[syzbot] upstream build error (17)

[syzbot] upstream build error (17)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    3e732ebf7316 Merge tag 'for_linus' of git://git.kernel.org..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10ca0687700000
kernel config:  https://syzkaller.appspot.com/x/.config?x=eba855fbe3373b4f
dashboard link: https://syzkaller.appspot.com/bug?extid=6b36bab98e240873fd5a
compiler:       Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6b36bab98e240873fd5a@syzkaller.appspotmail.com

arch/x86/kvm/emulate.c:3332:5: error: stack frame size (2552) exceeds limit (2048) in function 'emulator_task_switch' [-Werror,-Wframe-larger-than]
sound/usb/mixer_s1810c.c:543:5: error: stack frame size (2072) exceeds limit (2048) in function 'snd_sc1810_init_mixer' [-Werror,-Wframe-larger-than]
drivers/block/loop.c:1524:12: error: stack frame size (2648) exceeds limit (2048) in function 'lo_ioctl' [-Werror,-Wframe-larger-than]
crypto/ecc.c:1362:6: error: stack frame size (3640) exceeds limit (2048) in function 'ecc_point_mult_shamir' [-Werror,-Wframe-larger-than]
crypto/ecc.c:1280:13: error: stack frame size (3832) exceeds limit (2048) in function 'ecc_point_mult' [-Werror,-Wframe-larger-than]
fs/ocfs2/dlm/dlmdomain.c:2101:19: error: stack frame size (2104) exceeds limit (2048) in function 'dlm_register_domain' [-Werror,-Wframe-larger-than]
net/qrtr/ns.c:661:13: error: stack frame size (3096) exceeds limit (2048) in function 'qrtr_ns_worker' [-Werror,-Wframe-larger-than]

---
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Re: [syzbot] upstream build error (17)

[Paolo Bonzini]

On 4/6/22 18:20, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    3e732ebf7316 Merge tag 'for_linus' of git://git.kernel.org..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=10ca0687700000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=eba855fbe3373b4f
> dashboard link: https://syzkaller.appspot.com/bug?extid=6b36bab98e240873fd5a
> compiler:       Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+6b36bab98e240873fd5a@syzkaller.appspotmail.com
> 
> arch/x86/kvm/emulate.c:3332:5: error: stack frame size (2552) exceeds limit (2048) in function 'emulator_task_switch' [-Werror,-Wframe-larger-than]
> drivers/block/loop.c:1524:12: error: stack frame size (2648) exceeds limit (2048) in function 'lo_ioctl' [-Werror,-Wframe-larger-than]

I spot-checked these two and the stack frame is just 144 and 320 bytes 
respectively on a normal compile.  This is probably just the effect of 
some of the sanitizer options.

Paolo

Re: [syzbot] upstream build error (17)

[Nick Desaulniers]

On Wed, Apr 6, 2022 at 10:33 AM Paolo Bonzini <pbonzini@redhat.com> wrote:
>
> On 4/6/22 18:20, syzbot wrote:
> > Hello,
> >
> > syzbot found the following issue on:
> >
> > HEAD commit:    3e732ebf7316 Merge tag 'for_linus' of git://git.kernel.org..
> > git tree:       upstream
> > console output: https://syzkaller.appspot.com/x/log.txt?x=10ca0687700000
> > kernel config:  https://syzkaller.appspot.com/x/.config?x=eba855fbe3373b4f
> > dashboard link: https://syzkaller.appspot.com/bug?extid=6b36bab98e240873fd5a
> > compiler:       Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
> >
> > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > Reported-by: syzbot+6b36bab98e240873fd5a@syzkaller.appspotmail.com
> >
> > arch/x86/kvm/emulate.c:3332:5: error: stack frame size (2552) exceeds limit (2048) in function 'emulator_task_switch' [-Werror,-Wframe-larger-than]
> > drivers/block/loop.c:1524:12: error: stack frame size (2648) exceeds limit (2048) in function 'lo_ioctl' [-Werror,-Wframe-larger-than]
>
> I spot-checked these two and the stack frame is just 144 and 320 bytes
> respectively on a normal compile.  This is probably just the effect of
> some of the sanitizer options.

Yep.
$ wget -q https://syzkaller.appspot.com/x/.config\?x\=eba855fbe3373b4f
-O - | grep CONFIG_KASAN=y
CONFIG_KASAN=y
https://github.com/ClangBuiltLinux/linux/issues/39 (our oldest still-open issue)
-- 
Thanks,
~Nick Desaulniers

Re: [syzbot] upstream build error (17)

[Dmitry Vyukov]

On Wed, 6 Apr 2022 at 20:26, Nick Desaulniers <ndesaulniers@google.com> wrote:
>
> On Wed, Apr 6, 2022 at 10:33 AM Paolo Bonzini <pbonzini@redhat.com> wrote:
> >
> > On 4/6/22 18:20, syzbot wrote:
> > > Hello,
> > >
> > > syzbot found the following issue on:
> > >
> > > HEAD commit:    3e732ebf7316 Merge tag 'for_linus' of git://git.kernel.org..
> > > git tree:       upstream
> > > console output: https://syzkaller.appspot.com/x/log.txt?x=10ca0687700000
> > > kernel config:  https://syzkaller.appspot.com/x/.config?x=eba855fbe3373b4f
> > > dashboard link: https://syzkaller.appspot.com/bug?extid=6b36bab98e240873fd5a
> > > compiler:       Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
> > >
> > > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > > Reported-by: syzbot+6b36bab98e240873fd5a@syzkaller.appspotmail.com
> > >
> > > arch/x86/kvm/emulate.c:3332:5: error: stack frame size (2552) exceeds limit (2048) in function 'emulator_task_switch' [-Werror,-Wframe-larger-than]
> > > drivers/block/loop.c:1524:12: error: stack frame size (2648) exceeds limit (2048) in function 'lo_ioctl' [-Werror,-Wframe-larger-than]
> >
> > I spot-checked these two and the stack frame is just 144 and 320 bytes
> > respectively on a normal compile.  This is probably just the effect of
> > some of the sanitizer options.
>
> Yep.
> $ wget -q https://syzkaller.appspot.com/x/.config\?x\=eba855fbe3373b4f
> -O - | grep CONFIG_KASAN=y
> CONFIG_KASAN=y
> https://github.com/ClangBuiltLinux/linux/issues/39 (our oldest still-open issue)


The issue is due to:

commit b9080ba4a6ec56447f263082825a4fddb873316b
Date:   Wed Mar 23 12:21:10 2022 +0100
    x86/defconfig: Enable WERROR

Marco has disabled it in syzbot configs:
https://github.com/google/syzkaller/commit/53c67432e69b0df4ff64448b944cbffaecec20f4

#syz invalid