================================================================== BUG: KASAN: slab-out-of-bounds in ip_icmp_error+0x52a/0x5a0 net/ipv4/ip_sockglue.c:404 Read of size 1 at addr ffff888092c82fff by task ksoftirqd/0/9 CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.7.0-rc7-next-20200526-syzkaller #0 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+0x18f/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 ip_icmp_error+0x52a/0x5a0 net/ipv4/ip_sockglue.c:404 tcp_v4_err+0x99e/0x1ce0 net/ipv4/tcp_ipv4.c:576 icmp_socket_deliver+0x1e1/0x360 net/ipv4/icmp.c:803 icmp_unreach+0x33b/0xab0 net/ipv4/icmp.c:920 icmp_rcv+0xee6/0x15f0 net/ipv4/icmp.c:1102 ip_protocol_deliver_rcu+0x57/0x880 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x220/0x360 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_local_deliver+0x1c8/0x4e0 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:441 [inline] ip_rcv_finish+0x1da/0x2f0 net/ipv4/ip_input.c:428 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_rcv+0xd0/0x3c0 net/ipv4/ip_input.c:539 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5268 __netif_receive_skb+0x27/0x1c0 net/core/dev.c:5382 process_backlog+0x21e/0x7a0 net/core/dev.c:6214 napi_poll net/core/dev.c:6659 [inline] net_rx_action+0x4e1/0x10d0 net/core/dev.c:6727 __do_softirq+0x268/0x9ee kernel/softirq.c:292 run_ksoftirqd kernel/softirq.c:604 [inline] run_ksoftirqd+0x89/0x100 kernel/softirq.c:596 smpboot_thread_fn+0x653/0x9e0 kernel/smpboot.c:165 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:350 Allocated by task 2848: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc mm/kasan/common.c:494 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:467 slab_post_alloc_hook mm/slab.h:586 [inline] slab_alloc_node mm/slab.c:3263 [inline] kmem_cache_alloc_node+0x13c/0x760 mm/slab.c:3575 __alloc_skb+0xba/0x5a0 net/core/skbuff.c:198 alloc_skb include/linux/skbuff.h:1083 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:492 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:549 [inline] nsim_dev_trap_report_work+0x2bb/0xbc0 drivers/net/netdevsim/dev.c:590 process_one_work+0x965/0x1690 kernel/workqueue.c:2268 worker_thread+0x96/0xe20 kernel/workqueue.c:2414 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:350 Freed by task 2848: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:455 __cache_free mm/slab.c:3426 [inline] kmem_cache_free+0x7f/0x320 mm/slab.c:3694 kfree_skbmem net/core/skbuff.c:622 [inline] kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:616 __kfree_skb net/core/skbuff.c:679 [inline] consume_skb net/core/skbuff.c:837 [inline] consume_skb+0xfb/0x3f0 net/core/skbuff.c:831 nsim_dev_trap_report drivers/net/netdevsim/dev.c:565 [inline] nsim_dev_trap_report_work+0x86d/0xbc0 drivers/net/netdevsim/dev.c:590 process_one_work+0x965/0x1690 kernel/workqueue.c:2268 worker_thread+0x96/0xe20 kernel/workqueue.c:2414 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:350 The buggy address belongs to the object at ffff888092c82e40 which belongs to the cache skbuff_head_cache of size 224 The buggy address is located 223 bytes to the right of 224-byte region [ffff888092c82e40, ffff888092c82f20) The buggy address belongs to the page: page:ffffea00024b2080 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00024a3f48 ffffea00024c4848 ffff8880a90188c0 raw: 0000000000000000 ffff888092c82080 000000010000000c 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888092c82e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888092c82f00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc >ffff888092c82f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888092c83000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888092c83080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================