syzbot

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BUG: KMSAN: uninit-value in do_update_region+0x4c1/0xc10 drivers/tty/vt/vt.c:671
CPU: 0 PID: 25036 Comm: syz-executor.0 Not tainted 5.8.0-rc5-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+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 do_update_region+0x4c1/0xc10 drivers/tty/vt/vt.c:671
 redraw_screen+0x17a4/0x2980 drivers/tty/vt/vt.c:1029
 vc_do_resize+0x36a8/0x38f0 drivers/tty/vt/vt.c:1314
 vc_resize+0xc3/0xe0 drivers/tty/vt/vt.c:1334
 fbcon_modechanged+0xdc1/0x1320 drivers/video/fbdev/core/fbcon.c:2990
 fbcon_update_vcs+0x86/0xa0 drivers/video/fbdev/core/fbcon.c:3048
 fb_set_var+0x1420/0x1850 drivers/video/fbdev/core/fbmem.c:1056
 do_fb_ioctl+0xc00/0x1150 drivers/video/fbdev/core/fbmem.c:1109
 fb_ioctl+0x1e4/0x210 drivers/video/fbdev/core/fbmem.c:1185
 vfs_ioctl fs/ioctl.c:48 [inline]
 ksys_ioctl fs/ioctl.c:753 [inline]
 __do_sys_ioctl fs/ioctl.c:762 [inline]
 __se_sys_ioctl+0x319/0x4d0 fs/ioctl.c:760
 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:760
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45d5b9
Code: Bad RIP value.
RSP: 002b:00007f5fc694ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000000e200 RCX: 000000000045d5b9
RDX: 00000000200001c0 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c
R13: 000000000169fb6f R14: 00007f5fc694b9c0 R15: 000000000118cf4c

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
 kmsan_memcpy_memmove_metadata+0x272/0x2e0 mm/kmsan/kmsan.c:247
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:267
 __msan_memcpy+0x43/0x50 mm/kmsan/kmsan_instr.c:116
 scr_memcpyw include/linux/vt_buffer.h:49 [inline]
 vc_do_resize+0x267e/0x38f0 drivers/tty/vt/vt.c:1280
 vc_resize+0xc3/0xe0 drivers/tty/vt/vt.c:1334
 fbcon_modechanged+0xdc1/0x1320 drivers/video/fbdev/core/fbcon.c:2990
 fbcon_update_vcs+0x86/0xa0 drivers/video/fbdev/core/fbcon.c:3048
 fb_set_var+0x1420/0x1850 drivers/video/fbdev/core/fbmem.c:1056
 do_fb_ioctl+0xc00/0x1150 drivers/video/fbdev/core/fbmem.c:1109
 fb_ioctl+0x1e4/0x210 drivers/video/fbdev/core/fbmem.c:1185
 vfs_ioctl fs/ioctl.c:48 [inline]
 ksys_ioctl fs/ioctl.c:753 [inline]
 __do_sys_ioctl fs/ioctl.c:762 [inline]
 __se_sys_ioctl+0x319/0x4d0 fs/ioctl.c:760
 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:760
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2839 [inline]
 __kmalloc_node+0xe70/0x1280 mm/slub.c:3959
 kmalloc_node include/linux/slab.h:578 [inline]
 kvmalloc_node+0x205/0x490 mm/util.c:574
 kvmalloc include/linux/mm.h:753 [inline]
 xt_alloc_table_info+0xda/0x1b0 net/netfilter/x_tables.c:1176
 do_replace net/ipv4/netfilter/ip_tables.c:1125 [inline]
 do_ipt_set_ctl+0x4bc/0xae0 net/ipv4/netfilter/ip_tables.c:1672
 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
 nf_setsockopt+0x578/0x5d0 net/netfilter/nf_sockopt.c:115
 ip_setsockopt+0x355/0x3d0 net/ipv4/ip_sockglue.c:1319
 tcp_setsockopt+0x1d7/0x200 net/ipv4/tcp.c:3334
 sock_common_setsockopt+0x136/0x170 net/core/sock.c:3262
 __sys_setsockopt+0x9c8/0xae0 net/socket.c:2127
 __do_sys_setsockopt net/socket.c:2143 [inline]
 __se_sys_setsockopt+0xdd/0x100 net/socket.c:2140
 __x64_sys_setsockopt+0x62/0x80 net/socket.c:2140
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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