syzbot

BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:276 [inline]
BUG: KASAN: use-after-free in atomic64_read arch/x86/include/asm/atomic64_64.h:21 [inline]
BUG: KASAN: use-after-free in atomic_long_read include/asm-generic/atomic-long.h:44 [inline]
BUG: KASAN: use-after-free in packet_getsockopt+0xc72/0xe00 net/packet/af_packet.c:3934
Read of size 8 at addr ffff8801d8f91858 by task syz-executor0/3203

CPU: 1 PID: 3203 Comm: syz-executor0 Not tainted 4.14.0-rc5+ #140
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 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_load8_noabort+0x14/0x20 mm/kasan/report.c:430
 __read_once_size include/linux/compiler.h:276 [inline]
 atomic64_read arch/x86/include/asm/atomic64_64.h:21 [inline]
 atomic_long_read include/asm-generic/atomic-long.h:44 [inline]
 packet_getsockopt+0xc72/0xe00 net/packet/af_packet.c:3934
 SYSC_getsockopt net/socket.c:1883 [inline]
 SyS_getsockopt+0x178/0x340 net/socket.c:1865
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x452719
RSP: 002b:00007f5b98c02be8 EFLAGS: 00000212 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00000000007580d8 RCX: 0000000000452719
RDX: 0000000000000015 RSI: 0000000000000107 RDI: 0000000000000010
RBP: 0000000000000082 R08: 00000000208a5000 R09: 0000000000000000
R10: 0000000020ec8000 R11: 0000000000000212 R12: 0000000000000000
R13: 00007ffcd6754f6f R14: 00007f5b98c039c0 R15: 0000000000000004

Allocated by task 3202:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 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
 kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3627
 kmalloc include/linux/slab.h:493 [inline]
 kzalloc include/linux/slab.h:666 [inline]
 fanout_add+0x27e/0x1480 net/packet/af_packet.c:1694
 packet_setsockopt+0xfdc/0x1e80 net/packet/af_packet.c:3805
 SYSC_setsockopt net/socket.c:1852 [inline]
 SyS_setsockopt+0x189/0x360 net/socket.c:1831
 entry_SYSCALL_64_fastpath+0x1f/0xbe

Freed by task 3202:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 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:3503 [inline]
 kfree+0xca/0x250 mm/slab.c:3820
 fanout_add+0x432/0x1480 net/packet/af_packet.c:1772
 packet_setsockopt+0xfdc/0x1e80 net/packet/af_packet.c:3805
 SYSC_setsockopt net/socket.c:1852 [inline]
 SyS_setsockopt+0x189/0x360 net/socket.c:1831
 entry_SYSCALL_64_fastpath+0x1f/0xbe

The buggy address belongs to the object at ffff8801d8f91840
 which belongs to the cache kmalloc-128 of size 128
The buggy address is located 24 bytes inside of
 128-byte region [ffff8801d8f91840, ffff8801d8f918c0)
The buggy address belongs to the page:
page:ffffea000763e440 count:1 mapcount:0 mapping:ffff8801d8f91000 index:0x0
flags: 0x200000000000100(slab)
raw: 0200000000000100 ffff8801d8f91000 0000000000000000 0000000100000015
raw: ffffea000763fbe0 ffffea000763e5a0 ffff8801dac00640 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d8f91700: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8801d8f91780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801d8f91800: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                                    ^
 ffff8801d8f91880: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8801d8f91900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================