x370
> > > [ 4093.900339]  ? page_fault+0x8/0x30
> > > [ 4093.900341]  entry_SYSCALL_64_after_hwframe+0x65/0xca
> > > [ 4093.900357] RIP: 0033:0x7f16ad4d22c0
> > > [ 4093.900359] Code: 73 01 c3 48 8b 0d d8 cb 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 24 2d 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 fe dd 01 00 48 89 04 24
> > > [ 4093.900360] RSP: 002b:00007ffd6491b7f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
> > > [ 4093.900362] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f16ad4d22c0
> > > [ 4093.900363] RDX: 0000000000000002 RSI: 0000000001a41408 RDI: 0000000000000001
> > > [ 4093.900364] RBP: 0000000001a41408 R08: 00007f16ad7a1780 R09: 00007f16ae1f2700
> > > [ 4093.900364] R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000002
> > > [ 4093.900365] R13: 0000000000000001 R14: 00007f16ad7a0620 R15: 0000000000000001
> > > [ 4093.900367]
> > > [ 4093.900368] Allocated by task 820:
> > > [ 4093.900371]  kasan_kmalloc+0xa6/0xd0
> > > [ 4093.900373]  __kmalloc+0xfb/0x200
> > > [ 4093.900376]  iavf_init_interrupt_scheme+0x63b/0x1320 [iavf]
> > > [ 4093.900380]  iavf_watchdog_task+0x3d51/0x52c0 [iavf]
> > > [ 4093.900382]  process_one_work+0x56a/0x11f0
> > > [ 4093.900383]  worker_thread+0x8f/0xf40
> > > [ 4093.900384]  kthread+0x2a0/0x390
> > > [ 4093.900385]  ret_from_fork+0x1f/0x40
> > > [ 4093.900387]  0xffffffffffffffff
> > > [ 4093.900387]
> > > [ 4093.900388] Freed by task 6699:
> > > [ 4093.900390]  __kasan_slab_free+0x137/0x190
> > > [ 4093.900391]  kfree+0x8b/0x1b0
> > > [ 4093.900394]  iavf_free_q_vectors+0x11d/0x1a0 [iavf]
> > > [ 4093.900397]  iavf_remove+0x35a/0xd20 [iavf]
> > > [ 4093.900399]  pci_device_remove+0xa8/0x1f0
> > > [ 4093.900400]  device_release_driver_internal+0x1c6/0x460
> > > [ 4093.900401]  pci_stop_bus_device+0x101/0x150
> > > [ 4093.900402]  pci_stop_and_remove_bus_device+0xe/0x20
> > > [ 4093.900403]  pci_iov_remove_virtfn+0x187/0x420
> > > [ 4093.900404]  sriov_disable+0xed/0x3e0
> > > [ 4093.900409]  i40e_free_vfs+0x754/0x1210 [i40e]
> > > [ 4093.900415]  i40e_pci_sriov_configure+0x1fa/0x2e0 [i40e]
> > > [ 4093.900416]  sriov_numvfs_store+0x214/0x290
> > > [ 4093.900417]  kernfs_fop_write+0x280/0x3f0
> > > [ 4093.900418]  vfs_write+0x145/0x440
> > > [ 4093.900419]  ksys_write+0xab/0x160
> > > [ 4093.900420]  do_syscall_64+0xa0/0x370
> > > [ 4093.900421]  entry_SYSCALL_64_after_hwframe+0x65/0xca
> > > [ 4093.900422]  0xffffffffffffffff
> > > [ 4093.900422]
> > > [ 4093.900424] The buggy address belongs to the object at ffff88b4dc144200
> > >                 which belongs to the cache kmalloc-8k of size 8192
> > > [ 4093.900425] The buggy address is located 5184 bytes inside of
> > >                 8192-byte region [ffff88b4dc144200, ffff88b4dc146200)
> > > [ 4093.900425] The buggy address belongs to the page:
> > > [ 4093.900427] page:ffffea00d3705000 refcount:1 mapcount:0 mapping:ffff88bf04415c80 index:0x0 compound_mapcount: 0
> > > [ 4093.900430] flags: 0x10000000008100(slab|head)
> > > [ 4093.900433] raw: 0010000000008100 dead000000000100 dead000000000200 ffff88bf04415c80
> > > [ 4093.900434] raw: 0000000000000000 0000000000030003 00000001ffffffff 0000000000000000
> > > [ 4093.900434] page dumped because: kasan: bad access detected
> > > [ 4093.900435]
> > > [ 4093.900435] Memory state around the buggy address:
> > > [ 4093.900436]  ffff88b4dc145500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > > [ 4093.900437]  ffff88b4dc145580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > > [ 4093.900438] >ffff88b4dc145600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > > [ 4093.900438]                                            ^
> > > [ 4093.900439]  ffff88b4dc145680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > > [ 4093.900440]  ffff88b4dc145700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > > [ 4093.900440] ==================================================================
> > > 
> > > Fix it by letting netif_napi_del() match to netif_napi_add().
> > > 
> > > Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
> > > Cc: Donglin Peng <pengdonglin@sangfor.com.cn>
> > > CC: Huang Cun <huangcun@sangfor.com.cn>
> 
> Oops, the comment below was meant for
> - [RESEND PATCH net 1/2] iavf: Fix use-after-free in free_netdev

... and this is patch 1/2.
Sorry for (my own) confusion.

