From: Bernhard Walle <bwalle@suse.de>
Date: Sun, 28 Jan 2007 12:47:02 +0000 (+0100)
Subject: [IA64] Fix NULL-pointer dereference in ia64_machine_kexec()
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c2c77fe8df3e0322a613ba1540910632ad14d96d;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

[IA64] Fix NULL-pointer dereference in ia64_machine_kexec()

This patch fixes a NULL-pointer dereference in ia64_machine_kexec().

The variable ia64_kimage is set in machine_kexec_prepare() which is
called from sys_kexec_load(). If kdump wasn't configured before,
ia64_kimage is NULL.  machine_kdump_on_init() passes ia64_kimage() to
machine_kexec() which assumes a valid value.

The patch also adds a few sanity checks for the image to simplify
debugging of similar problems in future.

Signed-off-by: Bernhard Walle <bwalle@suse.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
---

diff --git a/arch/ia64/kernel/crash.c b/arch/ia64/kernel/crash.c
index 2018e624f5e2..9d92097ce96d 100644
--- a/arch/ia64/kernel/crash.c
+++ b/arch/ia64/kernel/crash.c
@@ -118,6 +118,11 @@ machine_crash_shutdown(struct pt_regs *pt)
 static void
 machine_kdump_on_init(void)
 {
+	if (!ia64_kimage) {
+		printk(KERN_NOTICE "machine_kdump_on_init(): "
+				"kdump not configured\n");
+		return;
+	}
 	local_irq_disable();
 	kexec_disable_iosapic();
 	machine_kexec(ia64_kimage);
diff --git a/arch/ia64/kernel/machine_kexec.c b/arch/ia64/kernel/machine_kexec.c
index e51cd904a23e..4f0f3b8c1ee2 100644
--- a/arch/ia64/kernel/machine_kexec.c
+++ b/arch/ia64/kernel/machine_kexec.c
@@ -82,6 +82,7 @@ static void ia64_machine_kexec(struct unw_frame_info *info, void *arg)
 	unsigned long vector;
 	int ii;
 
+	BUG_ON(!image);
 	if (image->type == KEXEC_TYPE_CRASH) {
 		crash_save_this_cpu();
 		current->thread.ksp = (__u64)info->sw - 16;
@@ -120,6 +121,7 @@ static void ia64_machine_kexec(struct unw_frame_info *info, void *arg)
 
 void machine_kexec(struct kimage *image)
 {
+	BUG_ON(!image);
 	unw_init_running(ia64_machine_kexec, image);
 	for(;;);
 }