audit: type=1400 audit(1520533936.385:8): avc:  denied  { map } for  pid=4237 comm="syz-execprog" path="/root/syzkaller-shm555629545" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:file_t:s0 tclass=file permissive=1
IPVS: ftp: loaded support on port[0] = 21
==================================================================
BUG: KASAN: stack-out-of-bounds in memcpy include/linux/string.h:345 [inline]
BUG: KASAN: stack-out-of-bounds in rdma_resolve_addr+0x12e/0x26c0 drivers/infiniband/core/cma.c:2920
Read of size 48 at addr ffff8801b0b4f9f4 by task syz-executor0/4245

CPU: 0 PID: 4245 Comm: syz-executor0 Not tainted 4.16.0-rc4+ #256
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x24d lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x23c/0x360 mm/kasan/report.c:412
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x137/0x190 mm/kasan/kasan.c:267
 memcpy+0x23/0x50 mm/kasan/kasan.c:302
 memcpy include/linux/string.h:345 [inline]
 rdma_resolve_addr+0x12e/0x26c0 drivers/infiniband/core/cma.c:2920
 ucma_resolve_ip+0x142/0x1f0 drivers/infiniband/core/ucma.c:677
 ucma_write+0x2d6/0x3d0 drivers/infiniband/core/ucma.c:1627
 __vfs_write+0xef/0x970 fs/read_write.c:480
 vfs_write+0x189/0x510 fs/read_write.c:544
 SYSC_write fs/read_write.c:589 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:581
 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline]
 do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7ffcc99
RSP: 002b:00000000ffb82d2c EFLAGS: 00000286 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000740
RDX: 0000000000000048 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea0006c2d3c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffffea0006c20101 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b0b4f900: f2 f2 f2 f2 00 00 f2 f2 00 00 00 00 00 00 00 00
 ffff8801b0b4f980: 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 00 00
>ffff8801b0b4fa00: 00 00 00 f3 f3 f3 f3 00 00 00 00 00 00 00 00 00
                            ^
 ffff8801b0b4fa80: 00 00 00 00 00 f1 f1 f1 f1 00 f2 f2 f2 f3 f3 f3
 ffff8801b0b4fb00: f3 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1
==================================================================