RDX: 000000000000001c RSI: 0000000020689000 RDI: 0000000000000005 RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004b5e76 R13: 00007f1370405b48 R14: 00000000004b5e86 R15: 0000000000000000 ================================================================== BUG: KASAN: use-after-free in skb_push+0xd4/0xe0 net/core/skbuff.c:1718 Read of size 8 at addr ffff8801c7d77650 by task syz-executor2/14709 CPU: 1 PID: 14709 Comm: syz-executor2 Not tainted 4.13.0-rc4+ #5 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x24e/0x340 mm/kasan/report.c:409 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 skb_push+0xd4/0xe0 net/core/skbuff.c:1718 tipc_nl_compat_recv+0x833/0x18f0 net/tipc/netlink_compat.c:1209 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:598 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:623 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397 genl_rcv+0x28/0x40 net/netlink/genetlink.c:634 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline] netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 sock_write_iter+0x31a/0x5d0 net/socket.c:912 call_write_iter include/linux/fs.h:1743 [inline] new_sync_write fs/read_write.c:457 [inline] __vfs_write+0x684/0x970 fs/read_write.c:470 vfs_write+0x189/0x510 fs/read_write.c:518 SYSC_write fs/read_write.c:565 [inline] SyS_write+0xef/0x220 fs/read_write.c:557 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x4512e9 RSP: 002b:00007f1370405c08 EFLAGS: 00000216 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 00000000004512e9 RDX: 000000000000001c RSI: 0000000020689000 RDI: 0000000000000005 RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004b5e76 R13: 00007f1370405b48 R14: 00000000004b5e86 R15: 0000000000000000 Allocated by task 14709: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 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_node+0x13d/0x750 mm/slab.c:3651 __alloc_skb+0xf1/0x740 net/core/skbuff.c:194 alloc_skb include/linux/skbuff.h:975 [inline] tipc_tlv_alloc+0x26/0xb0 net/tipc/netlink_compat.c:148 tipc_nl_compat_dumpit+0xf2/0x3c0 net/tipc/netlink_compat.c:248 tipc_nl_compat_handle net/tipc/netlink_compat.c:1141 [inline] tipc_nl_compat_recv+0xb23/0x18f0 net/tipc/netlink_compat.c:1199 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:598 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:623 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397 genl_rcv+0x28/0x40 net/netlink/genetlink.c:634 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline] netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 sock_write_iter+0x31a/0x5d0 net/socket.c:912 call_write_iter include/linux/fs.h:1743 [inline] new_sync_write fs/read_write.c:457 [inline] __vfs_write+0x684/0x970 fs/read_write.c:470 vfs_write+0x189/0x510 fs/read_write.c:518 SYSC_write fs/read_write.c:565 [inline] SyS_write+0xef/0x220 fs/read_write.c:557 entry_SYSCALL_64_fastpath+0x1f/0xbe Freed by task 14709: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 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:3503 [inline] kmem_cache_free+0x77/0x280 mm/slab.c:3763 kfree_skbmem+0x1a1/0x1d0 net/core/skbuff.c:586 __kfree_skb net/core/skbuff.c:646 [inline] kfree_skb+0x165/0x4c0 net/core/skbuff.c:663 tipc_nl_compat_dumpit+0x36a/0x3c0 net/tipc/netlink_compat.c:260 tipc_nl_compat_handle net/tipc/netlink_compat.c:1141 [inline] tipc_nl_compat_recv+0xb23/0x18f0 net/tipc/netlink_compat.c:1199 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:598 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:623 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397 genl_rcv+0x28/0x40 net/netlink/genetlink.c:634 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline] netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 sock_write_iter+0x31a/0x5d0 net/socket.c:912 call_write_iter include/linux/fs.h:1743 [inline] new_sync_write fs/read_write.c:457 [inline] __vfs_write+0x684/0x970 fs/read_write.c:470 vfs_write+0x189/0x510 fs/read_write.c:518 SYSC_write fs/read_write.c:565 [inline] SyS_write+0xef/0x220 fs/read_write.c:557 entry_SYSCALL_64_fastpath+0x1f/0xbe The buggy address belongs to the object at ffff8801c7d77580 which belongs to the cache skbuff_head_cache of size 224 The buggy address is located 208 bytes inside of 224-byte region [ffff8801c7d77580, ffff8801c7d77660) The buggy address belongs to the page: page:ffffea00071f5dc0 count:1 mapcount:0 mapping:ffff8801c7d77080 index:0xffff8801c7d77800 flags: 0x200000000000100(slab) raw: 0200000000000100 ffff8801c7d77080 ffff8801c7d77800 0000000100000009 raw: ffffea00072307a0 ffffea00074f7e20 ffff8801d9833800 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c7d77500: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ffff8801c7d77580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801c7d77600: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff8801c7d77680: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff8801c7d77700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================