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+0x1610/0x18c0 net/batman-adv/soft-interface.c:226 Read of size 2 at addr ffff888091c0f0cb by task syz-executor033/7713 CPU: 0 PID: 7713 Comm: syz-executor033 Not tainted 4.20.0+ #391 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.8+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:443 batadv_interface_tx+0x1610/0x18c0 net/batman-adv/soft-interface.c:226 __netdev_start_xmit include/linux/netdevice.h:4356 [inline] netdev_start_xmit include/linux/netdevice.h:4365 [inline] dev_direct_xmit+0x378/0x6b0 net/core/dev.c:3909 packet_direct_xmit+0xfb/0x170 net/packet/af_packet.c:246 packet_snd net/packet/af_packet.c:2932 [inline] packet_sendmsg+0x43a7/0x69a0 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: 0033:0x4416e9 Code: 26 02 00 85 c0 b8 00 00 00 00 48 0f 44 c3 5b c3 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 db 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffe394b79a8 EFLAGS: 00000216 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004416e9 RDX: 000000000000000e RSI: 0000000020000180 RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000216 R12: 0000000000402650 R13: 00000000004026e0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 7397: 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 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc+0x12e/0x730 mm/slab.c:3554 getname_flags+0xd0/0x590 fs/namei.c:140 user_path_at_empty+0x2d/0x50 fs/namei.c:2608 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0x129/0x210 fs/stat.c:185 vfs_stat include/linux/fs.h:3165 [inline] __do_sys_newstat+0x8f/0x110 fs/stat.c:339 __se_sys_newstat fs/stat.c:335 [inline] __x64_sys_newstat+0x54/0x80 fs/stat.c:335 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7397: 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 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x83/0x290 mm/slab.c:3760 putname+0xf2/0x130 fs/namei.c:261 filename_lookup+0x39a/0x520 fs/namei.c:2357 user_path_at_empty+0x40/0x50 fs/namei.c:2608 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0x129/0x210 fs/stat.c:185 vfs_stat include/linux/fs.h:3165 [inline] __do_sys_newstat+0x8f/0x110 fs/stat.c:339 __se_sys_newstat fs/stat.c:335 [inline] __x64_sys_newstat+0x54/0x80 fs/stat.c:335 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 ffff888091c0e900 which belongs to the cache names_cache of size 4096 The buggy address is located 1995 bytes inside of 4096-byte region [ffff888091c0e900, ffff888091c0f900) The buggy address belongs to the page: page:ffffea0002470380 count:1 mapcount:0 mapping:ffff88812c2ccc40 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0002393088 ffffea0002462a08 ffff88812c2ccc40 raw: 0000000000000000 ffff888091c0e900 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888091c0ef80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888091c0f000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888091c0f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888091c0f100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888091c0f180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================