From 5f15256acab27859ececcfda1b882e8c49597697 Mon Sep 17 00:00:00 2001

From: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>

Date: Tue, 20 Oct 2015 16:08:01 +0900

Subject: [PATCH 1/2] [PATCH 1/2] sadump: Change bit order.

sadump formats associate each bit in a bitmap with a physical

page in reverse order with the kdump-compressed format.

We had not detected this bug for considerably long term because

bitmaps in sadump formats consist mostly of 0x00 and 0xff excluding a

very limited amount of memory space for firmware.

Signed-off-by: Takao Indoh <indou.takao@jp.fujitsu.com>

Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>

---

 makedumpfile-1.5.7/sadump_info.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++--

 1 file changed, 73 insertions(+), 2 deletions(-)

diff --git a/makedumpfile-1.5.7/sadump_info.c b/makedumpfile-1.5.7/sadump_info.c

index 23275e2..4740683 100644

--- a/makedumpfile-1.5.7/sadump_info.c

+++ b/makedumpfile-1.5.7/sadump_info.c

@@ -85,6 +85,7 @@ struct sadump_info {

 	unsigned long long backup_offset;

 	int kdump_backed_up;

 	mdf_pfn_t max_mapnr;

+	struct dump_bitmap *ram_bitmap;

 };

 static char *guid_to_str(efi_guid_t *guid, char *buf, size_t buflen);

@@ -127,6 +128,35 @@ static int get_registers(int cpu, struct elf_prstatus *prstatus);

 static struct sadump_info sadump_info = {};

 static struct sadump_info *si = &sadump_info;

+static inline int

+sadump_is_on(char *bitmap, mdf_pfn_t i)

+{

+	return bitmap[i >> 3] & (1 << (7 - (i & 7)));

+}

+

+static inline int

+sadump_is_dumpable(struct dump_bitmap *bitmap, mdf_pfn_t pfn)

+{

+	off_t offset;

+

+	if (pfn == 0 || bitmap->no_block != pfn/PFN_BUFBITMAP) {

+		offset = bitmap->offset + BUFSIZE_BITMAP*(pfn/PFN_BUFBITMAP);

+		lseek(bitmap->fd, offset, SEEK_SET);

+		read(bitmap->fd, bitmap->buf, BUFSIZE_BITMAP);

+		if (pfn == 0)

+			bitmap->no_block = 0;

+		else

+			bitmap->no_block = pfn / PFN_BUFBITMAP;

+	}

+	return sadump_is_on(bitmap->buf, pfn % PFN_BUFBITMAP);

+}

+

+static inline int

+sadump_is_ram(mdf_pfn_t pfn)

+{

+	return sadump_is_dumpable(si->ram_bitmap, pfn);

+}

+

 int

 check_and_get_sadump_header_info(char *filename)

 {

@@ -161,6 +191,21 @@ check_and_get_sadump_header_info(char *filename)

 	return TRUE;

 }

+static void

+reverse_bit(char *buf, int len)

+{

+	int i;

+	unsigned char c;

+

+	for (i = 0; i < len; i++) {

+		c = buf[i];

+		c = ((c & 0x55) << 1) | ((c & 0xaa) >> 1); /* Swap 1bit */

+		c = ((c & 0x33) << 2) | ((c & 0xcc) >> 2); /* Swap 2bit */

+		c = (c << 4) | (c >> 4); /* Swap 4bit */

+		buf[i] = c;

+	}

+}

+

 int

 sadump_copy_1st_bitmap_from_memory(void)

 {

@@ -189,6 +234,14 @@ sadump_copy_1st_bitmap_from_memory(void)

 			       info->name_memory, strerror(errno));

 			return FALSE;

 		}

+		/*

+		 * sadump formats associate each bit in a bitmap with

+		 * a physical page in reverse order with the

+		 * kdump-compressed format. We need to change bit

+		 * order to reuse bitmaps in sadump formats in the

+		 * kdump-compressed format.

+		 */

+		reverse_bit(buf, sizeof(buf));

 		if (write(info->bitmap1->fd, buf, sizeof(buf)) != sizeof(buf)) {

 			ERRMSG("Can't write the bitmap(%s). %s\n",

 			       info->bitmap1->file_name, strerror(errno));

@@ -808,6 +861,19 @@ sadump_initialize_bitmap_memory(void)

 	info->bitmap_memory = bmp;

 	si->block_table = block_table;

+	bmp = malloc(sizeof(struct dump_bitmap));

+	if (bmp == NULL) {

+		ERRMSG("Can't allocate memory for the memory-bitmap. %s\n",

+		       strerror(errno));

+		return FALSE;

+	}

+	bmp->fd = info->fd_memory;

+	bmp->file_name = info->name_memory;

+	bmp->no_block = -1;

+	memset(bmp->buf, 0, BUFSIZE_BITMAP);

+	bmp->offset = si->sub_hdr_offset + sh->block_size * sh->sub_hdr_size;

+	si->ram_bitmap = bmp;

+

 	return TRUE;

 }

@@ -977,7 +1043,12 @@ readpage_sadump(unsigned long long paddr, void *bufptr)

 	if (pfn >= si->max_mapnr)

 		return FALSE;

-	if (!is_dumpable(info->bitmap_memory, pfn)) {

+	if (!sadump_is_ram(pfn)) {

+		ERRMSG("pfn(%llx) is not ram.\n", pfn);

+		return FALSE;

+	}

+

+	if (!sadump_is_dumpable(info->bitmap_memory, pfn)) {

 		ERRMSG("pfn(%llx) is excluded from %s.\n", pfn,

 		       info->name_memory);

 		return FALSE;

@@ -1142,7 +1213,7 @@ pfn_to_block(mdf_pfn_t pfn)

 		block = 0;

 	for (p = section * SADUMP_PF_SECTION_NUM; p < pfn; ++p)

-		if (is_dumpable(info->bitmap_memory, p))

+		if (sadump_is_dumpable(info->bitmap_memory, p))

 			block++;

 	return block;

-- 

2.1.0