================================================================== BUG: KASAN: use-after-free in packet_rcv+0x5aa/0x1490 net/packet/af_packet.c:2104 Read of size 1 at addr ffff8880583730ec by task syz-executor.5/15432 CPU: 0 PID: 15432 Comm: syz-executor.5 Not tainted 4.19.211-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+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load1_noabort+0x88/0x90 mm/kasan/report.c:430 packet_rcv+0x5aa/0x1490 net/packet/af_packet.c:2104 packet_rcv_fanout+0x505/0x6d0 net/packet/af_packet.c:1466 deliver_skb net/core/dev.c:1956 [inline] dev_queue_xmit_nit+0x24d/0xa20 net/core/dev.c:2012 xmit_one net/core/dev.c:3252 [inline] dev_hard_start_xmit+0xaa/0x920 net/core/dev.c:3272 __dev_queue_xmit+0x269d/0x2e00 net/core/dev.c:3838 hsr_xmit net/hsr/hsr_forward.c:237 [inline] hsr_forward_do net/hsr/hsr_forward.c:295 [inline] hsr_forward_skb+0xd2d/0x1c30 net/hsr/hsr_forward.c:373 send_hsr_supervision_frame+0x917/0xf70 net/hsr/hsr_device.c:321 hsr_announce+0x125/0x3a0 net/hsr/hsr_device.c:350 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375 __run_timers kernel/time/timer.c:1696 [inline] run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709 __do_softirq+0x265/0x980 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x215/0x260 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1098 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:__rcu_read_unlock+0x104/0x160 kernel/rcu/tree_plugin.h:430 Code: d2 75 62 8b 83 74 03 00 00 85 c0 75 69 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea 03 0f b6 04 02 84 c0 74 04 3c 03 7e 42 83 70 03 00 00 00 00 00 00 e9 34 ff ff ff 0f 0b 5b 5d c3 48 89 RSP: 0018:ffff8882321c7718 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffff8880b323a280 RCX: ffffffff81518c83 RDX: 1ffff110166474be RSI: 0000000000000004 RDI: ffff8880b323a5f4 RBP: ffff8880b323a5f0 R08: 0000000000000000 R09: ffffed101740455a R10: ffff8880ba022ad3 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: dead000000000100 R15: 00007f5814eed000 rcu_read_unlock include/linux/rcupdate.h:680 [inline] __unlock_page_memcg+0x54/0x100 mm/memcontrol.c:1955 page_remove_rmap+0xe5/0x120 mm/rmap.c:1297 zap_pte_range mm/memory.c:1350 [inline] zap_pmd_range mm/memory.c:1463 [inline] zap_pud_range mm/memory.c:1492 [inline] zap_p4d_range mm/memory.c:1513 [inline] unmap_page_range+0x147d/0x2c50 mm/memory.c:1534 unmap_single_vma+0x198/0x300 mm/memory.c:1579 unmap_vmas+0xa9/0x180 mm/memory.c:1609 exit_mmap+0x2b9/0x530 mm/mmap.c:3093 __mmput kernel/fork.c:1016 [inline] mmput+0x14e/0x4a0 kernel/fork.c:1037 exit_mm kernel/exit.c:549 [inline] do_exit+0xaec/0x2be0 kernel/exit.c:857 do_group_exit+0x125/0x310 kernel/exit.c:967 get_signal+0x3f2/0x1f70 kernel/signal.c:2589 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:799 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f581549cae9 Code: Bad RIP value. RSP: 002b:00007f58143f1218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f58155b0030 RCX: 00007f581549cae9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f58155b0030 RBP: 00007f58155b0028 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f58155b0034 R13: 00007ffce34f585f R14: 00007f58143f1300 R15: 0000000000022000 Allocated by task 15426: __do_kmalloc mm/slab.c:3727 [inline] __kmalloc+0x15a/0x3c0 mm/slab.c:3736 kmalloc include/linux/slab.h:520 [inline] sk_prot_alloc+0x1e2/0x2d0 net/core/sock.c:1483 sk_alloc+0x36/0xec0 net/core/sock.c:1537 packet_create+0x117/0x850 net/packet/af_packet.c:3259 __sock_create+0x3d8/0x740 net/socket.c:1365 sock_create net/socket.c:1416 [inline] __sys_socket+0xef/0x200 net/socket.c:1458 __do_sys_socket net/socket.c:1467 [inline] __se_sys_socket net/socket.c:1465 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1465 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 15419: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 sk_prot_free net/core/sock.c:1520 [inline] __sk_destruct+0x684/0x8a0 net/core/sock.c:1602 sk_destruct net/core/sock.c:1617 [inline] __sk_free+0x165/0x3b0 net/core/sock.c:1628 sk_free+0x3b/0x50 net/core/sock.c:1639 sock_put include/net/sock.h:1713 [inline] packet_release+0x890/0xb70 net/packet/af_packet.c:3088 __sock_release+0xcd/0x2a0 net/socket.c:599 sock_close+0x15/0x20 net/socket.c:1214 __fput+0x2ce/0x890 fs/file_table.c:278 task_work_run+0x148/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880583729c0 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 1836 bytes inside of 4096-byte region [ffff8880583729c0, ffff8880583739c0) The buggy address belongs to the page: page:ffffea000160dc80 count:1 mapcount:0 mapping:ffff88813bff0dc0 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea000235b888 ffffea000283cf88 ffff88813bff0dc0 raw: 0000000000000000 ffff8880583729c0 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888058372f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888058373000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888058373080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888058373100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888058373180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: d2 75 62 shlb %cl,0x62(%rbp) 3: 8b 83 74 03 00 00 mov 0x374(%rbx),%eax 9: 85 c0 test %eax,%eax b: 75 69 jne 0x76 d: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 14: fc ff df 17: 48 89 ea mov %rbp,%rdx 1a: 48 c1 ea 03 shr $0x3,%rdx 1e: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax 22: 84 c0 test %al,%al 24: 74 04 je 0x2a 26: 3c 03 cmp $0x3,%al 28: 7e 42 jle 0x6c * 2a: c7 83 70 03 00 00 00 movl $0x0,0x370(%rbx) <-- trapping instruction 31: 00 00 00 34: e9 34 ff ff ff jmpq 0xffffff6d 39: 0f 0b ud2 3b: 5b pop %rbx 3c: 5d pop %rbp 3d: c3 retq 3e: 48 rex.W 3f: 89 .byte 0x89