2021-11-13 03:42:56

by Letu Ren

[permalink] [raw]
Subject: [PATCH v2] net: igbvf: fix double free in `igbvf_probe`

In `igbvf_probe`, if register_netdev() fails, the program will go to
label err_hw_init, and then to label err_ioremap. In free_netdev() which
is just below label err_ioremap, there is `list_for_each_entry_safe` and
`netif_napi_del` which aims to delete all entries in `dev->napi_list`.
The program has added an entry `adapter->rx_ring->napi` which is added by
`netif_napi_add` in igbvf_alloc_queues(). However, adapter->rx_ring has
been freed below label err_hw_init. So this a UAF.

In terms of how to patch the problem, we can refer to igbvf_remove() and
delete the entry before `adapter->rx_ring`.

The KASAN logs are as follows:

[ 35.126075] BUG: KASAN: use-after-free in free_netdev+0x1fd/0x450
[ 35.127170] Read of size 8 at addr ffff88810126d990 by task modprobe/366
[ 35.128360]
[ 35.128643] CPU: 1 PID: 366 Comm: modprobe Not tainted 5.15.0-rc2+ #14
[ 35.129789] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
[ 35.131749] Call Trace:
[ 35.132199] dump_stack_lvl+0x59/0x7b
[ 35.132865] print_address_description+0x7c/0x3b0
[ 35.133707] ? free_netdev+0x1fd/0x450
[ 35.134378] __kasan_report+0x160/0x1c0
[ 35.135063] ? free_netdev+0x1fd/0x450
[ 35.135738] kasan_report+0x4b/0x70
[ 35.136367] free_netdev+0x1fd/0x450
[ 35.137006] igbvf_probe+0x121d/0x1a10 [igbvf]
[ 35.137808] ? igbvf_vlan_rx_add_vid+0x100/0x100 [igbvf]
[ 35.138751] local_pci_probe+0x13c/0x1f0
[ 35.139461] pci_device_probe+0x37e/0x6c0
[ 35.165526]
[ 35.165806] Allocated by task 366:
[ 35.166414] ____kasan_kmalloc+0xc4/0xf0
[ 35.167117] foo_kmem_cache_alloc_trace+0x3c/0x50 [igbvf]
[ 35.168078] igbvf_probe+0x9c5/0x1a10 [igbvf]
[ 35.168866] local_pci_probe+0x13c/0x1f0
[ 35.169565] pci_device_probe+0x37e/0x6c0
[ 35.179713]
[ 35.179993] Freed by task 366:
[ 35.180539] kasan_set_track+0x4c/0x80
[ 35.181211] kasan_set_free_info+0x1f/0x40
[ 35.181942] ____kasan_slab_free+0x103/0x140
[ 35.182703] kfree+0xe3/0x250
[ 35.183239] igbvf_probe+0x1173/0x1a10 [igbvf]
[ 35.184040] local_pci_probe+0x13c/0x1f0

Fixes: d4e0fe01a38a0 (igbvf: add new driver to support 82576 virtual functions)
Reported-by: Zheyu Ma <[email protected]>
Signed-off-by: Letu Ren <[email protected]>
---
Changes in v2:
- Add fixes tag
---
drivers/net/ethernet/intel/igbvf/netdev.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/intel/igbvf/netdev.c b/drivers/net/ethernet/intel/igbvf/netdev.c
index d32e72d953c8..d051918dfdff 100644
--- a/drivers/net/ethernet/intel/igbvf/netdev.c
+++ b/drivers/net/ethernet/intel/igbvf/netdev.c
@@ -2861,6 +2861,7 @@ static int igbvf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
return 0;

err_hw_init:
+ netif_napi_del(&adapter->rx_ring->napi);
kfree(adapter->tx_ring);
kfree(adapter->rx_ring);
err_sw_init:
--
2.33.1



2021-12-12 12:18:52

by Jankowski, Konrad0

[permalink] [raw]
Subject: RE: [Intel-wired-lan] [PATCH v2] net: igbvf: fix double free in `igbvf_probe`



