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BUG: KASAN: user-memory-access in memset include/linux/string.h:330 [inline]
BUG: KASAN: user-memory-access in bitmap_zero include/linux/bitmap.h:218 [inline]
BUG: KASAN: user-memory-access in n_tty_set_termios+0x106/0xe80 drivers/tty/n_tty.c:1784
Write of size 512 at addr 0000000000001060 by task syz-executor2/14941

CPU: 1 PID: 14941 Comm: syz-executor2 Not tainted 4.19.0-rc6-next-20181005+ #88
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+0x1d3/0x2c4 lib/dump_stack.c:113
 kasan_report_error mm/kasan/report.c:352 [inline]
 kasan_report.cold.9+0x6d/0x309 mm/kasan/report.c:412
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
 memset+0x23/0x40 mm/kasan/kasan.c:285
 memset include/linux/string.h:330 [inline]
 bitmap_zero include/linux/bitmap.h:218 [inline]
 n_tty_set_termios+0x106/0xe80 drivers/tty/n_tty.c:1784
 tty_set_termios+0x7a0/0xac0 drivers/tty/tty_ioctl.c:341
 set_termios+0x41e/0x7d0 drivers/tty/tty_ioctl.c:414
 tty_mode_ioctl+0x53e/0xb40 drivers/tty/tty_ioctl.c:747
 n_tty_ioctl_helper+0x54/0x3b0 drivers/tty/tty_ioctl.c:940
 n_tty_ioctl+0x54/0x360 drivers/tty/n_tty.c:2450
 tty_ioctl+0x5ad/0x1820 drivers/tty/tty_io.c:2660
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702
 __do_sys_ioctl fs/ioctl.c:709 [inline]
 __se_sys_ioctl fs/ioctl.c:707 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457579
Code: 1d b4 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 eb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f5f140b1c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457579
RDX: 0000000020000040 RSI: 0000000000005403 RDI: 0000000000000006
RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5f140b26d4
R13: 00000000004c0dc6 R14: 00000000004d17e8 R15: 00000000ffffffff
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