[Vol-users] linux syscall table

Hi, I am trying to make some check on a linux server with kernel 2.6.18. I am not a kernel developer so I don't know if what I am going to say is wrong...anyway. # ./vol.py -f /root/image_mem/AAA.lime --profile=LinuxAAAx86 linux_check_syscall Volatility Foundation Volatility Framework 2.3.1 Table Name Index Address Symbol ---------- ---------- ---------- ------------------------------ 32bit 0x0 0xc0430543 sys_restart_syscall 32bit 0x1 0xc0428888 sys_exit 32bit 0x2 0xc0403190 sys_fork 32bit 0x3 0xc0478826 sys_read ..... SNIP 32bit 0xe 0xc04872bf sys_mknod 32bit 0xf 0xc0476cb8 sys_chmod 32bit 0x10 0xc043cef7 sys_lchown16 32bit 0x11 0xc0437304 compat_sys_futex 32bit 0x12 0xc04808e0 sys_stat 32bit 0x13 0xc047873f sys_lseek 32bit 0x14 0xc042e69f sys_getpid ..... SNIP 32bit 0x13f 0xc0437304 compat_sys_futex 32bit 0x140 0xc0437304 compat_sys_futex 32bit 0x141 0xc0437304 compat_sys_futex 32bit 0x142 0xc0437304 compat_sys_futex 32bit 0x143 0xc049e91f sys_eventfd 32bit 0x144 0xc047691d sys_fallocate 32bit 0x145 0xc0437304 compat_sys_futex 32bit 0x146 0xc0437304 compat_sys_futex 32bit 0x147 0xc0437304 compat_sys_futex 32bit 0x148 0xc0437304 compat_sys_futex 32bit 0x149 0xc0437304 compat_sys_futex 32bit 0x14a 0xc0437304 compat_sys_futex 32bit 0x14b 0xc0437304 compat_sys_futex 32bit 0x14c 0xc0437304 compat_sys_futex 32bit 0x14d 0xc0437304 compat_sys_futex 32bit 0x14e 0xc0437304 compat_sys_futex 32bit 0x14f 0xc0437304 compat_sys_futex 32bit 0x150 0xc0437304 compat_sys_futex 32bit 0x151 0xc05be378 sys_recvmmsg What is this compat_sys_futex ??? I don't find anything like that on kernel source linux-2.6.18/arch/i386/kernelsyscall_table.S compat_sys_futex 32bit 0xf 0xc0476cb8 sys_chmod 32bit 0x10 0xc043cef7 sys_lchown16 32bit 0x11 0xc0437304 compat_sys_futex 32bit 0x12 0xc04808e0 sys_stat 32bit 0x13 0xc047873f sys_lseek should be sys_ni_syscallall .long sys_chmod /* 15 */ .long sys_lchown16 .long sys_ni_syscall /* old break syscall holder */ .long sys_stat .long sys_lseek but... # ./vol.py -f /root/image_mem/AAA.lime --profile=LinuxAAAx86 linux_check_syscall | grep compat_sys_futex | wc -l Volatility Foundation Volatility Framework 2.3.1 41 # and $ grep sys_ni_syscall syscall_table.S | wc -l 21 ?!?!? Anyone have enough patience to explain me this anomaly ? Or this is a syscall hijacking ? An other question... Is it normal that in the idt is missing "double fault" ?? # ./vol.py -f /root/image_mem/AAA.lime --profile=LinuxAAAx86 linux_check_idt Volatility Foundation Volatility Framework 2.3.1 Index Address Symbol ---------- ---------- ------------------------------ 0x0 0xc0405a7c divide_error 0x1 0xc0625498 debug 0x2 0xc0405b14 nmi 0x3 0xc06254dc int3 0x4 0xc0405c04 overflow 0x5 0xc0405c10 bounds 0x6 0xc0405c1c invalid_op 0x7 0xc0405adc device_not_available 0x9 0xc0405c28 coprocessor_segment_overrun 0xa 0xc0405c34 invalid_TSS 0xb 0xc0405c40 segment_not_present 0xc 0xc0405c4c stack_segment 0xd 0xc0625500 general_protection 0xe 0xc062550c page_fault 0xf 0xc0405c74 spurious_interrupt_bug 0x10 0xc0405ac4 coprocessor_error 0x11 0xc0405c58 alignment_check 0x12 0xc0405c64 machine_check 0x13 0xc0405ad0 simd_coprocessor_error 0x80 0xc0404f04 system_call where is 0x8 ? Thank you very much.