> -----Original Message-----
> From: Intel-wired-lan <[email protected]> On Behalf Of
> Letu Ren
> Sent: sobota, 13 listopada 2021 04:43
> To: Brandeburg, Jesse <[email protected]>; Nguyen, Anthony L
> <[email protected]>; [email protected]; [email protected]
> Cc: [email protected]; Letu Ren <[email protected]>; intel-
> [email protected]; [email protected]; Zheyu Ma
> <[email protected]>
> Subject: [Intel-wired-lan] [PATCH v2] net: igbvf: fix double free in
> `igbvf_probe`
>
> In `igbvf_probe`, if register_netdev() fails, the program will go to label
> err_hw_init, and then to label err_ioremap. In free_netdev() which is just
> below label err_ioremap, there is `list_for_each_entry_safe` and
> `netif_napi_del` which aims to delete all entries in `dev->napi_list`.
> The program has added an entry `adapter->rx_ring->napi` which is added by
> `netif_napi_add` in igbvf_alloc_queues(). However, adapter->rx_ring has
> been freed below label err_hw_init. So this a UAF.
>
> In terms of how to patch the problem, we can refer to igbvf_remove() and
> delete the entry before `adapter->rx_ring`.
>
> The KASAN logs are as follows:
>
> [ 35.126075] BUG: KASAN: use-after-free in free_netdev+0x1fd/0x450
> [ 35.127170] Read of size 8 at addr ffff88810126d990 by task modprobe/366
> [ 35.128360]
> [ 35.128643] CPU: 1 PID: 366 Comm: modprobe Not tainted 5.15.0-rc2+ #14
> [ 35.129789] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
> rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
> [ 35.131749] Call Trace:
> [ 35.132199] dump_stack_lvl+0x59/0x7b
> [ 35.132865] print_address_description+0x7c/0x3b0
> [ 35.133707] ? free_netdev+0x1fd/0x450
> [ 35.134378] __kasan_report+0x160/0x1c0
> [ 35.135063] ? free_netdev+0x1fd/0x450
> [ 35.135738] kasan_report+0x4b/0x70
> [ 35.136367] free_netdev+0x1fd/0x450
> [ 35.137006] igbvf_probe+0x121d/0x1a10 [igbvf]
> [ 35.137808] ? igbvf_vlan_rx_add_vid+0x100/0x100 [igbvf]
> [ 35.138751] local_pci_probe+0x13c/0x1f0
> [ 35.139461] pci_device_probe+0x37e/0x6c0
> [ 35.165526]
> [ 35.165806] Allocated by task 366:
> [ 35.166414] ____kasan_kmalloc+0xc4/0xf0
> [ 35.167117] foo_kmem_cache_alloc_trace+0x3c/0x50 [igbvf]
> [ 35.168078] igbvf_probe+0x9c5/0x1a10 [igbvf]
> [ 35.168866] local_pci_probe+0x13c/0x1f0
> [ 35.169565] pci_device_probe+0x37e/0x6c0
> [ 35.179713]
> [ 35.179993] Freed by task 366:
> [ 35.180539] kasan_set_track+0x4c/0x80
> [ 35.181211] kasan_set_free_info+0x1f/0x40
> [ 35.181942] ____kasan_slab_free+0x103/0x140
> [ 35.182703] kfree+0xe3/0x250
> [ 35.183239] igbvf_probe+0x1173/0x1a10 [igbvf]
> [ 35.184040] local_pci_probe+0x13c/0x1f0
>
> Fixes: d4e0fe01a38a0 (igbvf: add new driver to support 82576 virtual
> functions)
> Reported-by: Zheyu Ma <[email protected]>
> Signed-off-by: Letu Ren <[email protected]>
> ---
> Changes in v2:
> - Add fixes tag
> ---
> drivers/net/ethernet/intel/igbvf/netdev.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/net/ethernet/intel/igbvf/netdev.c
> b/drivers/net/ethernet/intel/igbvf/netdev.c
> index d32e72d953c8..d051918dfdff 100644
> --- a/drivers/net/ethernet/intel/igbvf/netdev.c
> +++ b/drivers/net/ethernet/intel/igbvf/netdev.c
> @@ -2861,6 +2861,7 @@ static int igbvf_probe(struct pci_dev *pdev, const

Tested-by: Konrad Jankowski <[email protected]>