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BUG: KASAN: slab-out-of-bounds in __read_once_size include/linux/compiler.h:188 [inline]
BUG: KASAN: slab-out-of-bounds in bpf_fd_array_map_lookup_elem+0x440/0x4c0 kernel/bpf/arraymap.c:374
Read of size 8 at addr ffff8801c57f7b90 by task syz-executor5/11809

CPU: 0 PID: 11809 Comm: syz-executor5 Not tainted 4.15.0-rc7-mm1+ #53
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:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x23b/0x360 mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 __read_once_size include/linux/compiler.h:188 [inline]
 bpf_fd_array_map_lookup_elem+0x440/0x4c0 kernel/bpf/arraymap.c:374
 map_lookup_elem+0x6b5/0xbd0 kernel/bpf/syscall.c:577
 SYSC_bpf kernel/bpf/syscall.c:1808 [inline]
 SyS_bpf+0x922/0x4400 kernel/bpf/syscall.c:1782
 entry_SYSCALL_64_fastpath+0x29/0xa0
RIP: 0033:0x452ac9
RSP: 002b:00007f404237ec58 EFLAGS: 00000212 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452ac9
RDX: 0000000000000018 RSI: 0000000020f00fe8 RDI: 0000000000000001
RBP: 00000000000003aa R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f3890
R13: 00000000ffffffff R14: 00007f404237f6d4 R15: 0000000000000000

Allocated by task 3540:
 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:552
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489
 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3541
 getname_flags+0xcb/0x580 fs/namei.c:138
 getname+0x19/0x20 fs/namei.c:209
 do_sys_open+0x2e7/0x6d0 fs/open.c:1053
 SYSC_open fs/open.c:1077 [inline]
 SyS_open+0x2d/0x40 fs/open.c:1072
 entry_SYSCALL_64_fastpath+0x29/0xa0

Freed by task 3540:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:520
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:527
 __cache_free mm/slab.c:3485 [inline]
 kmem_cache_free+0x86/0x2b0 mm/slab.c:3743
 putname+0xee/0x130 fs/namei.c:258
 do_sys_open+0x31b/0x6d0 fs/open.c:1068
 SYSC_open fs/open.c:1077 [inline]
 SyS_open+0x2d/0x40 fs/open.c:1072
 entry_SYSCALL_64_fastpath+0x29/0xa0

The buggy address belongs to the object at ffff8801c57f64c0
 which belongs to the cache names_cache of size 4096
The buggy address is located 1744 bytes to the right of
 4096-byte region [ffff8801c57f64c0, ffff8801c57f74c0)
The buggy address belongs to the page:
page:ffffea000715fd80 count:1 mapcount:0 mapping:ffff8801c57f64c0 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff8801c57f64c0 0000000000000000 0000000100000001
raw: ffffea000742e920 ffffea000715e120 ffff8801dae30600 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c57f7a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801c57f7b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8801c57f7b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                         ^
 ffff8801c57f7c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801c57f7c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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