Re: [syzbot] UBSAN: shift-out-of-bounds in xfrm_get_default

[syzbot]

> On 8/30/21 23:19, syzbot wrote:
>> Hello,
>> 
>> syzbot found the following issue on:
>> 
>> HEAD commit:    eaf2aaec0be4 Merge tag 'wireless-drivers-next-2021-08-29' ..
>> git tree:       net-next
>> console output: https://syzkaller.appspot.com/x/log.txt?x=1219326d300000
>> kernel config:  https://syzkaller.appspot.com/x/.config?x=d2f9d4c9ff8c5ae7
>> dashboard link: https://syzkaller.appspot.com/bug?extid=b2be9dd8ca6f6c73ee2d
>> compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1
>> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11e6e3a9300000
>> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10de8a6d300000
>> 
>> The issue was bisected to:
>> 
>> commit 2d151d39073aff498358543801fca0f670fea981
>> Author: Steffen Klassert <steffen.klassert@xxxxxxxxxxx>
>> Date:   Sun Jul 18 07:11:06 2021 +0000
>> 
>>      xfrm: Add possibility to set the default to block if we have no policy
>> 
>> bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=114523fe300000
>> final oops:     https://syzkaller.appspot.com/x/report.txt?x=134523fe300000
>> console output: https://syzkaller.appspot.com/x/log.txt?x=154523fe300000
>> 
>> IMPORTANT: if you fix the issue, please add the following tag to the commit:
>> Reported-by: syzbot+b2be9dd8ca6f6c73ee2d@xxxxxxxxxxxxxxxxxxxxxxxxx
>> Fixes: 2d151d39073a ("xfrm: Add possibility to set the default to block if we have no policy")
>> 
>> netlink: 172 bytes leftover after parsing attributes in process `syz-executor354'.
>> ================================================================================
>> UBSAN: shift-out-of-bounds in net/xfrm/xfrm_user.c:2010:49
>> shift exponent 224 is too large for 32-bit type 'int'
>
>
> #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git

want 2 args (repo, branch), got 3

>
>
>
>
> With regards,
> Pavel Skripkin