================================================================== BUG: KASAN: slab-out-of-bounds in ip6_tnl_parse_tlv_enc_lim+0x5df/0x660 net/ipv6/ip6_tunnel.c:417 Read of size 1 at addr ffff8801d195f7c7 by task syz-executor1/26890 CPU: 0 PID: 26890 Comm: syz-executor1 Not tainted 4.19.0-rc7+ #58 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+0x1c4/0x2b4 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_load1_noabort+0x14/0x20 mm/kasan/report.c:430 ip6_tnl_parse_tlv_enc_lim+0x5df/0x660 net/ipv6/ip6_tunnel.c:417 ip6ip6_tnl_xmit net/ipv6/ip6_tunnel.c:1348 [inline] ip6_tnl_start_xmit+0x49f/0x25a0 net/ipv6/ip6_tunnel.c:1412 __netdev_start_xmit include/linux/netdevice.h:4290 [inline] netdev_start_xmit include/linux/netdevice.h:4299 [inline] xmit_one net/core/dev.c:3216 [inline] dev_hard_start_xmit+0x27f/0xc70 net/core/dev.c:3232 __dev_queue_xmit+0x2f3b/0x3980 net/core/dev.c:3802 dev_queue_xmit+0x17/0x20 net/core/dev.c:3835 __bpf_tx_skb net/core/filter.c:2012 [inline] __bpf_redirect_common net/core/filter.c:2050 [inline] __bpf_redirect+0x5cf/0xb20 net/core/filter.c:2057 ____bpf_clone_redirect net/core/filter.c:2090 [inline] bpf_clone_redirect+0x2f6/0x490 net/core/filter.c:2062 bpf_prog_759a992c578a3894+0x931/0x1000 Allocated by task 26890: 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 __do_kmalloc_node mm/slab.c:3682 [inline] __kmalloc_node_track_caller+0x47/0x70 mm/slab.c:3696 __kmalloc_reserve.isra.39+0x41/0xe0 net/core/skbuff.c:137 pskb_expand_head+0x230/0x10f0 net/core/skbuff.c:1460 skb_ensure_writable+0x3dd/0x640 net/core/skbuff.c:5126 __bpf_try_make_writable net/core/filter.c:1633 [inline] bpf_try_make_writable net/core/filter.c:1639 [inline] bpf_try_make_head_writable net/core/filter.c:1647 [inline] ____bpf_clone_redirect net/core/filter.c:2084 [inline] bpf_clone_redirect+0x14a/0x490 net/core/filter.c:2062 bpf_prog_759a992c578a3894+0x931/0x1000 Freed by task 25600: 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] kfree+0xcf/0x230 mm/slab.c:3813 load_elf_binary+0x25b4/0x5620 fs/binfmt_elf.c:1118 search_binary_handler+0x17d/0x570 fs/exec.c:1653 exec_binprm fs/exec.c:1695 [inline] __do_execve_file.isra.33+0x162f/0x2540 fs/exec.c:1819 do_execveat_common fs/exec.c:1866 [inline] do_execve fs/exec.c:1883 [inline] __do_sys_execve fs/exec.c:1964 [inline] __se_sys_execve fs/exec.c:1959 [inline] __x64_sys_execve+0x8f/0xc0 fs/exec.c:1959 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 ffff8801d195f5c0 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 7 bytes to the right of 512-byte region [ffff8801d195f5c0, ffff8801d195f7c0) The buggy address belongs to the page: page:ffffea00074657c0 count:1 mapcount:0 mapping:ffff8801da800940 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea00072d10c8 ffffea0007126488 ffff8801da800940 raw: 0000000000000000 ffff8801d195f0c0 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d195f680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8801d195f700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8801d195f780: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ^ ffff8801d195f800: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff8801d195f880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================