On Thu, May 15, 2014 at 02:31:40PM -0700, Andi Kleen wrote: > Erik Bosman <e...@minemu.org> writes: > > > > > diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c > > index 2206757..1a9285a 100644 > > --- a/arch/x86/ia32/ia32_signal.c > > +++ b/arch/x86/ia32/ia32_signal.c > > @@ -212,9 +212,18 @@ asmlinkage long sys32_sigreturn(void) > > struct sigframe_ia32 __user *frame = (struct sigframe_ia32 __user > > *)(regs->sp-8); > > sigset_t set; > > unsigned int ax; > > +#ifdef CONFIG_SIGNAL_CANARY > > + u32 canary; > > +#endif > > Don't you completely break the ABI here? I'm sure there are programs out > there who hard code the offset into the FP state. > > I think you either need to put it at the total end or somewhere > currently unused >
Hrmz.. FP state is aligned on a 64 byte boundary, the signal frame (separately) on a 16 byte-sizeof(long) boundary. But it looks like that for 32 and 64 bit rt_sigreturn this means no padding :-/ It looks like I'll have to put the canary beyond the fp state. :-( I had hoped to avoid pointer arithmetic. :-/ Erik > Besides that I would remove the CONFIG_* once it works and just do it > unconditionally. > > -Andi > > > -- > a...@linux.intel.com -- Speaking for myself only > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
