linux-kernel - [PATCH] IA64 signal : remove redundant code in setup

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <4740F07E.1010301@cn.fujitsu.com>
Date:	Mon, 19 Nov 2007 10:10:06 +0800
From:	Shi Weihua <shiwh@...fujitsu.com>
To:	linux-kernel@...r.kernel.org
Subject: [PATCH] IA64 signal : remove redundant code in setup_sigcontext()

This patch removes some redundant code in the function setup_sigcontext().

The registers ar.ccv,b7,r14,ar.csd,ar.ssd,r2-r3 and r16-r31 are not restored 
in restore_sigcontext() when (flags & IA64_SC_FLAG_IN_SYSCALL) is true. 
So we don't need to zero those variables in setup_sigcontext().

Signed-off-by: Shi Weihua <shiwh@...fujitsu.com> 

---
diff  -urp linux-2.6.24-rc2.orig/arch/ia64/kernel/signal.c linux-2.6.24-rc2/arch/ia64/kernel/signal.c
--- linux-2.6.24-rc2.orig/arch/ia64/kernel/signal.c	2007-11-09 14:38:53.000000000 +0800
+++ linux-2.6.24-rc2/arch/ia64/kernel/signal.c	2007-11-13 13:30:00.000000000 +0800
@@ -280,15 +280,7 @@ setup_sigcontext (struct sigcontext __us
 	err |= __copy_to_user(&sc->sc_gr[15], &scr->pt.r15, 8);		/* r15 */
 	err |= __put_user(scr->pt.cr_iip + ia64_psr(&scr->pt)->ri, &sc->sc_ip);
 
-	if (flags & IA64_SC_FLAG_IN_SYSCALL) {
-		/* Clear scratch registers if the signal interrupted a system call. */
-		err |= __put_user(0, &sc->sc_ar_ccv);				/* ar.ccv */
-		err |= __put_user(0, &sc->sc_br[7]);				/* b7 */
-		err |= __put_user(0, &sc->sc_gr[14]);				/* r14 */
-		err |= __clear_user(&sc->sc_ar25, 2*8);			/* ar.csd & ar.ssd */
-		err |= __clear_user(&sc->sc_gr[2], 2*8);			/* r2-r3 */
-		err |= __clear_user(&sc->sc_gr[16], 16*8);			/* r16-r31 */
-	} else {
+	if (!(flags & IA64_SC_FLAG_IN_SYSCALL)) {
 		/* Copy scratch regs to sigcontext if the signal didn't interrupt a syscall. */
 		err |= __put_user(scr->pt.ar_ccv, &sc->sc_ar_ccv);		/* ar.ccv */
 		err |= __put_user(scr->pt.b7, &sc->sc_br[7]);			/* b7 */






-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/