================================================================== BUG: KASAN: slab-out-of-bounds in atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] BUG: KASAN: slab-out-of-bounds in atomic_fetch_add_unless include/linux/atomic-fallback.h:1086 [inline] BUG: KASAN: slab-out-of-bounds in atomic_add_unless include/linux/atomic-fallback.h:1111 [inline] BUG: KASAN: slab-out-of-bounds in atomic_inc_not_zero include/linux/atomic-fallback.h:1127 [inline] BUG: KASAN: slab-out-of-bounds in dst_hold_safe include/net/dst.h:308 [inline] BUG: KASAN: slab-out-of-bounds in ip6_hold_safe+0xb3/0x3a0 net/ipv6/route.c:1023 Read of size 4 at addr ffff8880913b2529 by task syz-executor.1/27330 CPU: 1 PID: 27330 Comm: syz-executor.1 Not tainted 5.1.0-rc6+ #185 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+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 kasan_check_read+0x11/0x20 mm/kasan/common.c:102 atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] atomic_fetch_add_unless include/linux/atomic-fallback.h:1086 [inline] atomic_add_unless include/linux/atomic-fallback.h:1111 [inline] atomic_inc_not_zero include/linux/atomic-fallback.h:1127 [inline] dst_hold_safe include/net/dst.h:308 [inline] ip6_hold_safe+0xb3/0x3a0 net/ipv6/route.c:1023 rt6_get_pcpu_route net/ipv6/route.c:1245 [inline] ip6_pol_route+0x348/0x1040 net/ipv6/route.c:1906 ip6_pol_route_input+0x65/0x80 net/ipv6/route.c:1925 fib6_rule_lookup+0x128/0x560 net/ipv6/fib6_rules.c:118 ip6_route_input_lookup+0xb7/0xd0 net/ipv6/route.c:1937 ip6_route_input+0x5e2/0x9e0 net/ipv6/route.c:2072 ip6_rcv_finish_core.isra.0+0x174/0x590 net/ipv6/ip6_input.c:63 ip6_rcv_finish+0x17d/0x320 net/ipv6/ip6_input.c:74 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ipv6_rcv+0x10e/0x420 net/ipv6/ip6_input.c:272 __netif_receive_skb_one_core+0x115/0x1a0 net/core/dev.c:4987 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5099 netif_receive_skb_internal+0x117/0x660 net/core/dev.c:5202 napi_frags_finish net/core/dev.c:5769 [inline] napi_gro_frags+0xade/0xd10 net/core/dev.c:5843 tun_get_user+0x2f24/0x3fb0 drivers/net/tun.c:1981 tun_chr_write_iter+0xbd/0x156 drivers/net/tun.c:2027 call_write_iter include/linux/fs.h:1866 [inline] do_iter_readv_writev+0x5e1/0x8e0 fs/read_write.c:681 do_iter_write fs/read_write.c:957 [inline] do_iter_write+0x184/0x610 fs/read_write.c:938 vfs_writev+0x1b3/0x2f0 fs/read_write.c:1002 do_writev+0x15e/0x370 fs/read_write.c:1037 __do_sys_writev fs/read_write.c:1110 [inline] __se_sys_writev fs/read_write.c:1107 [inline] __x64_sys_writev+0x75/0xb0 fs/read_write.c:1107 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c61 Code: 75 14 b8 14 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 e4 b9 fb ff c3 48 83 ec 08 e8 1a 2d 00 00 48 89 04 24 b8 14 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 63 2d 00 00 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007f8d3e021ba0 EFLAGS: 00000293 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 0000000000000074 RCX: 0000000000458c61 RDX: 0000000000000001 RSI: 00007f8d3e021c00 RDI: 00000000000000f0 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f8d3e0226d4 R13: 00000000004c76b6 R14: 00000000004dd610 R15: 00000000ffffffff Allocated by task 13753: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc mm/kasan/common.c:497 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:505 slab_post_alloc_hook mm/slab.h:437 [inline] slab_alloc mm/slab.c:3393 [inline] kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3555 dst_alloc+0x10e/0x200 net/core/dst.c:109 ip6_dst_alloc+0x34/0xa0 net/ipv6/route.c:355 ip6_rt_pcpu_alloc net/ipv6/route.c:1225 [inline] rt6_make_pcpu_route net/ipv6/route.c:1255 [inline] ip6_pol_route+0x743/0x1040 net/ipv6/route.c:1909 ip6_pol_route_input+0x65/0x80 net/ipv6/route.c:1925 fib6_rule_lookup+0x128/0x560 net/ipv6/fib6_rules.c:118 ip6_route_input_lookup+0xb7/0xd0 net/ipv6/route.c:1937 ip6_route_input+0x5e2/0x9e0 net/ipv6/route.c:2072 ip6_rcv_finish_core.isra.0+0x174/0x590 net/ipv6/ip6_input.c:63 ip6_rcv_finish+0x17d/0x320 net/ipv6/ip6_input.c:74 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ipv6_rcv+0x10e/0x420 net/ipv6/ip6_input.c:272 __netif_receive_skb_one_core+0x115/0x1a0 net/core/dev.c:4987 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5099 netif_receive_skb_internal+0x117/0x660 net/core/dev.c:5202 napi_frags_finish net/core/dev.c:5769 [inline] napi_gro_frags+0xade/0xd10 net/core/dev.c:5843 tun_get_user+0x2f24/0x3fb0 drivers/net/tun.c:1981 tun_chr_write_iter+0xbd/0x156 drivers/net/tun.c:2027 call_write_iter include/linux/fs.h:1866 [inline] do_iter_readv_writev+0x5e1/0x8e0 fs/read_write.c:681 do_iter_write fs/read_write.c:957 [inline] do_iter_write+0x184/0x610 fs/read_write.c:938 vfs_writev+0x1b3/0x2f0 fs/read_write.c:1002 do_writev+0x15e/0x370 fs/read_write.c:1037 __do_sys_writev fs/read_write.c:1110 [inline] __se_sys_writev fs/read_write.c:1107 [inline] __x64_sys_writev+0x75/0xb0 fs/read_write.c:1107 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7946: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467 __cache_free mm/slab.c:3499 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3765 dst_destroy+0x2a0/0x3c0 net/core/dst.c:145 dst_destroy_rcu+0x16/0x19 net/core/dst.c:158 __rcu_reclaim kernel/rcu/rcu.h:227 [inline] rcu_do_batch kernel/rcu/tree.c:2475 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2788 [inline] rcu_core+0x916/0x13a0 kernel/rcu/tree.c:2769 __do_softirq+0x266/0x95a kernel/softirq.c:293 The buggy address belongs to the object at ffff8880913b2440 which belongs to the cache ip6_dst_cache of size 224 The buggy address is located 9 bytes to the right of 224-byte region [ffff8880913b2440, ffff8880913b2520) The buggy address belongs to the page: page:ffffea000244ec80 count:1 mapcount:0 mapping:ffff888216417b00 index:0xffff8880913b2a80 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00026f5288 ffffea0002336588 ffff888216417b00 raw: ffff8880913b2a80 ffff8880913b2080 0000000100000007 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880913b2400: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff8880913b2480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880913b2500: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880913b2580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880913b2600: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ==================================================================