================================================================== BUG: KASAN: use-after-free in ip_icmp_error+0x52a/0x5a0 net/ipv4/ip_sockglue.c:404 Read of size 1 at addr ffff88805f69e7ff by task ksoftirqd/0/9 CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.7.0-rc6-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+0x188/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:382 __kasan_report.cold+0x20/0x38 mm/kasan/report.c:511 kasan_report+0x33/0x50 mm/kasan/common.c:625 ip_icmp_error+0x52a/0x5a0 net/ipv4/ip_sockglue.c:404 tcp_v4_err+0x9b2/0x1d00 net/ipv4/tcp_ipv4.c:576 icmp_socket_deliver+0x1e4/0x360 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+0x4c2/0x1070 net/core/dev.c:6727 __do_softirq+0x26c/0x9f7 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+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 Allocated by task 9727: save_stack+0x1b/0x40 mm/kasan/common.c:49 set_track mm/kasan/common.c:57 [inline] __kasan_kmalloc mm/kasan/common.c:495 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:468 __kmalloc_reserve.isra.0+0x39/0xe0 net/core/skbuff.c:142 __alloc_skb+0xef/0x5a0 net/core/skbuff.c:210 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+0x965/0x16a0 kernel/workqueue.c:2268 worker_thread+0x96/0xe20 kernel/workqueue.c:2414 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 Freed by task 9727: save_stack+0x1b/0x40 mm/kasan/common.c:49 set_track mm/kasan/common.c:57 [inline] kasan_set_free_info mm/kasan/common.c:317 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:456 __cache_free mm/slab.c:3426 [inline] kfree+0x109/0x2b0 mm/slab.c:3757 skb_free_head+0x8b/0xa0 net/core/skbuff.c:590 skb_release_data+0x42e/0x8b0 net/core/skbuff.c:610 skb_release_all+0x46/0x60 net/core/skbuff.c:664 __kfree_skb net/core/skbuff.c:678 [inline] consume_skb net/core/skbuff.c:837 [inline] consume_skb+0xf3/0x400 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+0x965/0x16a0 kernel/workqueue.c:2268 worker_thread+0x96/0xe20 kernel/workqueue.c:2414 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 The buggy address belongs to the object at ffff88805f69e000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 2047 bytes inside of 4096-byte region [ffff88805f69e000, ffff88805f69f000) The buggy address belongs to the page: page:ffffea00017da780 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 head:ffffea00017da780 order:1 compound_mapcount:0 flags: 0xfffe0000010200(slab|head) raw: 00fffe0000010200 ffffea000162c308 ffffea0001865188 ffff8880aa002000 raw: 0000000000000000 ffff88805f69e000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88805f69e680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805f69e700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805f69e780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805f69e800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805f69e880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================