> > as this is a fix it probably should have a fixes tag.
> > I wonder if it should be:
> > 
> > Fixes: cc0529271f23 ("i40evf: don't use more queues than CPUs")
> > 
> > Code change looks good to me.
> > 
> > Reviewed-by: Simon Horman <simon.horman@corigine.com>

Re: [RESEND PATCH net 1/2] iavf: Fix use-after-free in free_netdev

[Ding Hui]

On 2023/4/19 3:48, Simon Horman wrote:
> Hi Ding Hui,
> 
> On Mon, Apr 17, 2023 at 03:40:15PM +0800, Ding Hui wrote:
>> We do netif_napi_add() for all allocated q_vectors[], but potentially
>> do netif_napi_del() for part of them, then kfree q_vectors and lefted
> 
> nit: lefted -> leave
> 

Thanks, I'll update in v2.

>> invalid pointers at dev->napi_list.
>>
>> If num_active_queues is changed to less than allocated q_vectors[] by
>> unexpected, when iavf_remove, we might see UAF in free_netdev like this:
>>

...

>>
>> Fix it by letting netif_napi_del() match to netif_napi_add().
>>
>> Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
>> Cc: Donglin Peng <pengdonglin@sangfor.com.cn>
>> CC: Huang Cun <huangcun@sangfor.com.cn>
> 
> as this is a fix it probably should have a fixes tag.
> I wonder if it should be:
> 
> Fixes: cc0529271f23 ("i40evf: don't use more queues than CPUs")

I don't think so.
I searched the git log, and found that the mismatched usage was
introduced since the beginning of i40evf_main.c, so I'll add

Fixes: 5eae00c57f5e ("i40evf: main driver core")

in v2.

> 
> Code change looks good to me.
> 
> Reviewed-by: Simon Horman <simon.horman@corigine.com>
> 

Thanks.

And sorry for you confusion since my RESEND.

>> ---
>>   drivers/net/ethernet/intel/iavf/iavf_main.c | 6 +-----
>>   1 file changed, 1 insertion(+), 5 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
>> index 095201e83c9d..a57e3425f960 100644
>> --- a/drivers/net/ethernet/intel/iavf/iavf_main.c
>> +++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
>> @@ -1849,19 +1849,15 @@ static int iavf_alloc_q_vectors(struct iavf_adapter *adapter)
>>   static void iavf_free_q_vectors(struct iavf_adapter *adapter)
>>   {
>>   	int q_idx, num_q_vectors;
>> -	int napi_vectors;
>>   
>>   	if (!adapter->q_vectors)
>>   		return;
>>   
>>   	num_q_vectors = adapter->num_msix_vectors - NONQ_VECS;
>> -	napi_vectors = adapter->num_active_queues;
>>   
>>   	for (q_idx = 0; q_idx < num_q_vectors; q_idx++) {
>>   		struct iavf_q_vector *q_vector = &adapter->q_vectors[q_idx];
>> -
>> -		if (q_idx < napi_vectors)
>> -			netif_napi_del(&q_vector->napi);
>> +		netif_napi_del(&q_vector->napi);
>>   	}
>>   	kfree(adapter->q_vectors);
>>   	adapter->q_vectors = NULL;
>> -- 
>> 2.17.1
>>
> 

-- 
Thanks,
- Ding Hui

Re: [RESEND PATCH net 1/2] iavf: Fix use-after-free in free_netdev

[Simon Horman]

On Wed, Apr 19, 2023 at 09:11:37AM +0800, Ding Hui wrote:
> On 2023/4/19 3:48, Simon Horman wrote:
> > Hi Ding Hui,
> > 
> > On Mon, Apr 17, 2023 at 03:40:15PM +0800, Ding Hui wrote:
> > > We do netif_napi_add() for all allocated q_vectors[], but potentially
> > > do netif_napi_del() for part of them, then kfree q_vectors and lefted
> > 
> > nit: lefted -> leave
> > 
> 
> Thanks, I'll update in v2.
> 
> > > invalid pointers at dev->napi_list.
> > > 
> > > If num_active_queues is changed to less than allocated q_vectors[] by
> > > unexpected, when iavf_remove, we might see UAF in free_netdev like this:
> > > 
> 
> ...
> 
> > > 
> > > Fix it by letting netif_napi_del() match to netif_napi_add().
> > > 
> > > Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
> > > Cc: Donglin Peng <pengdonglin@sangfor.com.cn>
> > > CC: Huang Cun <huangcun@sangfor.com.cn>
> > 
> > as this is a fix it probably should have a fixes tag.
> > I wonder if it should be:
> > 
> > Fixes: cc0529271f23 ("i40evf: don't use more queues than CPUs")
> 
> I don't think so.
> I searched the git log, and found that the mismatched usage was
> introduced since the beginning of i40evf_main.c, so I'll add
> 
> Fixes: 5eae00c57f5e ("i40evf: main driver core")

Yes, agreed, that is the right tag.