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diff -aur qemu-0.8.2.orig/block.c qemu-0.8.2/block.c
--- qemu-0.8.2.orig/block.c 2009-05-03 20:08:39.000000000 +0000
+++ qemu-0.8.2/block.c 2009-05-03 21:18:57.000000000 +0000
@@ -269,6 +269,7 @@
{
int ret;
char tmp_filename[1024];
+ struct stat st;
bs->read_only = 0;
bs->is_temporary = 0;
@@ -336,6 +337,11 @@
goto fail;
}
+ /* Block devices should never be growable. */
+ if (stat(filename, &st) >= 0 && !S_ISCHR(st.st_mode) && !S_ISBLK(st.st_mode)) {
+ bs->growable = 1;
+ }
+
bs->inserted = 1;
/* call the change callback */
@@ -415,6 +421,32 @@
return 0;
}
+static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
+ size_t size)
+{
+ if (bs->growable)
+ return 0;
+
+ if ((offset + size) > (bs->total_sectors * 512))
+ return -1;
+
+ return 0;
+}
+
+static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num,
+ int nb_sectors)
+{
+ int64_t offset;
+
+ /* Deal with byte accesses */
+ if (sector_num < 0)
+ offset = -sector_num;
+ else
+ offset = sector_num * 512;
+
+ return bdrv_check_byte_request(bs, offset, nb_sectors * 512);
+}
+
/* return -1 if error */
int bdrv_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
@@ -424,6 +456,8 @@
if (!bs->inserted)
return -1;
+ if (bdrv_check_request(bs, sector_num, nb_sectors))
+ return -1;
while (nb_sectors > 0) {
if (sector_num == 0 && bs->boot_sector_enabled) {
@@ -464,6 +498,8 @@
return -1;
if (sector_num < 0)
return -1;
+ if (bdrv_check_request(bs, sector_num, nb_sectors))
+ return -1;
if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
memcpy(bs->boot_sector_data, buf, 512);
}
diff -aur qemu-0.8.2.orig/block_int.h qemu-0.8.2/block_int.h
--- qemu-0.8.2.orig/block_int.h 2006-07-22 17:23:34.000000000 +0000
+++ qemu-0.8.2/block_int.h 2009-05-03 21:18:57.000000000 +0000
@@ -67,6 +67,9 @@
int is_temporary;
BlockDriverState *backing_hd;
+
+ /* Whether the disk can expand beyond total_sectors */
+ int growable;
/* NOTE: the following infos are only hints for real hardware
drivers. They are not used by the block driver */
|
