bridge: RTM_NEWNEIGH with invalid state 0x0 ================================================================== BUG: KASAN: use-after-free in erspan_build_header+0x3bf/0x3d0 net/ipv4/ip_gre.c:698 Read of size 2 at addr ffff8801a6bdd2cb by task syz-executor0/11793 CPU: 0 PID: 11793 Comm: syz-executor0 Not tainted 4.15.0-rc9+ #282 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:440 erspan_build_header+0x3bf/0x3d0 net/ipv4/ip_gre.c:698 erspan_xmit+0x3b8/0x13b0 net/ipv4/ip_gre.c:740 __netdev_start_xmit include/linux/netdevice.h:4042 [inline] netdev_start_xmit include/linux/netdevice.h:4051 [inline] packet_direct_xmit+0x315/0x6b0 net/packet/af_packet.c:266 packet_snd net/packet/af_packet.c:2943 [inline] packet_sendmsg+0x3aed/0x60b0 net/packet/af_packet.c:2968 sock_sendmsg_nosec net/socket.c:638 [inline] sock_sendmsg+0xca/0x110 net/socket.c:648 SYSC_sendto+0x361/0x5c0 net/socket.c:1729 SyS_sendto+0x40/0x50 net/socket.c:1697 entry_SYSCALL_64_fastpath+0x29/0xa0 RIP: 0033:0x452f19 RSP: 002b:00007f5391063c58 EFLAGS: 00000212 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f5391064700 RCX: 0000000000452f19 RDX: 0000000000000000 RSI: 0000000020003fd9 RDI: 0000000000000013 RBP: 0000000000000000 R08: 0000000020008000 R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 R13: 0000000000a2f7cf R14: 00007f53910649c0 R15: 0000000000000000 Allocated by task 3706: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3544 getname_flags+0xcb/0x580 fs/namei.c:138 user_path_at_empty+0x2d/0x50 fs/namei.c:2590 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xe9/0x190 fs/stat.c:185 vfs_lstat include/linux/fs.h:3085 [inline] SYSC_newlstat+0x87/0xf0 fs/stat.c:350 SyS_newlstat+0x1d/0x30 fs/stat.c:344 entry_SYSCALL_64_fastpath+0x29/0xa0 Freed by task 3706: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3488 [inline] kmem_cache_free+0x83/0x2a0 mm/slab.c:3746 putname+0xee/0x130 fs/namei.c:258 filename_lookup+0x315/0x500 fs/namei.c:2345 user_path_at_empty+0x40/0x50 fs/namei.c:2590 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xe9/0x190 fs/stat.c:185 vfs_lstat include/linux/fs.h:3085 [inline] SYSC_newlstat+0x87/0xf0 fs/stat.c:350 SyS_newlstat+0x1d/0x30 fs/stat.c:344 entry_SYSCALL_64_fastpath+0x29/0xa0 The buggy address belongs to the object at ffff8801a6bdc500 which belongs to the cache names_cache of size 4096 The buggy address is located 3531 bytes inside of 4096-byte region [ffff8801a6bdc500, ffff8801a6bdd500) The buggy address belongs to the page: page:ffffea00069af700 count:1 mapcount:0 mapping:ffff8801a6bdc500 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffff8801a6bdc500 0000000000000000 0000000100000001 raw: ffffea00069af4a0 ffffea00069af7a0 ffff8801dae2c600 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801a6bdd180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801a6bdd200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801a6bdd280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801a6bdd300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801a6bdd380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================