[PATCH] Signal hadnling fix for 2.4

[Paul Mackerras]

Stephen Rothwell writes:

> While investigating a bug report about a 64bit application that crashed in
> malloc, Paul Mackerras noticed that sys_rt_sigreturn's return value was
> "int".  It needs to be "long" or else the return value of a syscall that
> is interrupted by a signal will be truncated to 32 bits and then sign
> extended.  This causes .e.g mmap's return value to be corrupted if it is
> returning an address above 2^31 (which is what caused a SEGV in malloc).
> This problem obviously only affects 64 bit processes.
> 
> Signed-off-by: Stephen Rothwell <sfr at canb.auug.org.au>

Acked-by: Paul Mackerras <paulus at samba.org>