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From: Baoquan He <bhe@redhat.com>
To: hpa@zytor.com, yinghai@kernel.org, keescook@chromium.org,
	vgoyal@redhat.com, luto@amacapital.net,
	akpm@linux-foundation.org, tglx@linutronix.de, mingo@redhat.com
Cc: linux-kernel@vger.kernel.org, Baoquan He <bhe@redhat.com>
Subject: [PATCH v2 5/9] add mem_min_overlap to find the first avoid region within a memory region
Date: Mon,  2 Mar 2015 22:58:26 +0800	[thread overview]
Message-ID: <1425308310-2318-6-git-send-email-bhe@redhat.com> (raw)
In-Reply-To: <1425308310-2318-1-git-send-email-bhe@redhat.com>

Given a memory region mem_min_overlap will iterate all avoid region
to find the first one which overlap with it. This function will be
used later.

Signed-off-by: Baoquan He <bhe@redhat.com>
---
 arch/x86/boot/compressed/aslr.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/arch/x86/boot/compressed/aslr.c b/arch/x86/boot/compressed/aslr.c
index 26610a2..ded3959 100644
--- a/arch/x86/boot/compressed/aslr.c
+++ b/arch/x86/boot/compressed/aslr.c
@@ -213,6 +213,38 @@ static bool mem_avoid_overlap(struct mem_vector *img)
 	return false;
 }
 
+static unsigned long mem_min_overlap(struct mem_vector *img, struct mem_vector *out)
+{
+	int i;
+	struct setup_data *ptr;
+	unsigned long min = img->start + img->size;
+
+	for (i = 0; i < MEM_AVOID_MAX; i++) {
+		if (mem_overlaps(img, &mem_avoid[i]) && (mem_avoid[i].start < min) ) {
+			*out = mem_avoid[i];
+			min = mem_avoid[i].start;
+		}
+	}
+
+	/* Check all entries in the setup_data linked list. */
+	ptr = (struct setup_data *)(unsigned long)real_mode->hdr.setup_data;
+	while (ptr) {
+		struct mem_vector avoid;
+
+		avoid.start = (unsigned long)ptr;
+		avoid.size = sizeof(*ptr) + ptr->len;
+
+		if (mem_overlaps(img, &avoid) && (avoid.start < min) ) {
+			*out = avoid;
+			min = avoid.start;
+		}
+
+		ptr = (struct setup_data *)(unsigned long)ptr->next;
+	}
+
+	return min;
+}
+
 static unsigned long slots[CONFIG_RANDOMIZE_BASE_MAX_OFFSET /
 			   CONFIG_PHYSICAL_ALIGN];
 
-- 
1.9.3


  parent reply	other threads:[~2015-03-02 14:59 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-02 14:58 [PATCH v2 0/9] randomize kernel physical address and virtual address separately Baoquan He
2015-03-02 14:58 ` [PATCH v2 1/9] remove a unused function parameter Baoquan He
2015-03-03 18:32   ` Yinghai Lu
2015-03-04 15:48     ` Baoquan He
2015-03-02 14:58 ` [PATCH v2 2/9] a bug that relocation can not be handled when kernel is loaded above 2G Baoquan He
2015-03-02 14:58 ` [PATCH v2 3/9] make kernel be able to load above 4G in boot stage Baoquan He
2015-03-02 15:58   ` Baoquan He
2015-03-02 14:58 ` [PATCH v2 4/9] introduce struct slot_area to manage randomization slot info Baoquan He
2015-03-02 14:58 ` Baoquan He [this message]
2015-03-02 14:58 ` [PATCH v2 6/9] change process_e820_entry to store slot info into slot_area Baoquan He
2015-03-02 14:58 ` [PATCH v2 7/9] get the random phy addr according to slot_area info Baoquan He
2015-03-03  8:45   ` Yinghai Lu
2015-03-03 11:42     ` Baoquan He
2015-03-03 16:14       ` Yinghai Lu
2015-03-04 12:08         ` Baoquan He
2015-03-04 15:39     ` Baoquan He
2015-03-04 21:35       ` Yinghai Lu
2015-03-05  0:12         ` Yinghai Lu
2015-03-05  1:55           ` Baoquan He
2015-03-05  0:30       ` Yinghai Lu
2015-03-05  1:48         ` Baoquan He
2015-03-04 21:28   ` Kees Cook
2015-03-04 23:43     ` Baoquan He
2015-03-02 14:58 ` [PATCH v2 8/9] introduce fetch_random_virt_offset to randomize the kernel text mapping address Baoquan He
2015-03-02 14:58 ` [PATCH v2 9/9] change the relocations behavior for kaslr on x86_64 Baoquan He
2015-03-04 23:16   ` Yinghai Lu
2015-03-04 23:41     ` Baoquan He
2015-03-05 15:57 ` [PATCH v2 0/9] randomize kernel physical address and virtual address separately Baoquan He
2015-03-06  1:37   ` Yinghai Lu

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