Hello,
syzkaller hit the following crash on
30a7acd573899fd8b8ac39236eff6468b195ac7d
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.
C reproducer is attached
syzkaller reproducer is attached. See https://goo.gl/kgGztJ
for information about syzkaller reproducers
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: [email protected]
It will help syzbot understand when the bug is fixed. See footer for
details.
If you forward the report, please keep this part and the footer.
==================================================================
BUG: KASAN: null-ptr-deref in memcpy include/linux/string.h:344 [inline]
BUG: KASAN: null-ptr-deref in do_convert sound/core/oss/linear.c:52 [inline]
BUG: KASAN: null-ptr-deref in convert sound/core/oss/linear.c:81 [inline]
BUG: KASAN: null-ptr-deref in linear_transfer+0x634/0x900
sound/core/oss/linear.c:110
Write of size 2 at addr (null) by task syzkaller360172/7860
CPU: 0 PID: 7860 Comm: syzkaller360172 Not tainted 4.15.0-rc6+ #155
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x194/0x257 lib/dump_stack.c:53
kasan_report_error mm/kasan/report.c:349 [inline]
kasan_report+0x13b/0x340 mm/kasan/report.c:409
check_memory_region_inline mm/kasan/kasan.c:260 [inline]
check_memory_region+0x137/0x190 mm/kasan/kasan.c:267
memcpy+0x37/0x50 mm/kasan/kasan.c:303
memcpy include/linux/string.h:344 [inline]
do_convert sound/core/oss/linear.c:52 [inline]
convert sound/core/oss/linear.c:81 [inline]
linear_transfer+0x634/0x900 sound/core/oss/linear.c:110
snd_pcm_plug_write_transfer+0x22d/0x420 sound/core/oss/pcm_plugin.c:611
snd_pcm_oss_write2+0x260/0x420 sound/core/oss/pcm_oss.c:1311
snd_pcm_oss_sync1+0x1cc/0x550 sound/core/oss/pcm_oss.c:1530
snd_pcm_oss_sync+0x5b6/0x830 sound/core/oss/pcm_oss.c:1604
snd_pcm_oss_release+0x20b/0x280 sound/core/oss/pcm_oss.c:2431
__fput+0x327/0x7e0 fs/file_table.c:210
____fput+0x15/0x20 fs/file_table.c:244
task_work_run+0x199/0x270 kernel/task_work.c:113
exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0x9bb/0x1ad0 kernel/exit.c:865
do_group_exit+0x149/0x400 kernel/exit.c:968
get_signal+0x73f/0x16c0 kernel/signal.c:2335
do_signal+0x90/0x1eb0 arch/x86/kernel/signal.c:809
exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
syscall_return_slowpath arch/x86/entry/common.c:264 [inline]
do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline]
do_fast_syscall_32+0xbfd/0xf9d arch/x86/entry/common.c:389
entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129
RIP: 0023:0xf7fcac79
RSP: 002b:00000000f7f8412c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0
RAX: fffffffffffffe00 RBX: 00000000080fd024 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000080fd024
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 7860 Comm: syzkaller360172 Tainted: G B
4.15.0-rc6+ #155
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x194/0x257 lib/dump_stack.c:53
panic+0x1e4/0x41c kernel/panic.c:183
kasan_end_report+0x50/0x50 mm/kasan/report.c:176
kasan_report_error mm/kasan/report.c:356 [inline]
kasan_report+0x144/0x340 mm/kasan/report.c:409
check_memory_region_inline mm/kasan/kasan.c:260 [inline]
check_memory_region+0x137/0x190 mm/kasan/kasan.c:267
memcpy+0x37/0x50 mm/kasan/kasan.c:303
memcpy include/linux/string.h:344 [inline]
do_convert sound/core/oss/linear.c:52 [inline]
convert sound/core/oss/linear.c:81 [inline]
linear_transfer+0x634/0x900 sound/core/oss/linear.c:110
snd_pcm_plug_write_transfer+0x22d/0x420 sound/core/oss/pcm_plugin.c:611
snd_pcm_oss_write2+0x260/0x420 sound/core/oss/pcm_oss.c:1311
snd_pcm_oss_sync1+0x1cc/0x550 sound/core/oss/pcm_oss.c:1530
snd_pcm_oss_sync+0x5b6/0x830 sound/core/oss/pcm_oss.c:1604
snd_pcm_oss_release+0x20b/0x280 sound/core/oss/pcm_oss.c:2431
__fput+0x327/0x7e0 fs/file_table.c:210
____fput+0x15/0x20 fs/file_table.c:244
task_work_run+0x199/0x270 kernel/task_work.c:113
exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0x9bb/0x1ad0 kernel/exit.c:865
do_group_exit+0x149/0x400 kernel/exit.c:968
get_signal+0x73f/0x16c0 kernel/signal.c:2335
do_signal+0x90/0x1eb0 arch/x86/kernel/signal.c:809
exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
syscall_return_slowpath arch/x86/entry/common.c:264 [inline]
do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline]
do_fast_syscall_32+0xbfd/0xf9d arch/x86/entry/common.c:389
entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129
RIP: 0023:0xf7fcac79
RSP: 002b:00000000f7f8412c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0
RAX: fffffffffffffe00 RBX: 00000000080fd024 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000080fd024
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..
