------------[ cut here ]------------ unsafe follow_pfn usage WARNING: CPU: 0 PID: 30600 at mm/memory.c:4826 unsafe_follow_pfn+0x20f/0x260 mm/memory.c:4826 Modules linked in: CPU: 0 PID: 30600 Comm: syz-executor.0 Tainted: G U 5.12.0-next-20210506-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:unsafe_follow_pfn+0x20f/0x260 mm/memory.c:4826 Code: 8b 7c 24 20 49 89 6d 00 e8 1e 73 6e 07 e9 30 ff ff ff e8 64 a4 ca ff 48 c7 c7 a0 46 76 89 c6 05 7b dc 0a 0c 01 e8 e4 6d 2a 07 <0f> 0b e9 71 fe ff ff 41 bc ea ff ff ff e9 06 ff ff ff e8 1a 92 0f RSP: 0018:ffffc90002a9f658 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 1ffff92000553ecb RCX: 0000000000000000 RDX: 0000000000040000 RSI: ffffffff815ccd25 RDI: fffff52000553ebd RBP: ffff888037229c60 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815c6b8e R11: 0000000000000000 R12: 0000000021000000 R13: ffff888077e18010 R14: 0000000000000000 R15: 0000000000000110 FS: 00007f46d5f54700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a5b0bd2b78 CR3: 000000002bffe000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: get_vaddr_frames+0x337/0x600 drivers/media/common/videobuf2/frame_vector.c:72 vb2_create_framevec+0x55/0xc0 drivers/media/common/videobuf2/videobuf2-memops.c:50 vb2_vmalloc_get_userptr+0xce/0x4c0 drivers/media/common/videobuf2/videobuf2-vmalloc.c:90 __prepare_userptr+0x342/0x15f0 drivers/media/common/videobuf2/videobuf2-core.c:1128 __buf_prepare+0x635/0x7d0 drivers/media/common/videobuf2/videobuf2-core.c:1367 vb2_core_qbuf+0xa9d/0x11c0 drivers/media/common/videobuf2/videobuf2-core.c:1658 vb2_qbuf+0x135/0x1a0 drivers/media/common/videobuf2/videobuf2-v4l2.c:820 vb2_ioctl_qbuf+0xfb/0x140 drivers/media/common/videobuf2/videobuf2-v4l2.c:1050 v4l_qbuf drivers/media/v4l2-core/v4l2-ioctl.c:2027 [inline] v4l_qbuf+0x92/0xc0 drivers/media/v4l2-core/v4l2-ioctl.c:2021 __video_do_ioctl+0xb94/0xe20 drivers/media/v4l2-core/v4l2-ioctl.c:2951 video_usercopy+0x253/0x1300 drivers/media/v4l2-core/v4l2-ioctl.c:3297 v4l2_ioctl+0x1b3/0x250 drivers/media/v4l2-core/v4l2-dev.c:366 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665f9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f46d5f54188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 00000000004665f9 RDX: 0000000020000140 RSI: 00000000c058560f RDI: 0000000000000004 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008 R13: 00007ffe145a7d5f R14: 00007f46d5f54300 R15: 0000000000022000