X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=qemu%2Froms%2Fipxe%2Fsrc%2Farch%2Fi386%2Fcore%2Fnulltrap.c;fp=qemu%2Froms%2Fipxe%2Fsrc%2Farch%2Fi386%2Fcore%2Fnulltrap.c;h=3046fbecf2298f97ec6f38f882914325077bd81a;hb=e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb;hp=0000000000000000000000000000000000000000;hpb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;p=kvmfornfv.git diff --git a/qemu/roms/ipxe/src/arch/i386/core/nulltrap.c b/qemu/roms/ipxe/src/arch/i386/core/nulltrap.c new file mode 100644 index 000000000..3046fbecf --- /dev/null +++ b/qemu/roms/ipxe/src/arch/i386/core/nulltrap.c @@ -0,0 +1,51 @@ +#include +#include + +__attribute__ (( noreturn, section ( ".text.null_trap" ) )) +void null_function_trap ( void ) { + void *stack; + + /* 128 bytes of NOPs; the idea of this is that if something + * dereferences a NULL pointer and overwrites us, we at least + * have some chance of still getting to execute the printf() + * statement. + */ + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + __asm__ __volatile__ ( "nop ; nop ; nop ; nop" ); + + __asm__ __volatile__ ( "movl %%esp, %0" : "=r" ( stack ) ); + printf ( "NULL method called from %p (stack %p)\n", + __builtin_return_address ( 0 ), stack ); + DBG_HD ( stack, 256 ); + while ( 1 ) {} +}