lkml.org 
[lkml]   [2020]   [Jan]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: inconsistent lock state in ima_process_queued_keys
From
Date
I am investigating this.

thanks,
-lakshmi

On 1/14/2020 7:21 AM, Dmitry Vyukov wrote:
> On Tue, Jan 14, 2020 at 3:57 PM Mimi Zohar <zohar@linux.ibm.com> wrote:
>>
>> On Tue, 2020-01-14 at 14:58 +0100, Dmitry Vyukov wrote:
>>> On Tue, Jan 14, 2020 at 2:56 PM syzbot
>>> <syzbot+a4a503d7f37292ae1664@syzkaller.appspotmail.com> wrote:
>>>>
>>>> Hello,
>>>>
>>>> syzbot found the following crash on:
>>>>
>>>> HEAD commit: 1b851f98 Add linux-next specific files for 20200114
>>>> git tree: linux-next
>>>> console output: https://syzkaller.appspot.com/x/log.txt?x=12bcbb25e00000
>>>> kernel config: https://syzkaller.appspot.com/x/.config?x=3e7d9cf7ebfa08ad
>>>> dashboard link: https://syzkaller.appspot.com/bug?extid=a4a503d7f37292ae1664
>>>> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
>>>>
>>>> Unfortunately, I don't have any reproducer for this crash yet.
>>>>
>>>> IMPORTANT: if you fix the bug, please add the following tag to the commit:
>>>> Reported-by: syzbot+a4a503d7f37292ae1664@syzkaller.appspotmail.com
>>>
>>> +Lakshmi, you seem to have submitted a number of changes to this file recently.
>>>
>>> This completely breaks linux-next testing for us, every kernel crashes
>>> a few minutes after boot.
>>>
>>> 2020/01/14 14:45:00 vm-26: crash: inconsistent lock state in
>>> ima_process_queued_keys
>>
>> Yikes! Are you running with an IMA policy?
>
> I don't know.
>
>> I assume this is being
>> caused by commit 8f5d2d06f217 ("IMA: Defined timer to free queued
>> keys". Does reverting it prevent this from happening?
>
> The following seems to help, but don't know if it's the right fix or not.
>
> diff --git a/security/integrity/ima/ima_asymmetric_keys.c
> b/security/integrity/ima/ima_asymmetric_keys.c
> index 61e478f9e8199..49d559501fe62 100644
> --- a/security/integrity/ima/ima_asymmetric_keys.c
> +++ b/security/integrity/ima/ima_asymmetric_keys.c
> @@ -103,17 +103,18 @@ static bool ima_queue_key(struct key *keyring,
> const void *payload,
> {
> bool queued = false;
> struct ima_key_entry *entry;
> + unsigned long flags;
>
> entry = ima_alloc_key_entry(keyring, payload, payload_len);
> if (!entry)
> return false;
>
> - spin_lock(&ima_keys_lock);
> + spin_lock_irqsave(&ima_keys_lock, flags);
> if (!ima_process_keys) {
> list_add_tail(&entry->list, &ima_keys);
> queued = true;
> }
> - spin_unlock(&ima_keys_lock);
> + spin_unlock_irqrestore(&ima_keys_lock, flags);
>
> if (!queued)
> ima_free_key_entry(entry);
>

\
 
 \ /
  Last update: 2020-01-14 17:55    [W:0.075 / U:2.244 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site