================================================================== BUG: KASAN: use-after-free in skb_release_data+0x5cf/0x790 net/core/skbuff.c:567 Read of size 1 at addr ffff8800371b8e42 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.13.0-rc5-next-20170815+ #3 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_load1_noabort+0x14/0x20 mm/kasan/report.c:427 skb_release_data+0x5cf/0x790 net/core/skbuff.c:567 skb_release_all+0x4a/0x60 net/core/skbuff.c:631 __kfree_skb net/core/skbuff.c:645 [inline] kfree_skb+0x15d/0x4c0 net/core/skbuff.c:663 inet_frag_destroy+0x121/0x270 net/ipv4/inet_fragment.c:304 inet_frag_put include/net/inet_frag.h:133 [inline] ipq_put net/ipv4/ip_fragment.c:170 [inline] ip_expire+0x1be/0x6d0 net/ipv4/ip_fragment.c:254 call_timer_fn+0x233/0x830 kernel/time/timer.c:1268 expire_timers kernel/time/timer.c:1307 [inline] __run_timers+0x7fd/0xb90 kernel/time/timer.c:1601 run_timer_softirq+0x21/0x80 kernel/time/timer.c:1614 __do_softirq+0x2f5/0xba3 kernel/softirq.c:284 invoke_softirq kernel/softirq.c:364 [inline] irq_exit+0x1cc/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:638 [inline] smp_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:1044 apic_timer_interrupt+0x9d/0xb0 arch/x86/entry/entry_64.S:577 RIP: 0010:native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:53 RSP: 0018:ffffffff85a07ce0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff10 RAX: dffffc0000000000 RBX: 1ffffffff0b40f9f RCX: 0100000000000000 RDX: 1ffffffff0b58d6c RSI: 0000000000000000 RDI: ffffffff85ac6b60 RBP: ffffffff85a07ce0 R08: ffffffff857efa80 R09: 1ffffffff0b40f35 R10: ffff88007fff7010 R11: ffff88007fff701d R12: ffffffff85ac6b50 R13: ffffffff85a07d98 R14: 0000000000000000 R15: ffffffff85a2c380 arch_safe_halt arch/x86/include/asm/paravirt.h:98 [inline] default_idle+0xbf/0x460 arch/x86/kernel/process.c:341 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:332 default_idle_call+0x36/0x90 kernel/sched/idle.c:98 cpuidle_idle_call kernel/sched/idle.c:156 [inline] do_idle+0x256/0x3b0 kernel/sched/idle.c:246 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:351 rest_init+0xed/0xf0 init/main.c:435 start_kernel+0x74a/0x770 init/main.c:708 x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:378 x86_64_start_kernel+0x13c/0x149 arch/x86/kernel/head64.c:359 secondary_startup_64+0xa5/0xa5 arch/x86/kernel/head_64.S:235 Allocated by task 9692: 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 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3561 getname_flags+0xcb/0x580 fs/namei.c:137 getname+0x19/0x20 fs/namei.c:208 do_sys_open+0x2e7/0x6d0 fs/open.c:1053 SYSC_open fs/open.c:1077 [inline] SyS_open+0x2d/0x40 fs/open.c:1072 entry_SYSCALL_64_fastpath+0x1f/0xbe Freed by task 9692: 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] kmem_cache_free+0x77/0x280 mm/slab.c:3763 putname+0xee/0x130 fs/namei.c:257 do_sys_open+0x31b/0x6d0 fs/open.c:1068 SYSC_open fs/open.c:1077 [inline] SyS_open+0x2d/0x40 fs/open.c:1072 entry_SYSCALL_64_fastpath+0x1f/0xbe The buggy address belongs to the object at ffff8800371b8480 which belongs to the cache names_cache of size 4096 The buggy address is located 2498 bytes inside of 4096-byte region [ffff8800371b8480, ffff8800371b9480) The buggy address belongs to the page: page:ffffea0000dc6e00 count:1 mapcount:0 mapping:ffff8800371b8480 index:0x0 compound_mapcount: 0 flags: 0x100000000008100(slab|head) raw: 0100000000008100 ffff8800371b8480 0000000000000000 0000000100000001 raw: ffffea0000d91aa0 ffffea0000de75a0 ffff88003e87c200 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8800371b8d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8800371b8d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8800371b8e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8800371b8e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8800371b8f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================