Hello,

syzkaller hit the following crash on ad036b63ee57df9ab802a4eb20cbbbec66aa4520 git://git.cmpxchg.org/linux-mmots.git/master compiler: gcc (GCC) 7.1.1 20170620 .config is attached Raw console output is attached. Unfortunately, I don't have any reproducer for this bug yet.

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============================= WARNING: suspicious RCU usage 4.15.0-rc6-mm1+ #50 Not tainted kauditd_printk_skb: 75 callbacks suppressed audit: type=1326 audit(1514976425.195:283): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=6814 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ac9 code=0x7ffc0000 audit: type=1326 audit(1514976425.196:284): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=6814 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=8 compat=0 ip=0x452ac9 code=0x7ffc0000 audit: type=1326 audit(1514976425.196:285): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=6814 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ac9 code=0x7ffc0000 audit: type=1326 audit(1514976425.196:286): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=6814 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=9 compat=0 ip=0x452ac9 code=0x7ffc0000 audit: type=1326 audit(1514976425.199:287): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=6814 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ac9 code=0x7ffc0000 audit: type=1326 audit(1514976425.202:288): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=6814 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=257 compat=0 ip=0x452ac9 code=0x7ffc0000 audit: type=1326 audit(1514976425.203:289): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=6814 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ac9 code=0x7ffc0000 audit: type=1326 audit(1514976425.203:290): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=6814 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ac9 code=0x7ffc0000 audit: type=1326 audit(1514976425.240:291): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=6814 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=317 compat=0 ip=0x452ac9 code=0x7ffc0000 audit: type=1326 audit(1514976425.240:292): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=6814 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ac9 code=0x7ffc0000 WARNING: CPU: 0 PID: 6848 at sound/core/pcm_lib.c:1635 snd_pcm_hw_param_first+0x289/0x690 sound/core/pcm_lib.c:1635 Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 6848 Comm: syz-executor4 Not tainted 4.15.0-rc6-mm1+ #50 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+0x137/0x198 lib/dump_stack.c:53 panic+0x1e4/0x41c kernel/panic.c:183 __warn+0x1dc/0x200 kernel/panic.c:547 report_bug+0x211/0x2d0 lib/bug.c:184 fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178 fixup_bug arch/x86/kernel/traps.c:247 [inline] do_error_trap+0x249/0x290 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315 invalid_op+0x22/0x40 arch/x86/entry/entry_64.S:1079 RIP: 0010:snd_pcm_hw_param_first+0x289/0x690 sound/core/pcm_lib.c:1635 RSP: 0018:ffff8801d5367950 EFLAGS: 00010216 RAX: 0000000000010000 RBX: ffff8801c18936c0 RCX: ffffffff83b45549 RDX: 00000000000018c6 RSI: ffffc90003dcc000 RDI: ffff8801c18936e8 RBP: ffff8801d53679a0 R08: ffffed003aa6ce99 R09: ffff8801d53674c0 R10: 0000000000000001 R11: ffffed003aa6ce98 R12: 000000000000000d R13: 00000000ffffffea R14: 0000000000000005 R15: 0000000000002000 snd_pcm_hw_param_near.constprop.28+0x66e/0x790 sound/core/oss/pcm_oss.c:457 snd_pcm_oss_change_params+0x1513/0x3210 sound/core/oss/pcm_oss.c:969 snd_pcm_oss_make_ready+0xaa/0x130 sound/core/oss/pcm_oss.c:1128 snd_pcm_oss_read1 sound/core/oss/pcm_oss.c:1436 [inline] snd_pcm_oss_read+0x161/0x5c0 sound/core/oss/pcm_oss.c:2623 __vfs_read+0xef/0x730 fs/read_write.c:411 vfs_read+0x11e/0x350 fs/read_write.c:447 SYSC_read fs/read_write.c:573 [inline] SyS_read+0xd4/0x1a0 fs/read_write.c:566 entry_SYSCALL_64_fastpath+0x23/0x9a RIP: 0033:0x452ac9 RSP: 002b:00007fc02c6cac58 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007fc02c6cb700 RCX: 0000000000452ac9 RDX: 0000000000000099 RSI: 0000000020aebf67 RDI: 0000000000000013 RBP: 0000000000a2f870 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 R13: 0000000000a2f7ef R14: 00007fc02c6cb9c0 R15: 0000000000000002 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled

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