linux-kernel - [RFC PATCH v4 20/34] ftrace/x86: Ensure rec->flags no change when failure occures.

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

Date:	Mon, 2 Mar 2015 22:24:58 +0800
From:	Wang Nan <wangnan0@...wei.com>
To:	<rostedt@...dmis.org>, <masami.hiramatsu.pt@...achi.com>,
	<mingo@...e.hu>, <linux@....linux.org.uk>, <tixy@...aro.org>
CC:	<lizefan@...wei.com>, <linux-kernel@...r.kernel.org>,
	<x86@...nel.org>, <linux-arm-kernel@...ts.infradead.org>
Subject: [RFC PATCH v4 20/34] ftrace/x86: Ensure rec->flags no change when failure occures.

Don't change rec->flags if code modification fails.

Signed-off-by: Wang Nan <wangnan0@...wei.com>
---
 arch/x86/kernel/ftrace.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 8b7b0a5..7bdba65 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -497,6 +497,7 @@ static int finish_update(struct dyn_ftrace *rec, int enable)
 {
 	unsigned long ftrace_addr;
 	int ret;
+	unsigned long old_flags = rec->flags;
 
 	ret = ftrace_update_record(rec, enable);
 
@@ -509,14 +510,18 @@ static int finish_update(struct dyn_ftrace *rec, int enable)
 	case FTRACE_UPDATE_MODIFY_CALL:
 	case FTRACE_UPDATE_MAKE_CALL:
 		/* converting nop to call */
-		return finish_update_call(rec, ftrace_addr);
+		ret = finish_update_call(rec, ftrace_addr);
+		break;
 
 	case FTRACE_UPDATE_MAKE_NOP:
 		/* converting a call to a nop */
-		return finish_update_nop(rec);
+		ret = finish_update_nop(rec);
+		break;
 	}
 
-	return 0;
+	if (ret)
+		rec->flags = old_flags;
+	return ret;
 }
 
 static void do_sync_core(void *data)
-- 
1.8.4

--
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/