IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready 8021q: adding VLAN 0 to HW filter on device batadv0 ================================================================== BUG: KASAN: use-after-free in batadv_interface_tx+0x160a/0x18b0 net/batman-adv/soft-interface.c:226 Read of size 2 at addr ffff8880a7aca34b by task syz-executor726/8122 CPU: 1 PID: 8122 Comm: syz-executor726 Not tainted 4.20.0+ #173 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+0x1d3/0x2c6 lib/dump_stack.c:113 print_address_description.cold.5+0x9/0x1ff mm/kasan/report.c:187 kasan_report.cold.6+0x1b/0x39 mm/kasan/report.c:317 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/generic_report.c:145 batadv_interface_tx+0x160a/0x18b0 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+0x36c/0x6a0 net/core/dev.c:3930 packet_direct_xmit+0xfb/0x170 net/packet/af_packet.c:246 packet_snd net/packet/af_packet.c:2932 [inline] packet_sendmsg+0x298a/0x6ad0 net/packet/af_packet.c:2957 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 __sys_sendto+0x3d7/0x670 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+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x441619 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 0b fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fff47e932b8 EFLAGS: 00000212 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441619 RDX: 000000000000000e RSI: 0000000020000180 RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000004025e0 R13: 0000000000402670 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 7051: save_stack+0x43/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] kasan_kmalloc+0xcb/0xd0 mm/kasan/common.c:482 kmem_cache_alloc_trace+0x154/0x750 mm/slab.c:3607 kmalloc include/linux/slab.h:546 [inline] kzalloc include/linux/slab.h:741 [inline] new_task_smack+0x102/0x330 security/smack/smack_lsm.c:324 smack_cred_prepare+0xfd/0x8e0 security/smack/smack_lsm.c:2021 security_prepare_creds+0x60/0xc0 security/security.c:1022 prepare_creds+0x3b9/0x4d0 kernel/cred.c:278 do_faccessat+0xa3/0x800 fs/open.c:359 __do_sys_access fs/open.c:430 [inline] __se_sys_access fs/open.c:428 [inline] __x64_sys_access+0x59/0x80 fs/open.c:428 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7059: save_stack+0x43/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:444 kasan_slab_free+0xe/0x10 mm/kasan/common.c:452 __cache_free mm/slab.c:3485 [inline] kfree+0xcf/0x230 mm/slab.c:3804 smack_cred_free+0x256/0x370 security/smack/smack_lsm.c:2003 security_cred_free+0x4a/0x80 security/security.c:1017 put_cred_rcu+0x265/0x780 kernel/cred.c:117 __rcu_reclaim kernel/rcu/rcu.h:240 [inline] rcu_do_batch kernel/rcu/tree.c:2452 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2773 [inline] rcu_process_callbacks+0xc5b/0x1600 kernel/rcu/tree.c:2754 __do_softirq+0x30c/0xb2e kernel/softirq.c:292 The buggy address belongs to the object at ffff8880a7aca300 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 75 bytes inside of 192-byte region [ffff8880a7aca300, ffff8880a7aca3c0) The buggy address belongs to the page: page:ffffea00029eb280 count:1 mapcount:0 mapping:ffff88812c3f0040 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00029ea908 ffffea00029ea5c8 ffff88812c3f0040 raw: 0000000000000000 ffff8880a7aca000 0000000100000010 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a7aca200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a7aca280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff8880a7aca300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a7aca380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880a7aca400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================