diff mbox series

[for-rc] RDMA/core: Call dev_put after query_port in iw_query_port

Message ID 20230519031119.30103-1-guoqing.jiang@linux.dev (mailing list archive)
State Rejected
Headers show
Series [for-rc] RDMA/core: Call dev_put after query_port in iw_query_port | expand

Commit Message

Guoqing Jiang May 19, 2023, 3:11 a.m. UTC 
There is a UAF report by syzbot.

BUG: KASAN: slab-use-after-free in siw_query_port+0x37b/0x3e0 drivers/infiniband/sw/siw/siw_verbs.c:177
Read of size 4 at addr ffff888034efa0e8 by task kworker/1:4/24211

CPU: 1 PID: 24211 Comm: kworker/1:4 Not tainted 6.4.0-rc1-syzkaller-00012-g16a8829130ca #0
Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Workqueue: infiniband ib_cache_event_task
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351
 print_report mm/kasan/report.c:462 [inline]
 kasan_report+0x11c/0x130 mm/kasan/report.c:572
 siw_query_port+0x37b/0x3e0 drivers/infiniband/sw/siw/siw_verbs.c:177
 iw_query_port drivers/infiniband/core/device.c:2049 [inline]
 ib_query_port drivers/infiniband/core/device.c:2090 [inline]
 ib_query_port+0x3c4/0x8f0 drivers/infiniband/core/device.c:2082
 ib_cache_update.part.0+0xcf/0x920 drivers/infiniband/core/cache.c:1487
 ib_cache_update drivers/infiniband/core/cache.c:1561 [inline]
 ib_cache_event_task+0x1b1/0x270 drivers/infiniband/core/cache.c:1561
 process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405
 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2552
 kthread+0x344/0x440 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>

It happened because netdev could be freed if the last reference
is released, but drivers still dereference netdev in query_port.
So let's guard query_port with dev_hold and dev_put.

Reported-by: syzbot+79f283f1f4ccc6e8b624@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/lkml/0000000000001f992805fb79ce97@google.com/
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
---
I guess another option could be call ib_device_get_netdev to get
netdev in siw_query_port instead of dereference netdev directly. 
If so, then other drivers (irdma_query_port and ocrdma_query_port)
may need to make relevant change as well.

 drivers/infiniband/core/device.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

Comments

Jason Gunthorpe May 19, 2023, 2:03 p.m. UTC | #1 
On Fri, May 19, 2023 at 11:11:19AM +0800, Guoqing Jiang wrote:
> There is a UAF report by syzbot.
> 
> BUG: KASAN: slab-use-after-free in siw_query_port+0x37b/0x3e0 drivers/infiniband/sw/siw/siw_verbs.c:177
> Read of size 4 at addr ffff888034efa0e8 by task kworker/1:4/24211
> 
> CPU: 1 PID: 24211 Comm: kworker/1:4 Not tainted 6.4.0-rc1-syzkaller-00012-g16a8829130ca #0
> Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
> Workqueue: infiniband ib_cache_event_task
> Call Trace:
>  <TASK>
>  __dump_stack lib/dump_stack.c:88 [inline]
>  dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
>  print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351
>  print_report mm/kasan/report.c:462 [inline]
>  kasan_report+0x11c/0x130 mm/kasan/report.c:572
>  siw_query_port+0x37b/0x3e0 drivers/infiniband/sw/siw/siw_verbs.c:177
>  iw_query_port drivers/infiniband/core/device.c:2049 [inline]
>  ib_query_port drivers/infiniband/core/device.c:2090 [inline]
>  ib_query_port+0x3c4/0x8f0 drivers/infiniband/core/device.c:2082
>  ib_cache_update.part.0+0xcf/0x920 drivers/infiniband/core/cache.c:1487
>  ib_cache_update drivers/infiniband/core/cache.c:1561 [inline]
>  ib_cache_event_task+0x1b1/0x270 drivers/infiniband/core/cache.c:1561
>  process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405
>  worker_thread+0x67d/0x10c0 kernel/workqueue.c:2552
>  kthread+0x344/0x440 kernel/kthread.c:379
>  ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
>  </TASK>
> 
> It happened because netdev could be freed if the last reference
> is released, but drivers still dereference netdev in query_port.
> So let's guard query_port with dev_hold and dev_put.
> 
> Reported-by: syzbot+79f283f1f4ccc6e8b624@syzkaller.appspotmail.com
> Closes: https://lore.kernel.org/lkml/0000000000001f992805fb79ce97@google.com/
> Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
> ---
> I guess another option could be call ib_device_get_netdev to get
> netdev in siw_query_port instead of dereference netdev directly. 
> If so, then other drivers (irdma_query_port and ocrdma_query_port)
> may need to make relevant change as well.