---
This bug is generated by a dumb bot. It may contain errors.
See https://goo.gl/tpsmEJ for details.
Direct all questions to [email protected].
syzbot will keep track of this bug report.
If you forgot to add the Reported-by tag, once the fix for this bug is
merged
into any tree, please reply to this email with:
#syz fix: exact-commit-title
If you want to test a patch for this bug, please reply with:
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and provide the patch inline or as an attachment.
To mark this as a duplicate of another syzbot report, please reply with:
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If it's a one-off invalid bug report, please reply with:
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Note: if the crash happens again, it will cause creation of a new bug
report.
Note: all commands must start from beginning of the line in the email body.
On Fri, Jan 05, 2018 at 02:58:02AM -0800, syzbot wrote:
> Hello,
>
> syzkaller hit the following crash on
> 30a7acd573899fd8b8ac39236eff6468b195ac7d
> git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
> compiler: gcc (GCC) 7.1.1 20170620
> .config is attached
> Raw console output is attached.
> C reproducer is attached
> syzkaller reproducer is attached. See https://goo.gl/kgGztJ
> for information about syzkaller reproducers
>
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: [email protected]
> It will help syzbot understand when the bug is fixed. See footer for
> details.
> If you forward the report, please keep this part and the footer.
>
> ==================================================================
> BUG: KASAN: null-ptr-deref in memcpy include/linux/string.h:344 [inline]
> BUG: KASAN: null-ptr-deref in do_convert sound/core/oss/linear.c:52 [inline]
> BUG: KASAN: null-ptr-deref in convert sound/core/oss/linear.c:81 [inline]
> BUG: KASAN: null-ptr-deref in linear_transfer+0x634/0x900
> sound/core/oss/linear.c:110
> Write of size 2 at addr (null) by task syzkaller360172/7860
>
> CPU: 0 PID: 7860 Comm: syzkaller360172 Not tainted 4.15.0-rc6+ #155
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> Call Trace:
> __dump_stack lib/dump_stack.c:17 [inline]
> dump_stack+0x194/0x257 lib/dump_stack.c:53
> kasan_report_error mm/kasan/report.c:349 [inline]
> kasan_report+0x13b/0x340 mm/kasan/report.c:409
> check_memory_region_inline mm/kasan/kasan.c:260 [inline]
> check_memory_region+0x137/0x190 mm/kasan/kasan.c:267
> memcpy+0x37/0x50 mm/kasan/kasan.c:303
> memcpy include/linux/string.h:344 [inline]
> do_convert sound/core/oss/linear.c:52 [inline]
> convert sound/core/oss/linear.c:81 [inline]
> linear_transfer+0x634/0x900 sound/core/oss/linear.c:110
> snd_pcm_plug_write_transfer+0x22d/0x420 sound/core/oss/pcm_plugin.c:611
> snd_pcm_oss_write2+0x260/0x420 sound/core/oss/pcm_oss.c:1311
> snd_pcm_oss_sync1+0x1cc/0x550 sound/core/oss/pcm_oss.c:1530
> snd_pcm_oss_sync+0x5b6/0x830 sound/core/oss/pcm_oss.c:1604
> snd_pcm_oss_release+0x20b/0x280 sound/core/oss/pcm_oss.c:2431
> __fput+0x327/0x7e0 fs/file_table.c:210
> ____fput+0x15/0x20 fs/file_table.c:244
> task_work_run+0x199/0x270 kernel/task_work.c:113
> exit_task_work include/linux/task_work.h:22 [inline]
> do_exit+0x9bb/0x1ad0 kernel/exit.c:865
> do_group_exit+0x149/0x400 kernel/exit.c:968
> get_signal+0x73f/0x16c0 kernel/signal.c:2335
> do_signal+0x90/0x1eb0 arch/x86/kernel/signal.c:809
> exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
> prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
> syscall_return_slowpath arch/x86/entry/common.c:264 [inline]
> do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline]
> do_fast_syscall_32+0xbfd/0xf9d arch/x86/entry/common.c:389
> entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129
Still reproducible even after all the fixes currently in sound/for-linus.
