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BUG: KASAN: null-ptr-deref in memset include/linux/string.h:365 [inline]
BUG: KASAN: null-ptr-deref in video_get_user drivers/media/v4l2-core/v4l2-ioctl.c:3038 [inline]
BUG: KASAN: null-ptr-deref in video_usercopy+0x30f/0xd80 drivers/media/v4l2-core/v4l2-ioctl.c:3117
Write of size 512 at addr 0000000000000000 by task syz-executor.0/8037

CPU: 1 PID: 8037 Comm: syz-executor.0 Not tainted 5.5.0-rc1-syzkaller #0
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+0x12d/0x187 lib/dump_stack.c:118
 __kasan_report.cold.11+0x5/0x3a mm/kasan/report.c:510
 kasan_report+0x12/0x20 mm/kasan/common.c:639
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x153/0x1d0 mm/kasan/generic.c:192
 memset+0x23/0x40 mm/kasan/common.c:108
 memset include/linux/string.h:365 [inline]
 video_get_user drivers/media/v4l2-core/v4l2-ioctl.c:3038 [inline]
 video_usercopy+0x30f/0xd80 drivers/media/v4l2-core/v4l2-ioctl.c:3117
 video_ioctl2+0x10/0x12 drivers/media/v4l2-core/v4l2-ioctl.c:3181
 v4l2_ioctl+0x191/0x210 drivers/media/v4l2-core/v4l2-dev.c:360
 vfs_ioctl fs/ioctl.c:47 [inline]
 file_ioctl fs/ioctl.c:545 [inline]
 do_vfs_ioctl+0x196/0x1190 fs/ioctl.c:732
 ksys_ioctl+0x62/0x90 fs/ioctl.c:749
 __do_sys_ioctl fs/ioctl.c:756 [inline]
 __se_sys_ioctl fs/ioctl.c:754 [inline]
 __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:754
 do_syscall_64+0xca/0x5f0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45af49
Code: ad b6 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f76a7a27c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045af49
RDX: 0000000000000000 RSI: 0000001002008914 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f76a7a286d4
R13: 00000000004c2837 R14: 00000000004d8b30 R15: 00000000ffffffff
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