Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753404Ab3CKOY6 (ORCPT ); Mon, 11 Mar 2013 10:24:58 -0400 Received: from mail9.hitachi.co.jp ([133.145.228.44]:59476 "EHLO mail9.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751266Ab3CKOYd (ORCPT ); Mon, 11 Mar 2013 10:24:33 -0400 X-AuditID: 85900ec0-d1ac5b900000151e-56-513de91eee72 Subject: [PATCH -tip ] [BUGFIX] kprobes: Move hash_64() into .text.kprobe section To: Ingo Molnar , linux-kernel@vger.kernel.org From: Masami Hiramatsu Cc: Timo Juhani Lindfors , Ananth N Mavinakayanahalli , Pavel Emelyanov , Jiri Kosina , Nadia Yvette Chambers , yrl.pp-manager.tt@hitachi.com, "David S. Miller" Date: Mon, 11 Mar 2013 23:22:33 +0900 Message-ID: <20130311142233.19885.10567.stgit@mhiramat-M0-7522> User-Agent: StGit/0.15 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2195 Lines: 66 Beacuse hash_64() is called from the get_kprobe() inside int3 handler, kernel causes int3 recursion and crashes if kprobes user puts a probe on it. Usually hash_64() is inlined into caller function, but in some cases, it has instances by gcc's interprocedural constant propagation. This patch adds __kprobes tag on the hash_64() and moves all those instances into .text.kprobe section so that kprobes can refuse probing on the instances. I've ensured that all hash_64 instances moves to the address between __kprobes_text_start and __kprobes_text_end with this patch as below. ffffffff8138bea0 T __kprobes_text_start ffffffff8138bec0 t hash_64.constprop.8 ffffffff8138ef98 t hash_64.constprop.26 ffffffff8138efae t hash_64 ffffffff8138f066 t hash_64.constprop.43 ffffffff8138f649 t hash_64.constprop.25 ffffffff8139103a t hash_64.constprop.77 ffffffff81391050 t hash_64.constprop.24 ffffffff81391066 t hash_64.constprop.40 ffffffff8139107c t hash_64.constprop.15 ffffffff81391092 T __kprobes_text_end Signed-off-by: Masami Hiramatsu Reported-by: Timo Juhani Lindfors Cc: "David S. Miller" Cc: Nadia Yvette Chambers Cc: Pavel Emelyanov Cc: Jiri Kosina Cc: Ananth N Mavinakayanahalli --- include/linux/hash.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/linux/hash.h b/include/linux/hash.h index 61c97ae..d83f62f 100644 --- a/include/linux/hash.h +++ b/include/linux/hash.h @@ -15,6 +15,7 @@ */ #include +#include /* 2^31 + 2^29 - 2^25 + 2^22 - 2^19 - 2^16 + 1 */ #define GOLDEN_RATIO_PRIME_32 0x9e370001UL @@ -31,7 +32,7 @@ #error Wordsize not 32 or 64 #endif -static inline u64 hash_64(u64 val, unsigned int bits) +static __kprobes inline u64 hash_64(u64 val, unsigned int bits) { u64 hash = val; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/