================================================================== BUG: KASAN: use-after-free in batadv_interface_tx+0x1194/0x1880 net/batman-adv/soft-interface.c:226 Read of size 2 at addr ffff8880a3dfeccb by task syz-executor5/8018 CPU: 1 PID: 8018 Comm: syz-executor5 Not tainted 5.0.0-rc2+ #28 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+0x1db/0x2d0 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:145 batadv_interface_tx+0x1194/0x1880 net/batman-adv/soft-interface.c:226 __netdev_start_xmit include/linux/netdevice.h:4382 [inline] netdev_start_xmit include/linux/netdevice.h:4391 [inline] dev_direct_xmit+0x368/0x670 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+0x27fb/0x6920 net/packet/af_packet.c:2958 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:631 __sys_sendto+0x387/0x5f0 net/socket.c:1788 __do_sys_sendto net/socket.c:1800 [inline] __se_sys_sendto net/socket.c:1796 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1796 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 kobject: 'batman_adv' (000000009683d8a9): kobject_add_internal: parent: 'gretap0', set: '' entry_SYSCALL_64_after_hwframe+0x49/0xbe kobject: 'erspan0' (00000000ed582767): kobject_add_internal: parent: 'net', set: 'devices' RIP: 0033:0x458099 Code: 6d b7 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 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fef37fe8c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000458099 RDX: 000000000000000e RSI: 0000000020000180 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fef37fe96d4 R13: 00000000004c568c R14: 00000000004d9358 R15: 00000000ffffffff kobject: 'erspan0' (00000000ed582767): kobject_uevent_env Allocated by task 6989: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] __kasan_kmalloc mm/kasan/common.c:496 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469 kasan_kmalloc mm/kasan/common.c:504 [inline] kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:411 kobject: 'erspan0' (00000000ed582767): fill_kobj_path: path = '/devices/virtual/net/erspan0' kmem_cache_alloc+0x12d/0x710 mm/slab.c:3543 getname_flags fs/namei.c:140 [inline] getname_flags+0xd6/0x5b0 fs/namei.c:129 getname+0x1a/0x20 fs/namei.c:211 do_sys_open+0x3a5/0x7c0 fs/open.c:1057 __do_sys_open fs/open.c:1081 [inline] __se_sys_open fs/open.c:1076 [inline] __x64_sys_open+0x7e/0xc0 fs/open.c:1076 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 6989: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:458 kasan_slab_free+0xe/0x10 mm/kasan/common.c:466 kobject: 'queues' (00000000eb2ef428): kobject_add_internal: parent: 'erspan0', set: '' __cache_free mm/slab.c:3487 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3749 kobject: 'queues' (00000000eb2ef428): kobject_uevent_env putname+0xef/0x130 fs/namei.c:261 do_sys_open+0x3f4/0x7c0 fs/open.c:1072 __do_sys_open fs/open.c:1081 [inline] __se_sys_open fs/open.c:1076 [inline] __x64_sys_open+0x7e/0xc0 fs/open.c:1076 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880a3dfe500 which belongs to the cache names_cache of size 4096 The buggy address is located 1995 bytes inside of 4096-byte region [ffff8880a3dfe500, ffff8880a3dff500) The buggy address belongs to the page: kobject: 'queues' (00000000eb2ef428): kobject_uevent_env: filter function caused the event to drop! page:ffffea00028f7f80 count:1 mapcount:0 mapping:ffff8880aa16adc0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0001905688 ffffea0001810008 ffff8880aa16adc0 raw: 0000000000000000 ffff8880a3dfe500 0000000100000001 0000000000000000 kobject: 'rx-0' (0000000073af0289): kobject_add_internal: parent: 'queues', set: 'queues' page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a3dfeb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a3dfec00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880a3dfec80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ kobject: 'rx-0' (0000000073af0289): kobject_uevent_env ffff8880a3dfed00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a3dfed80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================