We need to check for stack overflow only when the signal is on stack. So we can improve the patch "http://lkml.org/lkml/2007/11/27/101" as following.
Signed-off-by: Shi Weihua <[EMAIL PROTECTED]> --- The previous patch has a comment mistake. Now I correct it. --- --- linux-2.6.25-rc2.orig/arch/x86/kernel/signal_32.c 2008-02-16 04:57:20.000000000 +0800 +++ linux-2.6.25-rc2/arch/x86/kernel/signal_32.c 2008-02-19 09:55:59.000000000 +0800 @@ -299,17 +299,21 @@ get_sigframe(struct k_sigaction *ka, str /* Default to using normal stack */ sp = regs->sp; - /* - * If we are on the alternate signal stack and would overflow it, don't. - * Return an always-bogus address instead so we will die with SIGSEGV. - */ - if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size))) - return (void __user *) -1L; - /* This is the X/Open sanctioned signal stack switching. */ if (ka->sa.sa_flags & SA_ONSTACK) { - if (sas_ss_flags(sp) == 0) + int onstack = sas_ss_flags(sp); + + if (onstack == 0) sp = current->sas_ss_sp + current->sas_ss_size; + else if (onstack == SS_ONSTACK) { + /* + * If we are on the alternate signal stack and would + * overflow it, don't. Return an always-bogus address + * instead so we will die with SIGSEGV. + */ + if (!likely(on_sig_stack(sp - frame_size))) + return (void __user *) -1L; + } } /* This is the legacy signal stack switching. */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/