linux-kernel - [RFC PATCH -tip 08/16] x86/kprobes: Recover breakpoint instruction if KGDB knows

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]

Message-ID: <20120401160341.4502.28323.stgit@shimauta>
Date:	Mon, 02 Apr 2012 01:03:41 +0900
From:	Masami Hiramatsu <masami.hiramatsu@...il.com>
To:	linux-kernel@...r.kernel.org
Cc:	Huang Ying <ying.huang@...el.com>,
	Ananth N Mavinakayanahalli <ananth@...ibm.com>,
	Frederic Weisbecker <fweisbec@...il.com>,
	"H. Peter Anvin" <hpa@...or.com>, Ingo Molnar <mingo@...hat.com>,
	Jason Wessel <jason.wessel@...driver.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>
Subject: [RFC PATCH -tip 08/16] x86/kprobes: Recover breakpoint instruction if
 KGDB knows

Recover a breakpoint instruction which KGDB has put.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu@...il.com>
---
 arch/x86/kernel/kprobes.c |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c
index e213fc8..ddd21b8 100644
--- a/arch/x86/kernel/kprobes.c
+++ b/arch/x86/kernel/kprobes.c
@@ -49,6 +49,7 @@
 #include <linux/kdebug.h>
 #include <linux/kallsyms.h>
 #include <linux/ftrace.h>
+#include <linux/kgdb.h>
 
 #include <asm/cacheflush.h>
 #include <asm/desc.h>
@@ -252,6 +253,14 @@ unsigned long recover_probed_instruction(kprobe_opcode_t *buf, unsigned long add
 {
 	unsigned long __addr;
 
+#ifdef CONFIG_KGDB
+	/* Recover if kgdb has put a breakpoint */
+	if (kgdb_get_saved_instr(addr, buf)) {
+		memcpy(buf + BREAK_INSTR_SIZE, (void *)addr + BREAK_INSTR_SIZE,
+			(MAX_INSN_SIZE - BREAK_INSTR_SIZE) * sizeof(kprobe_opcode_t));
+		return (unsigned long)buf;
+	}
+#endif
 	__addr = __recover_optprobed_insn(buf, addr);
 	if (__addr != addr)
 		return __addr;

--
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/