Something is wrong in siw if it is UAF'ing it's own memory:

	attr->max_mtu = ib_mtu_int_to_enum(sdev->netdev->mtu);

It needs to protect sedv->netdev somehow on its own.

Jason
Chuck Lever May 19, 2023, 2:05 p.m. UTC | #2 
> On May 19, 2023, at 10:03 AM, Jason Gunthorpe <jgg@ziepe.ca> wrote:
> 
> On Fri, May 19, 2023 at 11:11:19AM +0800, Guoqing Jiang wrote:
>> There is a UAF report by syzbot.
>> 
>> BUG: KASAN: slab-use-after-free in siw_query_port+0x37b/0x3e0 drivers/infiniband/sw/siw/siw_verbs.c:177
>> Read of size 4 at addr ffff888034efa0e8 by task kworker/1:4/24211
>> 
>> CPU: 1 PID: 24211 Comm: kworker/1:4 Not tainted 6.4.0-rc1-syzkaller-00012-g16a8829130ca #0
>> Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
>> Workqueue: infiniband ib_cache_event_task
>> Call Trace:
>> <TASK>
>> __dump_stack lib/dump_stack.c:88 [inline]
>> dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
>> print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351
>> print_report mm/kasan/report.c:462 [inline]
>> kasan_report+0x11c/0x130 mm/kasan/report.c:572
>> siw_query_port+0x37b/0x3e0 drivers/infiniband/sw/siw/siw_verbs.c:177
>> iw_query_port drivers/infiniband/core/device.c:2049 [inline]
>> ib_query_port drivers/infiniband/core/device.c:2090 [inline]
>> ib_query_port+0x3c4/0x8f0 drivers/infiniband/core/device.c:2082
>> ib_cache_update.part.0+0xcf/0x920 drivers/infiniband/core/cache.c:1487
>> ib_cache_update drivers/infiniband/core/cache.c:1561 [inline]
>> ib_cache_event_task+0x1b1/0x270 drivers/infiniband/core/cache.c:1561
>> process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405
>> worker_thread+0x67d/0x10c0 kernel/workqueue.c:2552
>> kthread+0x344/0x440 kernel/kthread.c:379
>> ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
>> </TASK>
>> 
>> It happened because netdev could be freed if the last reference
>> is released, but drivers still dereference netdev in query_port.
>> So let's guard query_port with dev_hold and dev_put.
>> 
>> Reported-by: syzbot+79f283f1f4ccc6e8b624@syzkaller.appspotmail.com
>> Closes: https://lore.kernel.org/lkml/0000000000001f992805fb79ce97@google.com/
>> Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
>> ---
>> I guess another option could be call ib_device_get_netdev to get
>> netdev in siw_query_port instead of dereference netdev directly. 
>> If so, then other drivers (irdma_query_port and ocrdma_query_port)
>> may need to make relevant change as well.
> 
> Something is wrong in siw if it is UAF'ing it's own memory:
> 
> attr->max_mtu = ib_mtu_int_to_enum(sdev->netdev->mtu);
> 
> It needs to protect sedv->netdev somehow on its own.

Note that netdev is actually the underlying device. An siw device
doesn't have its own. But maybe it should.

