Re: New setre*id functions broken on alpha

[Jakub Jelinek <jakub at redhat dot com>]

On Mon, Nov 01, 2004 at 08:02:39AM +0100, Jakub Jelinek wrote:
> On Sun, Oct 31, 2004 at 12:02:03AM +0200, Mariusz Mazur wrote:
> > Stub functions aren't used any more, now C compiler has controll of the what's 
> > going on. Those functions take gid_t or uid_t as arguments and those types 
> > are defines as unsigned int (32 bit). Later they are casted to type long to 
> > put them into appropriate registers before making a syscall. The problem is 
> > that although those are unsigned ints we're using, the kernel expects to get 
> > a '-1' value in some cases (ask the designers what where they thinking). Now 
> > according to "Calling Standard for Alpha Systems"* when passing a 32bit 
> > signed to a function (that is putting it into a 64bit register) the signed 
> 
> But uid_t is unsigned int on Alpha:
> 
> asm-alpha/posix_types.h:typedef unsigned int  __kernel_uid_t;
> asm-alpha/posix_types.h:typedef __kernel_uid_t __kernel_uid32_t;
> linux/types.h:typedef __kernel_uid32_t        uid_t;
> 
> asmlinkage long sys_setreuid(uid_t ruid, uid_t euid)
> ...
>         if (ruid != (uid_t) -1) {
> ...
>         if (euid != (uid_t) -1) {

But even unsigned int is sign-extended on Alpha:
   For Alpha, we always store objects in a full register.  32-bit integers
   are always sign-extended, but smaller objects retain their signedness.
#define PROMOTE_MODE(MODE,UNSIGNEDP,TYPE)                       \
  if (GET_MODE_CLASS (MODE) == MODE_INT                         \
      && (TYPE == NULL || TREE_CODE (TYPE) != VECTOR_TYPE)      \
      && GET_MODE_SIZE (MODE) < UNITS_PER_WORD)                 \
    {                                                           \
      if ((MODE) == SImode)                                     \
        (UNSIGNEDP) = 0;                                        \
      (MODE) = DImode;                                          \
    }

In that case I think more INLINE_SYSCALL/INTERNAL_SYSCALL invocations
need to be audited...

	Jakub