From 8d54d051da3dd1fd9e7666b7b74b074676c8571f Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Wed, 27 Feb 2008 13:21:36 +0000 Subject: [PATCH] ioemu: Expandable storage backends should defeat block-device range checks. Signed-off-by: Ian Jackson --- tools/ioemu/block-qcow.c | 2 +- tools/ioemu/block-qcow2.c | 2 +- tools/ioemu/block-raw.c | 2 ++ tools/ioemu/block-vmdk.c | 2 +- tools/ioemu/block.c | 17 +++++++++++++---- tools/ioemu/block_int.h | 4 ++++ tools/ioemu/vl.h | 2 ++ 7 files changed, 24 insertions(+), 7 deletions(-) diff --git a/tools/ioemu/block-qcow.c b/tools/ioemu/block-qcow.c index d5333b379d..458450dc08 100644 --- a/tools/ioemu/block-qcow.c +++ b/tools/ioemu/block-qcow.c @@ -95,7 +95,7 @@ static int qcow_open(BlockDriverState *bs, const char *filename, int flags) int len, i, shift, ret; QCowHeader header; - ret = bdrv_file_open(&s->hd, filename, flags); + ret = bdrv_file_open(&s->hd, filename, flags | BDRV_O_EXTENDABLE); if (ret < 0) return ret; if (bdrv_pread(s->hd, 0, &header, sizeof(header)) != sizeof(header)) diff --git a/tools/ioemu/block-qcow2.c b/tools/ioemu/block-qcow2.c index a876ea2e2d..a5f8255389 100644 --- a/tools/ioemu/block-qcow2.c +++ b/tools/ioemu/block-qcow2.c @@ -191,7 +191,7 @@ static int qcow_open(BlockDriverState *bs, const char *filename, int flags) int len, i, shift, ret; QCowHeader header; - ret = bdrv_file_open(&s->hd, filename, flags); + ret = bdrv_file_open(&s->hd, filename, flags | BDRV_O_EXTENDABLE); if (ret < 0) return ret; if (bdrv_pread(s->hd, 0, &header, sizeof(header)) != sizeof(header)) diff --git a/tools/ioemu/block-raw.c b/tools/ioemu/block-raw.c index 182d2ec55e..f0ad65e0a7 100644 --- a/tools/ioemu/block-raw.c +++ b/tools/ioemu/block-raw.c @@ -1489,5 +1489,7 @@ BlockDriver bdrv_host_device = { .bdrv_pread = raw_pread, .bdrv_pwrite = raw_pwrite, .bdrv_getlength = raw_getlength, + + .bdrv_flags = BLOCK_DRIVER_FLAG_EXTENDABLE }; #endif /* _WIN32 */ diff --git a/tools/ioemu/block-vmdk.c b/tools/ioemu/block-vmdk.c index 28df8ae466..0558977abc 100644 --- a/tools/ioemu/block-vmdk.c +++ b/tools/ioemu/block-vmdk.c @@ -352,7 +352,7 @@ static int vmdk_open(BlockDriverState *bs, const char *filename, int flags) uint32_t magic; int l1_size, i, ret; - ret = bdrv_file_open(&s->hd, filename, flags); + ret = bdrv_file_open(&s->hd, filename, flags | BDRV_O_EXTENDABLE); if (ret < 0) return ret; if (bdrv_pread(s->hd, 0, &magic, sizeof(magic)) != sizeof(magic)) diff --git a/tools/ioemu/block.c b/tools/ioemu/block.c index 683dd2e091..c9e27d1191 100644 --- a/tools/ioemu/block.c +++ b/tools/ioemu/block.c @@ -123,20 +123,23 @@ void path_combine(char *dest, int dest_size, static int bdrv_rw_badreq_sectors(BlockDriverState *bs, int64_t sector_num, int nb_sectors) { - return + return ( nb_sectors < 0 || nb_sectors > bs->total_sectors || - sector_num > bs->total_sectors - nb_sectors; + sector_num > bs->total_sectors - nb_sectors + ) && !bs->extendable; } static int bdrv_rw_badreq_bytes(BlockDriverState *bs, int64_t offset, int count) { int64_t size = bs->total_sectors << SECTOR_BITS; - return + return ( count < 0 || count > size || - offset > size - count; + offset > size - count + ) && !bs->extendable; + } void bdrv_register(BlockDriver *bdrv) @@ -347,6 +350,12 @@ int bdrv_open2(BlockDriverState *bs, const char *filename, int flags, bs->is_temporary = 0; bs->encrypted = 0; + if (flags & BDRV_O_EXTENDABLE) { + if (!(drv->bdrv_flags & BLOCK_DRIVER_FLAG_EXTENDABLE)) + return -ENOSYS; + bs->extendable = 1; + } + if (flags & BDRV_O_SNAPSHOT) { BlockDriverState *bs1; int64_t total_size; diff --git a/tools/ioemu/block_int.h b/tools/ioemu/block_int.h index 25f6717b5c..fba27c2c35 100644 --- a/tools/ioemu/block_int.h +++ b/tools/ioemu/block_int.h @@ -24,6 +24,8 @@ #ifndef BLOCK_INT_H #define BLOCK_INT_H +#define BLOCK_DRIVER_FLAG_EXTENDABLE 0x0001u + struct BlockDriver { const char *format_name; int instance_size; @@ -76,6 +78,7 @@ struct BlockDriver { int (*bdrv_eject)(BlockDriverState *bs, int eject_flag); int (*bdrv_set_locked)(BlockDriverState *bs, int locked); + unsigned bdrv_flags; BlockDriverAIOCB *free_aiocb; struct BlockDriver *next; }; @@ -87,6 +90,7 @@ struct BlockDriverState { int removable; /* if true, the media can be removed */ int locked; /* if true, the media cannot temporarily be ejected */ int encrypted; /* if true, the media is encrypted */ + int extendable;/* if true, we may write out of original range */ /* event callback when inserting/removing */ void (*change_cb)(void *opaque); void *change_opaque; diff --git a/tools/ioemu/vl.h b/tools/ioemu/vl.h index c84a60920d..0c5a9da97f 100644 --- a/tools/ioemu/vl.h +++ b/tools/ioemu/vl.h @@ -614,6 +614,8 @@ typedef struct QEMUSnapshotInfo { use a disk image format on top of it (default for bdrv_file_open()) */ +#define BDRV_O_EXTENDABLE 0x0080 /* allow writes out of original size range; + only effective for some drivers */ void bdrv_init(void); BlockDriver *bdrv_find_format(const char *format_name); -- 2.30.2