================================================================== BUG: KASAN: slab-out-of-bounds in batadv_interface_tx+0xa24/0x1470 net/batman-adv/soft-interface.c:226 Read of size 2 at addr ffff88809eefa34b by task syz-executor4/11802 CPU: 1 PID: 11802 Comm: syz-executor4 Not tainted 5.0.0-rc4-next-20190201 #25 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/generic_report.c:142 batadv_interface_tx+0xa24/0x1470 net/batman-adv/soft-interface.c:226 __netdev_start_xmit include/linux/netdevice.h:4388 [inline] netdev_start_xmit include/linux/netdevice.h:4397 [inline] dev_direct_xmit+0x346/0x640 net/core/dev.c:3930 packet_direct_xmit+0xfb/0x170 net/packet/af_packet.c:246 packet_snd net/packet/af_packet.c:2933 [inline] packet_sendmsg+0x3879/0x5ab0 net/packet/af_packet.c:2958 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:631 __sys_sendto+0x262/0x380 net/socket.c:1786 __do_sys_sendto net/socket.c:1798 [inline] __se_sys_sendto net/socket.c:1794 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1794 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457e39 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ff3a80a2c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457e39 RDX: 000000000000000e RSI: 0000000020000080 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff3a80a36d4 R13: 00000000004c548a R14: 00000000004d9260 R15: 00000000ffffffff Allocated by task 17: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc mm/kasan/common.c:498 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:471 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:506 __do_kmalloc_node mm/slab.c:3674 [inline] __kmalloc_node+0x4e/0x70 mm/slab.c:3681 kmalloc_node include/linux/slab.h:591 [inline] alloc_arraycache mm/slab.c:567 [inline] setup_kmem_cache_node+0x12a/0x410 mm/slab.c:919 setup_kmem_cache_nodes mm/slab.c:3822 [inline] __do_tune_cpucache+0x161/0x220 mm/slab.c:3892 do_tune_cpucache+0x25/0xd0 mm/slab.c:3901 enable_cpucache+0x3e/0xd0 mm/slab.c:3982 setup_cpu_cache+0xd4/0x1e0 mm/slab.c:1824 __kmem_cache_create+0x1bb/0x270 mm/slab.c:2137 create_cache+0xd4/0x200 mm/slab_common.c:391 memcg_create_kmem_cache+0x123/0x180 mm/slab_common.c:664 memcg_kmem_cache_create_func+0x56/0xe0 mm/memcontrol.c:2501 process_one_work+0x98e/0x1790 kernel/workqueue.c:2257 worker_thread+0x98/0xe40 kernel/workqueue.c:2403 kthread+0x357/0x430 kernel/kthread.c:247 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff88809eefa440 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 245 bytes to the left of 4096-byte region [ffff88809eefa440, ffff88809eefb440) The buggy address belongs to the page: page:ffffea00027bbe80 count:1 mapcount:0 mapping:ffff88812c3f0dc0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea000219c408 ffffea00027cdb88 ffff88812c3f0dc0 raw: 0000000000000000 ffff88809eefa440 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809eefa200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809eefa280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88809eefa300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88809eefa380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809eefa400: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ==================================================================