Hello,

syzbot found the following crash on:

HEAD commit: fff75eb2a08c Merge tag 'errseq-v4.17' of git://git.kernel.o... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?id=6530078334779392 kernel config: https://syzkaller.appspot.com/x/.config?id=6493557782959164711 dashboard link: https://syzkaller.appspot.com/bug?extid=1dac3a4f6bc9c1c675d4 compiler: gcc (GCC) 8.0.1 20180413 (experimental) userspace arch: i386 syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?id=5691583680741376

IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+1dac3a4f6bc9c1c675d4@syzkaller.appspotmail.com

random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) IPVS: ftp: loaded support on port[0] = 21 WARNING: CPU: 1 PID: 4520 at sound/core/pcm_lib.c:2057 pcm_sanity_check sound/core/pcm_lib.c:2057 [inline] WARNING: CPU: 1 PID: 4520 at sound/core/pcm_lib.c:2057 __snd_pcm_lib_xfer+0x7c3/0x1d10 sound/core/pcm_lib.c:2122 Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 4520 Comm: syz-executor0 Not tainted 4.17.0-rc3+ #52 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 panic+0x22f/0x4de kernel/panic.c:184 __warn.cold.8+0x163/0x1b3 kernel/panic.c:536 report_bug+0x252/0x2d0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_error_trap+0x1de/0x490 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992 RIP: 0010:pcm_sanity_check sound/core/pcm_lib.c:2057 [inline] RIP: 0010:__snd_pcm_lib_xfer+0x7c3/0x1d10 sound/core/pcm_lib.c:2122 RSP: 0018:ffff8801d97b7898 EFLAGS: 00010293 RAX: ffff8801ad00e0c0 RBX: ffff8801d965e100 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff85c3d333 RDI: ffff8801d965e418 RBP: ffff8801d97b7b38 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000000 R12: ffffffff884945c0 R13: 0000000000000000 R14: ffff8801d965e100 R15: ffff8801cdd2c940 snd_pcm_lib_readv include/sound/pcm.h:1113 [inline] snd_pcm_ioctl_xfern_compat+0x266/0x330 sound/core/pcm_compat.c:448 snd_pcm_ioctl_compat+0xc96/0x1c90 sound/core/pcm_compat.c:716 __do_compat_sys_ioctl fs/compat_ioctl.c:1461 [inline] __se_compat_sys_ioctl fs/compat_ioctl.c:1407 [inline] __ia32_compat_sys_ioctl+0x221/0x640 fs/compat_ioctl.c:1407 do_syscall_32_irqs_on arch/x86/entry/common.c:323 [inline] do_fast_syscall_32+0x345/0xf9b arch/x86/entry/common.c:394 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f51cb9 RSP: 002b:00000000ffafd6ac EFLAGS: 00000282 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000800c4153 RDX: 0000000020000040 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 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 bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com.

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: #syz test: git://repo/address.git branch and provide the patch inline or as an attachment. To mark this as a duplicate of another syzbot report, please reply with: #syz dup: exact-subject-of-another-report If it's a one-off invalid bug report, please reply with: #syz invalid 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.