================================================================== BUG: KASAN: slab-out-of-bounds in ip6_dst_idev include/net/ip6_fib.h:141 [inline] BUG: KASAN: slab-out-of-bounds in ip6_xmit+0x177c/0x1a00 net/ipv6/ip6_output.c:237 Read of size 8 at addr ffff8801d107ef18 by task syz-executor0/5772 CPU: 0 PID: 5772 Comm: syz-executor0 Not tainted 4.4.152-ge5c5f1f #89 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 0000000000000000 29651aab302d4e48 ffff8801bc89f5c8 ffffffff81e15fed ffffea0007441f80 ffff8801d107ef18 0000000000000000 ffff8801d107ef18 0000000000001000 ffff8801bc89f600 ffffffff8151b489 ffff8801d107ef18 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x124 lib/dump_stack.c:51 [] print_address_description+0x6c/0x216 mm/kasan/report.c:252 [] kasan_report_error mm/kasan/report.c:351 [inline] [] kasan_report.cold.7+0x175/0x2f7 mm/kasan/report.c:408 [] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:429 [] ip6_dst_idev include/net/ip6_fib.h:141 [inline] [] ip6_xmit+0x177c/0x1a00 net/ipv6/ip6_output.c:237 [] inet6_csk_xmit+0x245/0x490 net/ipv6/inet6_connection_sock.c:176 [] l2tp_xmit_core net/l2tp/l2tp_core.c:1084 [inline] [] l2tp_xmit_skb+0xb9c/0xe80 net/l2tp/l2tp_core.c:1179 [] pppol2tp_sendmsg+0x4e0/0x7d0 net/l2tp/l2tp_ppp.c:355 [] sock_sendmsg_nosec net/socket.c:638 [inline] [] sock_sendmsg+0xcc/0x110 net/socket.c:648 [] ___sys_sendmsg+0x441/0x880 net/socket.c:1975 [] __sys_sendmmsg+0x12e/0x2e0 net/socket.c:2060 [] SYSC_sendmmsg net/socket.c:2090 [inline] [] SyS_sendmmsg+0x35/0x60 net/socket.c:2085 [] entry_SYSCALL_64_fastpath+0x22/0x9e Allocated by task 5772: [] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63 [] save_stack+0x43/0xd0 mm/kasan/kasan.c:512 [] set_track mm/kasan/kasan.c:524 [inline] [] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:616 [] kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:554 [] slab_post_alloc_hook mm/slub.c:1349 [inline] [] slab_alloc_node mm/slub.c:2615 [inline] [] slab_alloc mm/slub.c:2623 [inline] [] kmem_cache_alloc+0xbe/0x2a0 mm/slub.c:2628 [] dst_alloc+0xb5/0x1a0 net/core/dst.c:210 [] rt_dst_alloc+0x78/0x430 net/ipv4/route.c:1478 [] __mkroute_output net/ipv4/route.c:2132 [inline] [] __ip_route_output_key_hash+0x9ac/0x2380 net/ipv4/route.c:2344 [] __ip_route_output_key include/net/route.h:124 [inline] [] ip_route_output_flow+0x29/0xa0 net/ipv4/route.c:2431 [] ip_route_connect include/net/route.h:304 [inline] [] __ip4_datagram_connect+0x663/0xfe0 net/ipv4/datagram.c:51 [] __ip6_datagram_connect+0x1280/0x1960 net/ipv6/datagram.c:105 [] ip6_datagram_connect+0x2f/0x50 net/ipv6/datagram.c:223 [] inet_dgram_connect+0x117/0x200 net/ipv4/af_inet.c:550 [] SYSC_connect+0x1b8/0x300 net/socket.c:1570 [] SyS_connect+0x24/0x30 net/socket.c:1551 [] entry_SYSCALL_64_fastpath+0x22/0x9e Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8801d107edc0 which belongs to the cache ip_dst_cache of size 208 The buggy address is located 136 bytes to the right of 208-byte region [ffff8801d107edc0, ffff8801d107ee90) The buggy address belongs to the page: PANIC: double fault, error_code: 0x0 CPU: 0 PID: 5772 Comm: syz-executor0 Not tainted 4.4.152-ge5c5f1f #89 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8801d0be4800 task.stack: ffff8801bc898000 RIP: 0010:[] [] dump_page_badflags+0x1a/0x70 mm/debug.c:84 RSP: 0018:ffff8800fffffff8 EFLAGS: 00010092 RAX: 0000000000040000 RBX: ffffea0007441f80 RCX: ffffc90000c60000 RDX: 0000000000000000 RSI: ffffffff83aaae60 RDI: ffffea0007441f80 RBP: ffff880100000028 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffffffff858f0274 R12: 0000000000000000 R13: ffffffff83aaae60 R14: ffff8801d107edc0 R15: ffff8801d107ee90 FS: 00007efecfb48700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff8800ffffffe8 CR3: 00000001cea9c000 CR4: 00000000001606f0 Stack: BUG: unable to handle kernel paging request at ffff8800fffffff8 IP: [] show_stack_log_lvl.cold.1+0x73/0x12e arch/x86/kernel/dumpstack_64.c:287 PGD 6330067 PUD 0 Thread overran stack, or stack corrupted Oops: 0000 [#1] PREEMPT SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 0 PID: 5772 Comm: syz-executor0 Not tainted 4.4.152-ge5c5f1f #89 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8801d0be4800 task.stack: ffff8801bc898000 RIP: 0010:[] [] show_stack_log_lvl.cold.1+0x73/0x12e arch/x86/kernel/dumpstack_64.c:287 RSP: 0018:ffff8801db20ce68 EFLAGS: 00010046 RAX: ffff880100000000 RBX: 0000000000000000 RCX: ffff8801db207fc0 RDX: ffff8800fffffff8 RSI: ffffffff81e75b5b RDI: ffffffff83c15480 RBP: ffff8801db20cec0 R08: ffff8801db1fffc0 R09: 0000000000000000 R10: 0000000000000001 R11: ffffffff858f0254 R12: ffffffff841dc94c R13: ffff8801db20cf58 R14: 0000000000000000 R15: ffffffff841dc93a FS: 00007efecfb48700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff8800fffffff8 CR3: 00000001cea9c000 CR4: 00000000001606f0 Stack: ffffffff841dc94c ffff8801d0be4800 29651aab302d4e48 0000000000000001 ffff880100000000 ffff8800fffffff8 ffff8801db20cf58 ffff8800fffffff8 0000000000000040 ffff8800fffffff8 ffff8801d107ee90 ffff8801db20cf00 Call Trace: <#DF> [] show_regs.cold.2+0xa0/0x124 arch/x86/kernel/dumpstack_64.c:320 [] df_debug+0x1c/0x2d arch/x86/kernel/doublefault.c:80 [] do_double_fault+0x113/0x230 arch/x86/kernel/traps.c:351 [] double_fault+0x2d/0x40 arch/x86/entry/entry_64.S:886 <> Code: ec 8f 2f 00 48 8b 55 c8 48 8b 4d c0 4c 8b 45 b8 44 8b 4d b4 48 8d 42 08 41 f6 c1 03 48 89 45 c8 75 6a 45 85 c9 0f 85 8a 00 00 00 <48> 8b 12 4c 89 e6 48 c7 c7 42 c9 1d 84 44 89 4d b4 4c 89 45 b8 RIP [] show_stack_log_lvl.cold.1+0x73/0x12e arch/x86/kernel/dumpstack_64.c:287 RSP CR2: ffff8800fffffff8 ---[ end trace 233fd3c18c110a7d ]---