Re: kernel BUG at arch/x86/mm/physaddr.c:LINE! (2)

From: Hans Verkuil
Date: Thu Apr 04 2019 - 10:51:45 EST


On 4/4/19 4:47 PM, Alexander Potapenko wrote:
> On Wed, Mar 20, 2019 at 9:35 PM syzbot
> <syzbot+6c0effb5877f6b0344e2@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>>
>> syzbot has bisected this bug to:
>>
>> commit 6d469a202ee73196d0df76025af80bd6a379e658
>> Author: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
>> Date: Sun May 14 17:07:21 2017 +0000
>>
>> Merge tag 'v4.12-rc1' into patchwork
>>
>> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12639fd7200000
>> start commit: 6d469a20 Merge tag 'v4.12-rc1' into patchwork
>> git tree: upstream
>> final crash: https://syzkaller.appspot.com/x/report.txt?x=15639fd7200000
>> console output: https://syzkaller.appspot.com/x/log.txt?x=11639fd7200000
>> kernel config: https://syzkaller.appspot.com/x/.config?x=d86f24333880b605
>> dashboard link: https://syzkaller.appspot.com/bug?extid=6c0effb5877f6b0344e2
>> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1312062b400000
>> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=131bd093400000
>>
>> Reported-by: syzbot+6c0effb5877f6b0344e2@xxxxxxxxxxxxxxxxxxxxxxxxx
>> Fixes: 6d469a20 ("Merge tag 'v4.12-rc1' into patchwork")
>>
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>
> I believe this bug is caused by vivid_vid_cap_s_selection() calling
> kfree(dev->bitmap_cap).
> This makes little sense, as dev->bitmap_cap seems to be allocated
> using vzalloc().
>

Yup, that should be vfree. There was a similar problem with bitmap_out that
I fixed, but it looks I missed this one. Can you make a patch?

Thanks,

Hans