================================================================== BUG: KASAN: use-after-free in tipc_mcast_xmit+0xb77/0xdb0 net/tipc/bcast.c:305 Read of size 1 at addr ffff8881cbac924e by task syz-executor3/20670 CPU: 0 PID: 20670 Comm: syz-executor3 Not tainted 4.20.0-rc6+ #235 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+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430 tipc_mcast_xmit+0xb77/0xdb0 net/tipc/bcast.c:305 tipc_send_group_bcast+0xa5f/0xdf0 net/tipc/socket.c:1054 __tipc_sendmsg+0xeec/0x1d40 net/tipc/socket.c:1310 tipc_sendmsg+0x50/0x70 net/tipc/socket.c:1275 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2116 ieee80211 phy23: Selected rate control algorithm 'minstrel_ht' __sys_sendmsg+0x11d/0x280 net/socket.c:2154 kobject: 'net' (00000000b62e151b): kobject_add_internal: parent: 'hwsim23', set: '(null)' kobject: 'wlan1' (000000002d5064fe): kobject_add_internal: parent: 'net', set: 'devices' __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 kobject: 'wlan1' (000000002d5064fe): kobject_uevent_env do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 kobject: 'wlan1' (000000002d5064fe): fill_kobj_path: path = '/devices/virtual/mac80211_hwsim/hwsim23/net/wlan1' kobject: 'queues' (0000000011aca71a): kobject_add_internal: parent: 'wlan1', set: '' entry_SYSCALL_64_after_hwframe+0x49/0xbe kobject: 'queues' (0000000011aca71a): kobject_uevent_env RIP: 0033:0x457669 Code: fd b3 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 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f73e1059c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e kobject: 'queues' (0000000011aca71a): kobject_uevent_env: filter function caused the event to drop! RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457669 RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000004 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f73e105a6d4 R13: 00000000004c44bd R14: 00000000004d74a8 R15: 00000000ffffffff Allocated by task 20670: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kobject: 'rx-0' (00000000d10e93f0): kobject_add_internal: parent: 'queues', set: 'queues' kmem_cache_alloc_trace+0x152/0x750 mm/slab.c:3620 kmalloc include/linux/slab.h:546 [inline] kzalloc include/linux/slab.h:741 [inline] tipc_group_create+0x152/0xa70 net/tipc/group.c:171 tipc_sk_join net/tipc/socket.c:2836 [inline] tipc_setsockopt+0x2d1/0xd70 net/tipc/socket.c:2951 kobject: 'rx-0' (00000000d10e93f0): kobject_uevent_env __sys_setsockopt+0x1ba/0x3c0 net/socket.c:1902 __do_sys_setsockopt net/socket.c:1913 [inline] __se_sys_setsockopt net/socket.c:1910 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1910 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 20679: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 kobject: 'rx-0' (00000000d10e93f0): fill_kobj_path: path = '/devices/virtual/mac80211_hwsim/hwsim23/net/wlan1/queues/rx-0' __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 tipc_group_delete+0x2e4/0x3f0 net/tipc/group.c:227 kobject: 'tx-0' (0000000004bd1c70): kobject_add_internal: parent: 'queues', set: 'queues' tipc_sk_leave+0x113/0x220 net/tipc/socket.c:2870 tipc_setsockopt+0x97d/0xd70 net/tipc/socket.c:2954 __sys_setsockopt+0x1ba/0x3c0 net/socket.c:1902 __do_sys_setsockopt net/socket.c:1913 [inline] __se_sys_setsockopt net/socket.c:1910 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1910 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8881cbac9200 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 78 bytes inside of 192-byte region [ffff8881cbac9200, ffff8881cbac92c0) The buggy address belongs to the page: kobject: 'tx-0' (0000000004bd1c70): kobject_uevent_env page:ffffea00072eb240 count:1 mapcount:0 mapping:ffff8881da800040 index:0x0 flags: 0x2fffc0000000200(slab) raw: 02fffc0000000200 ffffea00063f4b88 ffffea000746e048 ffff8881da800040 kobject: 'tx-0' (0000000004bd1c70): fill_kobj_path: path = '/devices/virtual/mac80211_hwsim/hwsim23/net/wlan1/queues/tx-0' raw: 0000000000000000 ffff8881cbac9000 0000000100000010 0000000000000000 kobject: 'tx-1' (00000000c1b8333c): kobject_add_internal: parent: 'queues', set: 'queues' page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881cbac9100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881cbac9180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc kobject: 'tx-1' (00000000c1b8333c): kobject_uevent_env >ffff8881cbac9200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881cbac9280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8881cbac9300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb kobject: 'tx-1' (00000000c1b8333c): fill_kobj_path: path = '/devices/virtual/mac80211_hwsim/hwsim23/net/wlan1/queues/tx-1' ==================================================================