kvm: pic: non byte write ================================================================== BUG: KASAN: use-after-free in deliver_ptype_list_skb net/core/dev.c:1871 [inline] BUG: KASAN: use-after-free in __netif_receive_skb_core+0x2be3/0x33d0 net/core/dev.c:4406 Read of size 2 at addr ffff88005338edc0 by task syz-fuzzer/2999 CPU: 0 PID: 2999 Comm: syz-fuzzer Not tainted 4.13.0-next-20170915+ #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x24e/0x340 mm/kasan/report.c:409 __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:428 deliver_ptype_list_skb net/core/dev.c:1871 [inline] __netif_receive_skb_core+0x2be3/0x33d0 net/core/dev.c:4406 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4461 netif_receive_skb_internal+0x10b/0x670 net/core/dev.c:4534 napi_skb_finish net/core/dev.c:4895 [inline] napi_gro_receive+0x3d0/0x500 net/core/dev.c:4926 e1000_receive_skb drivers/net/ethernet/intel/e1000/e1000_main.c:4018 [inline] e1000_clean_rx_irq+0x58d/0x1330 drivers/net/ethernet/intel/e1000/e1000_main.c:4474 e1000_clean+0xb39/0x2610 drivers/net/ethernet/intel/e1000/e1000_main.c:3819 napi_poll net/core/dev.c:5537 [inline] net_rx_action+0x792/0x1910 net/core/dev.c:5603 __do_softirq+0x2bb/0xbd0 kernel/softirq.c:284 invoke_softirq kernel/softirq.c:364 [inline] irq_exit+0x1d3/0x210 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:638 [inline] do_IRQ+0xf6/0x190 arch/x86/kernel/irq.c:253 common_interrupt+0x9d/0x9d arch/x86/entry/entry_64.S:577 RIP: 0010:__read_once_size include/linux/compiler.h:276 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x23/0x60 kernel/kcov.c:66 RSP: 0000:ffff880039577a88 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffc5 RAX: ffff88003b042080 RBX: 800000003476a025 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff812ee3c2 RDI: ffff880039577bf0 RBP: ffff880039577cb0 R08: ffff8800395773e0 R09: ffff8800395773d8 R10: ffff880039577350 R11: 1ffff100076086a3 R12: ffff88003b0d4560 R13: 0000000000000055 R14: ffff880039577c88 R15: ffff880039577be8 handle_mm_fault+0x334/0x8d0 mm/memory.c:4071 __do_page_fault+0x4f6/0xb60 arch/x86/mm/fault.c:1445 do_page_fault+0xee/0x720 arch/x86/mm/fault.c:1520 do_async_page_fault+0x72/0xc0 arch/x86/kernel/kvm.c:266 async_page_fault+0x22/0x30 arch/x86/entry/entry_64.S:1069 RIP: 0033:0x45ea48 RSP: 002b:000000c430302d18 EFLAGS: 00010246 RAX: 000000c420b2e000 RBX: 0000000000000000 RCX: 00000000000001fa RDX: 0000000000001000 RSI: 000000c420b2e030 RDI: 00007f941eaac000 RBP: 000000c430302d78 R08: 000000c4220676e8 R09: 00000000007e7680 R10: 0000000000ab1fa0 R11: 000000c4221fcf90 R12: 000000c4330b87e6 R13: 0000000000000001 R14: 000000c4330b8848 R15: 0000000000000002 Allocated by task 19759: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3627 kmalloc include/linux/slab.h:493 [inline] kzalloc include/linux/slab.h:666 [inline] fanout_add+0xa50/0x1190 net/packet/af_packet.c:1733 packet_setsockopt+0xfdc/0x1e80 net/packet/af_packet.c:3795 SYSC_setsockopt net/socket.c:1852 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1831 entry_SYSCALL_64_fastpath+0x1f/0xbe Freed by task 19759: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3503 [inline] kfree+0xca/0x250 mm/slab.c:3820 packet_release+0xa8f/0xd70 net/packet/af_packet.c:3033 sock_release+0x8d/0x1e0 net/socket.c:597 sock_close+0x16/0x20 net/socket.c:1126 __fput+0x333/0x7f0 fs/file_table.c:210 ____fput+0x15/0x20 fs/file_table.c:244 task_work_run+0x199/0x270 kernel/task_work.c:112 exit_task_work include/linux/task_work.h:21 [inline] do_exit+0xa52/0x1b40 kernel/exit.c:865 do_group_exit+0x149/0x400 kernel/exit.c:968 get_signal+0x7e8/0x17e0 kernel/signal.c:2334 do_signal+0x94/0x1ee0 arch/x86/kernel/signal.c:808 exit_to_usermode_loop+0x224/0x300 arch/x86/entry/common.c:158 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath+0x42f/0x500 arch/x86/entry/common.c:266 entry_SYSCALL_64_fastpath+0xbc/0xbe The buggy address belongs to the object at ffff88005338e540 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 2176 bytes inside of 4096-byte region [ffff88005338e540, ffff88005338f540) The buggy address belongs to the page: page:ffffea00014ce380 count:1 mapcount:0 mapping:ffff88005338e540 index:0x0 compound_mapcount: 0 flags: 0x500000000008100(slab|head) raw: 0500000000008100 ffff88005338e540 0000000000000000 0000000100000001 raw: ffffea000141c1a0 ffffea0001ab3ca0 ffff88003e800dc0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88005338ec80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88005338ed00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88005338ed80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88005338ee00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88005338ee80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================