lkml.org 
[lkml]   [2014]   [Sep]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] fsnotify: don't put user context if it was never assigned
Ping?

On 09/03/2014 05:31 PM, Sasha Levin wrote:
> Ping? This is a NULL ptr deref that userspace can trigger.
>
> On 07/29/2014 09:25 AM, Sasha Levin wrote:
>> On some failure paths we may attempt to free user context even
>> if it wasn't assigned yet. This will cause a NULL ptr deref
>> and a kernel BUG.
>>
>> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
>> ---
>> fs/notify/inotify/inotify_fsnotify.c | 6 ++++--
>> 1 file changed, 4 insertions(+), 2 deletions(-)
>>
>> diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c
>> index 43ab1e1..9c8187e 100644
>> --- a/fs/notify/inotify/inotify_fsnotify.c
>> +++ b/fs/notify/inotify/inotify_fsnotify.c
>> @@ -165,8 +165,10 @@ static void inotify_free_group_priv(struct fsnotify_group *group)
>> /* ideally the idr is empty and we won't hit the BUG in the callback */
>> idr_for_each(&group->inotify_data.idr, idr_callback, group);
>> idr_destroy(&group->inotify_data.idr);
>> - atomic_dec(&group->inotify_data.user->inotify_devs);
>> - free_uid(group->inotify_data.user);
>> + if (group->inotify_data.user) {
>> + atomic_dec(&group->inotify_data.user->inotify_devs);
>> + free_uid(group->inotify_data.user);
>> + }
>> }
>>
>> static void inotify_free_event(struct fsnotify_event *fsn_event)
>>
>



\
 
 \ /
  Last update: 2014-09-08 17:01    [W:2.515 / U:1.836 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site