--
Chuck Lever
Guoqing Jiang May 22, 2023, 2:34 a.m. UTC | #3 
On 5/19/23 22:05, Chuck Lever III wrote:
>
>> On May 19, 2023, at 10:03 AM, Jason Gunthorpe <jgg@ziepe.ca> wrote:
>>
>> On Fri, May 19, 2023 at 11:11:19AM +0800, Guoqing Jiang wrote:
>>> There is a UAF report by syzbot.
>>>
>>> BUG: KASAN: slab-use-after-free in siw_query_port+0x37b/0x3e0 drivers/infiniband/sw/siw/siw_verbs.c:177
>>> Read of size 4 at addr ffff888034efa0e8 by task kworker/1:4/24211
>>>
>>> CPU: 1 PID: 24211 Comm: kworker/1:4 Not tainted 6.4.0-rc1-syzkaller-00012-g16a8829130ca #0
>>> Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
>>> Workqueue: infiniband ib_cache_event_task
>>> Call Trace:
>>> <TASK>
>>> __dump_stack lib/dump_stack.c:88 [inline]
>>> dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
>>> print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351
>>> print_report mm/kasan/report.c:462 [inline]
>>> kasan_report+0x11c/0x130 mm/kasan/report.c:572
>>> siw_query_port+0x37b/0x3e0 drivers/infiniband/sw/siw/siw_verbs.c:177
>>> iw_query_port drivers/infiniband/core/device.c:2049 [inline]
>>> ib_query_port drivers/infiniband/core/device.c:2090 [inline]
>>> ib_query_port+0x3c4/0x8f0 drivers/infiniband/core/device.c:2082
>>> ib_cache_update.part.0+0xcf/0x920 drivers/infiniband/core/cache.c:1487
>>> ib_cache_update drivers/infiniband/core/cache.c:1561 [inline]
>>> ib_cache_event_task+0x1b1/0x270 drivers/infiniband/core/cache.c:1561
>>> process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405
>>> worker_thread+0x67d/0x10c0 kernel/workqueue.c:2552
>>> kthread+0x344/0x440 kernel/kthread.c:379
>>> ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
>>> </TASK>
>>>
>>> It happened because netdev could be freed if the last reference
>>> is released, but drivers still dereference netdev in query_port.
>>> So let's guard query_port with dev_hold and dev_put.
>>>
>>> Reported-by: syzbot+79f283f1f4ccc6e8b624@syzkaller.appspotmail.com
>>> Closes: https://lore.kernel.org/lkml/0000000000001f992805fb79ce97@google.com/
>>> Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
>>> ---
>>> I guess another option could be call ib_device_get_netdev to get
>>> netdev in siw_query_port instead of dereference netdev directly.
>>> If so, then other drivers (irdma_query_port and ocrdma_query_port)
>>> may need to make relevant change as well.
>> Something is wrong in siw if it is UAF'ing it's own memory:
>>
>> attr->max_mtu = ib_mtu_int_to_enum(sdev->netdev->mtu);
>>
>> It needs to protect sedv->netdev somehow on its own.
> Note that netdev is actually the underlying device. An siw device
> doesn't have its own. But maybe it should.

I go through siw code a bit, and can't find relevant protection in siw.
Let me cc Bernard.

Thanks,
Guoqing
diff mbox series

Patch

diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index a666847bd714..1f0aabeabc4e 100644
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -2016,6 +2016,7 @@  static int iw_query_port(struct ib_device *device,
 {
 	struct in_device *inetdev;
 	struct net_device *netdev;
+	int ret;
 
 	memset(port_attr, 0, sizeof(*port_attr));
 
@@ -2045,8 +2046,13 @@  static int iw_query_port(struct ib_device *device,
 		rcu_read_unlock();
 	}
 
+	/*
+	 * netdev need to be put after query port since it might be dereferenced
+	 * in some drivers such as siw.
+	 */
+	ret = device->ops.query_port(device, port_num, port_attr);
 	dev_put(netdev);
-	return device->ops.query_port(device, port_num, port_attr);
+	return ret;
 }
 
 static int __ib_query_port(struct ib_device *device,