求大神解答，这个错误报告什么情况！

Process: dota_osx [409]
Path: /Users/USER/Library/Application Support/Steam/*/dota_osx
Identifier: dota_osx
Version: ???
Code Type: X86 (Native)
Parent Process: bash [406]
Responsible: bash [321]
User ID: 501
Date/Time: 2014-04-30 18:46:23.530 +0200
OS Version: Mac OS X 10.9.2 (13C64)
Report Version: 11
Anonymous UUID: CCC30F26-6441-AC52-7CFA-2C3220F4F5F8
Crashed Thread: 20
Exception Type: EXC_BAD_ACCESS (SIGBUS)
Exception Codes: KERN_PROTECTION_FAILURE at 0x0000000000000000
VM Regions Near 0:
--> __PAGEZERO 0000000000000000-0000000000001000 [ 4K] ---/--- SM=NUL /Users/USER/Library/Application Support/Steam/*
VM_ALLOCATE 0000000000001000-00000000000b7000 [ 728K] ---/--- SM=NUL