lkml.org 
[lkml]   [2020]   [Sep]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] net: bluetooth: Fix null pointer dereference in hci_event_packet()
On Thu, Sep 10, 2020 at 10:04:24AM +0530, Anmol Karn wrote:
> Prevent hci_phy_link_complete_evt() from dereferencing 'hcon->amp_mgr'
> as NULL. Fix it by adding pointer check for it.
>
> Reported-and-tested-by: syzbot+0bef568258653cff272f@syzkaller.appspotmail.com
> Link: https://syzkaller.appspot.com/bug?extid=0bef568258653cff272f
> Signed-off-by: Anmol Karn <anmol.karan123@gmail.com>
> ---
> net/bluetooth/hci_event.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> index 4b7fc430793c..871e16804433 100644
> --- a/net/bluetooth/hci_event.c
> +++ b/net/bluetooth/hci_event.c
> @@ -4936,6 +4936,11 @@ static void hci_phy_link_complete_evt(struct hci_dev *hdev,
> return;
> }
>
> + if (IS_ERR_OR_NULL(hcon->amp_mgr)) {
> + hci_dev_unlock(hdev);
> + return;
> + }
> +

In patches that fix a NULL pointer dereference, please include a brief
explanation of why the pointer can be NULL, including what it means
semantically; and why the proposed change is the best fix for the problem.

Also, why IS_ERR_OR_NULL()?

- Eric

\
 
 \ /
  Last update: 2020-09-10 07:07    [W:0.088 / U:0.736 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site