On Wed, Nov 23, 2011 at 11:22 AM, Alexandru Juncu <alex.juncu@xxxxxxxxxx> wrote: > On Wed, Nov 23, 2011 at 10:40 AM, Geraint Yang <geraint0923@xxxxxxxxx> wrote: >> Hello everyone, >> >> I am going to hook a system call like 'read' or 'send' by modifying the >> sys_call_table, but it seems that the sys_call_table is in read only page, >> how can I set modify the sys_call_table ? Or if there any method that I can >> use to hook a system call in module without modify the kernel source? >> >> Thanks! > > On a 2.6.35 kernel, it worked for me just by changing an entry in the > sys_call_table, within a kernel module. Something like this: Alex, I am pretty sure that you are using a hacked version of 2.6.35. Geraint, In order to be able to hook a syscall you must do the following: 1. export syscall_table in arch/x86/kernel/i386_ksyms_32.c extern void* sys_call_table[]; EXPORT_SYMBOL(sys_call_table); 2. make sys_call_table writebale. In arch/x86/kernel/entry_32.S you must have: .section .data,"a" #include "syscall_table_32.S" thanks, Daniel. _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
