audit: type=1400 audit(1592283607.632:8): avc:  denied  { execmem } for  pid=6332 comm="syz-executor575" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1
==================================================================
BUG: KASAN: slab-out-of-bounds in __ext4_check_dir_entry+0x2f9/0x340 fs/ext4/dir.c:68
Read of size 2 at addr ffff8880a545e002 by task syz-executor575/6332

CPU: 0 PID: 6332 Comm: syz-executor575 Not tainted 4.14.184-syzkaller #0
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+0x1b2/0x283 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1dc mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0xa9/0x2b9 mm/kasan/report.c:393
 __ext4_check_dir_entry+0x2f9/0x340 fs/ext4/dir.c:68
 ext4_readdir+0x819/0x27e0 fs/ext4/dir.c:240
 iterate_dir+0x1a0/0x5e0 fs/readdir.c:52
 SYSC_getdents fs/readdir.c:269 [inline]
 SyS_getdents+0x132/0x260 fs/readdir.c:250
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x440329
RSP: 002b:00007fff22cd97a8 EFLAGS: 00000246 ORIG_RAX: 000000000000004e
RAX: ffffffffffffffda RBX: 00007fff22cd97b0 RCX: 0000000000440329
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007fff22cd97b0 R08: 65732f636f72702f R09: 65732f636f72702f
R10: 000000000000000f R11: 0000000000000246 R12: 0000000000401bb0
R13: 0000000000401c40 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 0:
(stack is not available)

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8880a545e000
 which belongs to the cache shmem_inode_cache of size 1208
The buggy address is located 2 bytes inside of
 1208-byte region [ffff8880a545e000, ffff8880a545e4b8)
The buggy address belongs to the page:
page:ffffea0002951780 count:1 mapcount:0 mapping:ffff8880a545e000 index:0xffff8880a545effd
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffff8880a545e000 ffff8880a545effd 0000000100000003
raw: ffffea0002413a60 ffff8880a9db5648 ffff8880aa9da3c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a545df00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880a545df80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880a545e000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff8880a545e080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a545e100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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