Eric
On Wed, 10 Jan 2018 09:08:00 +0100,
Eric Biggers wrote:
>
> On Fri, Jan 05, 2018 at 02:58:02AM -0800, syzbot wrote:
> > Hello,
> >
> > syzkaller hit the following crash on
> > 30a7acd573899fd8b8ac39236eff6468b195ac7d
> > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
> > compiler: gcc (GCC) 7.1.1 20170620
> > .config is attached
> > Raw console output is attached.
> > C reproducer is attached
> > syzkaller reproducer is attached. See https://goo.gl/kgGztJ
> > for information about syzkaller reproducers
> >
> >
> > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > Reported-by: [email protected]
> > It will help syzbot understand when the bug is fixed. See footer for
> > details.
> > If you forward the report, please keep this part and the footer.
> >
> > ==================================================================
> > BUG: KASAN: null-ptr-deref in memcpy include/linux/string.h:344 [inline]
> > BUG: KASAN: null-ptr-deref in do_convert sound/core/oss/linear.c:52 [inline]
> > BUG: KASAN: null-ptr-deref in convert sound/core/oss/linear.c:81 [inline]
> > BUG: KASAN: null-ptr-deref in linear_transfer+0x634/0x900
> > sound/core/oss/linear.c:110
> > Write of size 2 at addr (null) by task syzkaller360172/7860
> >
> > CPU: 0 PID: 7860 Comm: syzkaller360172 Not tainted 4.15.0-rc6+ #155
> > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> > Google 01/01/2011
> > Call Trace:
> > __dump_stack lib/dump_stack.c:17 [inline]
> > dump_stack+0x194/0x257 lib/dump_stack.c:53
> > kasan_report_error mm/kasan/report.c:349 [inline]
> > kasan_report+0x13b/0x340 mm/kasan/report.c:409
> > check_memory_region_inline mm/kasan/kasan.c:260 [inline]
> > check_memory_region+0x137/0x190 mm/kasan/kasan.c:267
> > memcpy+0x37/0x50 mm/kasan/kasan.c:303
> > memcpy include/linux/string.h:344 [inline]
> > do_convert sound/core/oss/linear.c:52 [inline]
> > convert sound/core/oss/linear.c:81 [inline]
> > linear_transfer+0x634/0x900 sound/core/oss/linear.c:110
> > snd_pcm_plug_write_transfer+0x22d/0x420 sound/core/oss/pcm_plugin.c:611
> > snd_pcm_oss_write2+0x260/0x420 sound/core/oss/pcm_oss.c:1311
> > snd_pcm_oss_sync1+0x1cc/0x550 sound/core/oss/pcm_oss.c:1530
> > snd_pcm_oss_sync+0x5b6/0x830 sound/core/oss/pcm_oss.c:1604
> > snd_pcm_oss_release+0x20b/0x280 sound/core/oss/pcm_oss.c:2431
> > __fput+0x327/0x7e0 fs/file_table.c:210
> > ____fput+0x15/0x20 fs/file_table.c:244
> > task_work_run+0x199/0x270 kernel/task_work.c:113
> > exit_task_work include/linux/task_work.h:22 [inline]
> > do_exit+0x9bb/0x1ad0 kernel/exit.c:865
> > do_group_exit+0x149/0x400 kernel/exit.c:968
> > get_signal+0x73f/0x16c0 kernel/signal.c:2335
> > do_signal+0x90/0x1eb0 arch/x86/kernel/signal.c:809
> > exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
> > prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
> > syscall_return_slowpath arch/x86/entry/common.c:264 [inline]
> > do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline]
> > do_fast_syscall_32+0xbfd/0xf9d arch/x86/entry/common.c:389
> > entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129
>
> Still reproducible even after all the fixes currently in sound/for-linus.
Interesting, I can't reproduce it on my VM any longer...
