==================================================================
BUG: KASAN: slab-out-of-bounds in cap_convert_nscap+0x501/0x610 security/commoncap.c:498
Read of size 4 at addr ffff8801d2cc8e00 by task syz-executor0/10884

CPU: 0 PID: 10884 Comm: syz-executor0 Not tainted 4.15.0-rc4-next-20171221+ #78
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+0x194/0x257 lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x25b/0x340 mm/kasan/report.c:409
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429
 cap_convert_nscap+0x501/0x610 security/commoncap.c:498
 setxattr+0x365/0x400 fs/xattr.c:446
 SYSC_fsetxattr fs/xattr.c:508 [inline]
 SyS_fsetxattr+0x130/0x190 fs/xattr.c:497
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x452ac9
RSP: 002b:00007f7609138c58 EFLAGS: 00000212 ORIG_RAX: 00000000000000be
RAX: ffffffffffffffda RBX: 00007f7609139700 RCX: 0000000000452ac9
RDX: 00000000206aeffe RSI: 0000000020ff7fec RDI: 0000000000000013
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000212 R12: 0000000000000000
R13: 0000000000a2f7ef R14: 00007f76091399c0 R15: 0000000000000000

Allocated by task 10884:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
 __do_kmalloc_node mm/slab.c:3673 [inline]
 __kmalloc_node+0x47/0x70 mm/slab.c:3680
 kmalloc_node include/linux/slab.h:558 [inline]
 kvmalloc_node+0x99/0xd0 mm/util.c:397
 kvmalloc include/linux/mm.h:541 [inline]
 setxattr+0x152/0x400 fs/xattr.c:435
 SYSC_fsetxattr fs/xattr.c:508 [inline]
 SyS_fsetxattr+0x130/0x190 fs/xattr.c:497
 entry_SYSCALL_64_fastpath+0x1f/0x96

Freed by task 8092:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3489 [inline]
 kfree+0xd6/0x260 mm/slab.c:3804
 kvfree+0x36/0x60 mm/util.c:416
 __vunmap+0x2ac/0x380 mm/vmalloc.c:1542
 vfree+0x50/0xe0 mm/vmalloc.c:1606
 bpf_prog_calc_tag+0x466/0x6f0 kernel/bpf/core.c:217
 replace_map_fd_with_map_ptr kernel/bpf/verifier.c:4723 [inline]
 bpf_check+0x64a/0x49f0 kernel/bpf/verifier.c:5357
 bpf_prog_load+0xa2a/0x1b00 kernel/bpf/syscall.c:1192
 SYSC_bpf kernel/bpf/syscall.c:1724 [inline]
 SyS_bpf+0x1044/0x4420 kernel/bpf/syscall.c:1686
 entry_SYSCALL_64_fastpath+0x1f/0x96

The buggy address belongs to the object at ffff8801d2cc8e00
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes inside of
 32-byte region [ffff8801d2cc8e00, ffff8801d2cc8e20)
The buggy address belongs to the page:
page:000000002849d89f count:1 mapcount:0 mapping:00000000284d417b index:0xffff8801d2cc8fc1
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801d2cc8000 ffff8801d2cc8fc1 000000010000003a
raw: ffffea00074b0f60 ffffea00074ebfe0 ffff8801dac001c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d2cc8d00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
 ffff8801d2cc8d80: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
>ffff8801d2cc8e00: 02 fc fc fc fc fc fc fc 00 00 00 fc fc fc fc fc
                   ^
 ffff8801d2cc8e80: fb fb fb fb fc fc fc fc 00 01 fc fc fc fc fc fc
 ffff8801d2cc8f00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
==================================================================