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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 ffff8801af0efa44 by task syz-executor2/15080

CPU: 1 PID: 15080 Comm: syz-executor2 Not tainted 4.16.0-rc7+ #370
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+0x178/0x240 drivers/infiniband/core/ucma.c:689
 ucma_write+0x2d6/0x3d0 drivers/infiniband/core/ucma.c:1649
 __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_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4548b9
RSP: 002b:00007ff27d5c4c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007ff27d5c56d4 RCX: 00000000004548b9
RDX: 0000000000000048 RSI: 0000000020000100 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000006a9 R14: 00000000006fc078 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea0006bc3bc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffffea0006bc0101 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801af0ef900: f2 f2 f2 f2 f2 f2 00 00 f2 f2 f2 f2 f2 f2 00 00
 ffff8801af0ef980: f2 f2 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801af0efa00: 00 f1 f1 f1 f1 00 00 00 00 00 00 00 00 f3 f3 f3
                                                          ^
 ffff8801af0efa80: f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1
 ffff8801af0efb00: f1 f1 f1 00 f2 f2 f2 f3 f3 f3 f3 00 00 00 00 00
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