Takashi
On Wed, Jan 10, 2018 at 10:58:43AM +0100, Takashi Iwai wrote:
> On Wed, 10 Jan 2018 09:08:00 +0100,
> Eric Biggers wrote:
> >
> > On Fri, Jan 05, 2018 at 02:58:02AM -0800, syzbot wrote:
> > > Hello,
> > >
> > > syzkaller hit the following crash on
> > > 30a7acd573899fd8b8ac39236eff6468b195ac7d
> > > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
> > > compiler: gcc (GCC) 7.1.1 20170620
> > > .config is attached
> > > Raw console output is attached.
> > > C reproducer is attached
> > > syzkaller reproducer is attached. See https://goo.gl/kgGztJ
> > > for information about syzkaller reproducers
> > >
> > >
> > > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > > Reported-by: [email protected]
> > > It will help syzbot understand when the bug is fixed. See footer for
> > > details.
> > > If you forward the report, please keep this part and the footer.
> > >
> > > ==================================================================
> > > BUG: KASAN: null-ptr-deref in memcpy include/linux/string.h:344 [inline]
> > > BUG: KASAN: null-ptr-deref in do_convert sound/core/oss/linear.c:52 [inline]
> > > BUG: KASAN: null-ptr-deref in convert sound/core/oss/linear.c:81 [inline]
> > > BUG: KASAN: null-ptr-deref in linear_transfer+0x634/0x900
> > > sound/core/oss/linear.c:110
> > > Write of size 2 at addr (null) by task syzkaller360172/7860
> > >
> > > CPU: 0 PID: 7860 Comm: syzkaller360172 Not tainted 4.15.0-rc6+ #155
> > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> > > Google 01/01/2011
> > > Call Trace:
> > > __dump_stack lib/dump_stack.c:17 [inline]
> > > dump_stack+0x194/0x257 lib/dump_stack.c:53
> > > kasan_report_error mm/kasan/report.c:349 [inline]
> > > kasan_report+0x13b/0x340 mm/kasan/report.c:409
> > > check_memory_region_inline mm/kasan/kasan.c:260 [inline]
> > > check_memory_region+0x137/0x190 mm/kasan/kasan.c:267
> > > memcpy+0x37/0x50 mm/kasan/kasan.c:303
> > > memcpy include/linux/string.h:344 [inline]
> > > do_convert sound/core/oss/linear.c:52 [inline]
> > > convert sound/core/oss/linear.c:81 [inline]
> > > linear_transfer+0x634/0x900 sound/core/oss/linear.c:110
> > > snd_pcm_plug_write_transfer+0x22d/0x420 sound/core/oss/pcm_plugin.c:611
> > > snd_pcm_oss_write2+0x260/0x420 sound/core/oss/pcm_oss.c:1311
> > > snd_pcm_oss_sync1+0x1cc/0x550 sound/core/oss/pcm_oss.c:1530
> > > snd_pcm_oss_sync+0x5b6/0x830 sound/core/oss/pcm_oss.c:1604
> > > snd_pcm_oss_release+0x20b/0x280 sound/core/oss/pcm_oss.c:2431
> > > __fput+0x327/0x7e0 fs/file_table.c:210
> > > ____fput+0x15/0x20 fs/file_table.c:244
> > > task_work_run+0x199/0x270 kernel/task_work.c:113
> > > exit_task_work include/linux/task_work.h:22 [inline]
> > > do_exit+0x9bb/0x1ad0 kernel/exit.c:865
> > > do_group_exit+0x149/0x400 kernel/exit.c:968
> > > get_signal+0x73f/0x16c0 kernel/signal.c:2335
> > > do_signal+0x90/0x1eb0 arch/x86/kernel/signal.c:809
> > > exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
> > > prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
> > > syscall_return_slowpath arch/x86/entry/common.c:264 [inline]
> > > do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline]
> > > do_fast_syscall_32+0xbfd/0xf9d arch/x86/entry/common.c:389
> > > entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129
> >
> > Still reproducible even after all the fixes currently in sound/for-linus.
>
> Interesting, I can't reproduce it on my VM any longer...
>
No longer occurring, last occurrence was Mar 29 on commit a2601d78b77aa.
Seems to have been fixed by commit 02a5d6925cd3:
#syz fix: ALSA: pcm: Avoid potential races between OSS ioctls and read/write
The reproducer was opening /dev/dsp1, then concurrently writing to it and
calling the SNDCTL_DSP_SPEED ioctl.
