Re: [syzbot] WARNING: zero-size vmalloc in corrupted

On Wed, Jun 23, 2021 at 6:28 PM syzbot
[off-list ref] wrote:

quoted

On Wed, 23 Jun 2021 19:19:28 +0300
Pavel Skripkin [off-list ref] wrote:

quoted

On Wed, 23 Jun 2021 02:15:23 -0700
syzbot [off-list ref] wrote:

quoted

Hello,

syzbot found the following issue on:

HEAD commit:    13311e74 Linux 5.13-rc7
git tree:       upstream
console output:
https://syzkaller.appspot.com/x/log.txt?x=15d01e58300000 kernel
config:  https://syzkaller.appspot.com/x/.config?x=42ecca11b759d96c
dashboard link:
https://syzkaller.appspot.com/bug?extid=c2f6f09fe907a838effb syz
repro:
https://syzkaller.appspot.com/x/repro.syz?x=14bb89e8300000 C
reproducer:
https://syzkaller.appspot.com/x/repro.c?x=17cc51b8300000

The issue was bisected to:

commit f9006acc8dfe59e25aa75729728ac57a8d84fc32
Author: Florian Westphal [off-list ref]
Date:   Wed Apr 21 07:51:08 2021 +0000

    netfilter: arp_tables: pass table pointer via nf_hook_ops

bisection log:
https://syzkaller.appspot.com/x/bisect.txt?x=13b88400300000 final
oops:
https://syzkaller.appspot.com/x/report.txt?x=10788400300000 console
output: https://syzkaller.appspot.com/x/log.txt?x=17b88400300000

This one is similar to previous zero-size vmalloc, I guess :)

#syz test
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
master

Hah, I didn't notice that this one is already fixed by me. But the
patch is in the media tree, it's not upstreamed yet:

https://git.linuxtv.org/media_tree.git/commit/?id=c680ed46e418e9c785d76cf44eb33bfd1e8cf3f6

So,

#syz dup: WARNING: zero-size vmalloc in dvb_dmx_init

Can't dup bug to a bug in different reporting (upstream->internal).Please dup syzbot bugs only onto syzbot bugs for the same kernel/reporting.

I think we can say:

#syz dup: WARNING in __vmalloc_node_range
https://syzkaller.appspot.com/bug?id=3c558412597cc402fd7fbb250ca30d04d46c8c60

as that was the original bug report.