divide error in vivid_vid_cap_s_dv_timings

From: syzbot
Date: Mon Oct 29 2018 - 13:13:08 EST


Hello,

syzbot found the following crash on:

HEAD commit: b179f0826c6a Add linux-next specific files for 20181029
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=175ea9c5400000
kernel config: https://syzkaller.appspot.com/x/.config?x=6b2b22387bad67fc
dashboard link: https://syzkaller.appspot.com/bug?extid=57c3d83d71187054d56f
compiler: gcc (GCC) 8.0.1 20180413 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+57c3d83d71187054d56f@xxxxxxxxxxxxxxxxxxxxxxxxx

divide error: 0000 [#1] PREEMPT SMP KASAN
netlink: 20 bytes leftover after parsing attributes in process `syz-executor5'.
CPU: 0 PID: 26335 Comm: syz-executor2 Not tainted 4.19.0-next-20181029+ #100
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:valid_cvt_gtf_timings drivers/media/platform/vivid/vivid-vid-cap.c:1633 [inline]
RIP: 0010:vivid_vid_cap_s_dv_timings+0x60e/0x11e0 drivers/media/platform/vivid/vivid-vid-cap.c:1664
Code: c6 84 c9 0f 95 c1 40 84 ce 0f 85 ce 0a 00 00 83 e0 07 38 c2 0f 9e c1 84 d2 0f 95 c0 84 c1 0f 85 b9 0a 00 00 48 8b 43 14 31 d2 <41> f7 f7 48 ba 00 00 00 00 00 fc ff df 4c 8d 7b 40 89 85 64 ff ff
RSP: 0018:ffff880180caf630 EFLAGS: 00010246
RAX: 0000000002000000 RBX: ffff8801ce323700 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8801ce323714
RBP: ffff880180caf6f0 R08: 0000000000000001 R09: ffffed003971a024
R10: ffffed003971a024 R11: ffff8801cb8d0123 R12: ffff8801cb8d0080
R13: 1ffff10030195ecd R14: 0000000000000000 R15: 0000000000000000
FS: 00007f3d49d6e700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000727e4c CR3: 00000001d9174000 CR4: 00000000001426f0
Call Trace:
vidioc_s_dv_timings+0xa4/0xc0 drivers/media/platform/vivid/vivid-core.c:323
v4l_stub_s_dv_timings+0x4f/0x60 drivers/media/v4l2-core/v4l2-ioctl.c:2581
__video_do_ioctl+0x519/0xf00 drivers/media/v4l2-core/v4l2-ioctl.c:2833
kobject: 'loop5' (00000000a1276308): kobject_uevent_env
video_usercopy+0x5c1/0x1750 drivers/media/v4l2-core/v4l2-ioctl.c:3013
kobject: 'loop5' (00000000a1276308): fill_kobj_path: path = '/devices/virtual/block/loop5'
netlink: 20 bytes leftover after parsing attributes in process `syz-executor5'.
kobject: 'loop5' (00000000a1276308): kobject_uevent_env
video_ioctl2+0x2c/0x33 drivers/media/v4l2-core/v4l2-ioctl.c:3057
v4l2_ioctl+0x154/0x1b0 drivers/media/v4l2-core/v4l2-dev.c:364
kobject: 'loop5' (00000000a1276308): fill_kobj_path: path = '/devices/virtual/block/loop5'
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:501 [inline]
do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:688
netlink: 20 bytes leftover after parsing attributes in process `syz-executor5'.
ksys_ioctl+0xa9/0xd0 fs/ioctl.c:705
__do_sys_ioctl fs/ioctl.c:712 [inline]
__se_sys_ioctl fs/ioctl.c:710 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
kobject: 'loop5' (00000000a1276308): kobject_uevent_env
kobject: 'loop5' (00000000a1276308): fill_kobj_path: path = '/devices/virtual/block/loop5'
entry_SYSCALL_64_after_hwframe+0x49/0xbe
netlink: 20 bytes leftover after parsing attributes in process `syz-executor5'.
RIP: 0033:0x457569
Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f3d49d6dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 0000000020000040 RSI: 00000000c0845657 RDI: 0000000000000003
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3d49d6e6d4
kobject: 'loop5' (00000000a1276308): kobject_uevent_env
R13: 00000000004c1e32 R14: 00000000004d2e40 R15: 00000000ffffffff
Modules linked in:
---[ end trace c59f37d57fa3eae0 ]---
kobject: 'loop5' (00000000a1276308): fill_kobj_path: path = '/devices/virtual/block/loop5'
RIP: 0010:valid_cvt_gtf_timings drivers/media/platform/vivid/vivid-vid-cap.c:1633 [inline]
RIP: 0010:vivid_vid_cap_s_dv_timings+0x60e/0x11e0 drivers/media/platform/vivid/vivid-vid-cap.c:1664
kobject: 'loop4' (00000000e1a0902a): kobject_uevent_env
kobject: 'loop4' (00000000e1a0902a): fill_kobj_path: path = '/devices/virtual/block/loop4'
Code: c6 84 c9 0f 95 c1 40 84 ce 0f 85 ce 0a 00 00 83 e0 07 38 c2 0f 9e c1 84 d2 0f 95 c0 84 c1 0f 85 b9 0a 00 00 48 8b 43 14 31 d2 <41> f7 f7 48 ba 00 00 00 00 00 fc ff df 4c 8d 7b 40 89 85 64 ff ff
kobject: 'loop5' (00000000a1276308): kobject_uevent_env
kobject: 'kvm' (0000000010b8511c): kobject_uevent_env
kobject: 'kvm' (0000000010b8511c): fill_kobj_path: path = '/devices/virtual/misc/kvm'
kobject: 'loop5' (00000000a1276308): fill_kobj_path: path = '/devices/virtual/block/loop5'
RSP: 0018:ffff880180caf630 EFLAGS: 00010246
RAX: 0000000002000000 RBX: ffff8801ce323700 RCX: 0000000000000001
kobject: 'loop1' (00000000c8fe2913): kobject_uevent_env
kobject: 'kvm' (0000000010b8511c): kobject_uevent_env
kobject: 'loop1' (00000000c8fe2913): fill_kobj_path: path = '/devices/virtual/block/loop1'
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8801ce323714
kobject: 'kvm' (0000000010b8511c): fill_kobj_path: path = '/devices/virtual/misc/kvm'
kobject: 'kvm' (0000000010b8511c): kobject_uevent_env
kobject: 'kvm' (0000000010b8511c): fill_kobj_path: path = '/devices/virtual/misc/kvm'
RBP: ffff880180caf6f0 R08: 0000000000000001 R09: ffffed003971a024
kobject: 'kvm' (0000000010b8511c): kobject_uevent_env
kobject: 'kvm' (0000000010b8511c): fill_kobj_path: path = '/devices/virtual/misc/kvm'
R10: ffffed003971a024 R11: ffff8801cb8d0123 R12: ffff8801cb8d0080
R13: 1ffff10030195ecd R14: 0000000000000000 R15: 0000000000000000
FS: 00007f3d49d6e700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
kobject: 'loop4' (00000000e1a0902a): kobject_uevent_env
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
kobject: 'loop4' (00000000e1a0902a): fill_kobj_path: path = '/devices/virtual/block/loop4'
CR2: 00007fd3f654b000 CR3: 00000001d9174000 CR4: 00000000001426f0


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