- Eric
On Sun, 13 May 2018 09:36:36 +0200,
Eric Biggers wrote:
>
> On Wed, Jan 10, 2018 at 10:58:43AM +0100, Takashi Iwai wrote:
> > On Wed, 10 Jan 2018 09:08:00 +0100,
> > Eric Biggers wrote:
> > >
> > > On Fri, Jan 05, 2018 at 02:58:02AM -0800, syzbot wrote:
> > > > Hello,
> > > >
> > > > syzkaller hit the following crash on
> > > > 30a7acd573899fd8b8ac39236eff6468b195ac7d
> > > > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
> > > > compiler: gcc (GCC) 7.1.1 20170620
> > > > .config is attached
> > > > Raw console output is attached.
> > > > C reproducer is attached
> > > > syzkaller reproducer is attached. See https://goo.gl/kgGztJ
> > > > for information about syzkaller reproducers
> > > >
> > > >
> > > > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > > > Reported-by: [email protected]
> > > > It will help syzbot understand when the bug is fixed. See footer for
> > > > details.
> > > > If you forward the report, please keep this part and the footer.
> > > >
> > > > ==================================================================
> > > > BUG: KASAN: null-ptr-deref in memcpy include/linux/string.h:344 [inline]
> > > > BUG: KASAN: null-ptr-deref in do_convert sound/core/oss/linear.c:52 [inline]
> > > > BUG: KASAN: null-ptr-deref in convert sound/core/oss/linear.c:81 [inline]
> > > > BUG: KASAN: null-ptr-deref in linear_transfer+0x634/0x900
> > > > sound/core/oss/linear.c:110
> > > > Write of size 2 at addr (null) by task syzkaller360172/7860
> > > >
> > > > CPU: 0 PID: 7860 Comm: syzkaller360172 Not tainted 4.15.0-rc6+ #155
> > > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> > > > Google 01/01/2011
> > > > Call Trace:
> > > > __dump_stack lib/dump_stack.c:17 [inline]
> > > > dump_stack+0x194/0x257 lib/dump_stack.c:53
> > > > kasan_report_error mm/kasan/report.c:349 [inline]
> > > > kasan_report+0x13b/0x340 mm/kasan/report.c:409
> > > > check_memory_region_inline mm/kasan/kasan.c:260 [inline]
> > > > check_memory_region+0x137/0x190 mm/kasan/kasan.c:267
> > > > memcpy+0x37/0x50 mm/kasan/kasan.c:303
> > > > memcpy include/linux/string.h:344 [inline]
> > > > do_convert sound/core/oss/linear.c:52 [inline]
> > > > convert sound/core/oss/linear.c:81 [inline]
> > > > linear_transfer+0x634/0x900 sound/core/oss/linear.c:110
> > > > snd_pcm_plug_write_transfer+0x22d/0x420 sound/core/oss/pcm_plugin.c:611
> > > > snd_pcm_oss_write2+0x260/0x420 sound/core/oss/pcm_oss.c:1311
> > > > snd_pcm_oss_sync1+0x1cc/0x550 sound/core/oss/pcm_oss.c:1530
> > > > snd_pcm_oss_sync+0x5b6/0x830 sound/core/oss/pcm_oss.c:1604
> > > > snd_pcm_oss_release+0x20b/0x280 sound/core/oss/pcm_oss.c:2431
> > > > __fput+0x327/0x7e0 fs/file_table.c:210
> > > > ____fput+0x15/0x20 fs/file_table.c:244
> > > > task_work_run+0x199/0x270 kernel/task_work.c:113
> > > > exit_task_work include/linux/task_work.h:22 [inline]
> > > > do_exit+0x9bb/0x1ad0 kernel/exit.c:865
> > > > do_group_exit+0x149/0x400 kernel/exit.c:968
> > > > get_signal+0x73f/0x16c0 kernel/signal.c:2335
> > > > do_signal+0x90/0x1eb0 arch/x86/kernel/signal.c:809
> > > > exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
> > > > prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
> > > > syscall_return_slowpath arch/x86/entry/common.c:264 [inline]
> > > > do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline]
> > > > do_fast_syscall_32+0xbfd/0xf9d arch/x86/entry/common.c:389
> > > > entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129
> > >
> > > Still reproducible even after all the fixes currently in sound/for-linus.
> >
> > Interesting, I can't reproduce it on my VM any longer...
> >
>
> No longer occurring, last occurrence was Mar 29 on commit a2601d78b77aa.
> Seems to have been fixed by commit 02a5d6925cd3:
>
> #syz fix: ALSA: pcm: Avoid potential races between OSS ioctls and read/write
>
> The reproducer was opening /dev/dsp1, then concurrently writing to it and
> calling the SNDCTL_DSP_SPEED ioctl.
Good to hear. Yes, this should have been covered by the change.
Thanks for checking!
Takashi