Message ID | 1345110646-12487-1-git-send-email-kwolf@redhat.com |
---|---|
State | New |
Headers | show |
On Thu, Aug 16, 2012 at 10:50 AM, Kevin Wolf <kwolf@redhat.com> wrote: > The footer takes precedence over the header when it exists. It contains > the real grain directory offset that is missing in the header. Without > this patch, streamOptimized images with a footer cannot be read. > > Signed-off-by: Kevin Wolf <kwolf@redhat.com> > --- > v2: > - Enough footer sanity checks, I hope? :-) > > block/vmdk.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 files changed, 56 insertions(+), 0 deletions(-) Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
On 08/16/2012 05:50 AM, Kevin Wolf wrote: > The footer takes precedence over the header when it exists. It contains > the real grain directory offset that is missing in the header. Without > this patch, streamOptimized images with a footer cannot be read. > > Signed-off-by: Kevin Wolf <kwolf@redhat.com> > --- > v2: > - Enough footer sanity checks, I hope? :-) > > block/vmdk.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 files changed, 56 insertions(+), 0 deletions(-) > > diff --git a/block/vmdk.c b/block/vmdk.c > index 9648398..bba4c61 100644 > --- a/block/vmdk.c > +++ b/block/vmdk.c > @@ -35,6 +35,7 @@ > #define VMDK4_FLAG_RGD (1 << 1) > #define VMDK4_FLAG_COMPRESS (1 << 16) > #define VMDK4_FLAG_MARKER (1 << 17) > +#define VMDK4_GD_AT_END 0xffffffffffffffffULL > > typedef struct { > uint32_t version; > @@ -115,6 +116,13 @@ typedef struct VmdkGrainMarker { > uint8_t data[0]; > } VmdkGrainMarker; > > +enum { > + MARKER_END_OF_STREAM = 0, > + MARKER_GRAIN_TABLE = 1, > + MARKER_GRAIN_DIRECTORY = 2, > + MARKER_FOOTER = 3, > +}; > + > static int vmdk_probe(const uint8_t *buf, int buf_size, const char *filename) > { > uint32_t magic; > @@ -451,6 +459,54 @@ static int vmdk_open_vmdk4(BlockDriverState *bs, > if (header.capacity == 0 && header.desc_offset) { > return vmdk_open_desc_file(bs, flags, header.desc_offset << 9); > } > + > + if (le64_to_cpu(header.gd_offset) == VMDK4_GD_AT_END) { > + /* > + * The footer takes precedence over the header, so read it in. The > + * footer starts at offset -1024 from the end: One sector for the > + * footer, and another one for the end-of-stream marker. > + */ > + struct { > + struct { > + uint64_t val; > + uint32_t size; > + uint32_t type; > + uint8_t pad[512 - 16]; > + } QEMU_PACKED footer_marker; > + > + uint32_t magic; > + VMDK4Header header; > + uint8_t pad[512 - 4 - sizeof(VMDK4Header)]; > + > + struct { > + uint64_t val; > + uint32_t size; > + uint32_t type; > + uint8_t pad[512 - 16]; > + } QEMU_PACKED eos_marker; > + } QEMU_PACKED footer; > + > + ret = bdrv_pread(file, > + bs->file->total_sectors * 512 - 1536, > + &footer, sizeof(footer)); > + if (ret < 0) { > + return ret; > + } > + > + /* Some sanity checks for the footer */ > + if (be32_to_cpu(footer.magic) != VMDK4_MAGIC || > + le32_to_cpu(footer.footer_marker.size) != 0 || > + le32_to_cpu(footer.footer_marker.type) != MARKER_FOOTER || > + le64_to_cpu(footer.eos_marker.val) != 0 || > + le32_to_cpu(footer.eos_marker.size) != 0 || > + le32_to_cpu(footer.eos_marker.type) != MARKER_END_OF_STREAM) > + { > + return -EINVAL; > + } > + > + header = footer.header; > + } > + > l1_entry_sectors = le32_to_cpu(header.num_gtes_per_gte) > * le64_to_cpu(header.granularity); > if (l1_entry_sectors == 0) { > Reviewed-by: Jeff Cody <jcody@redhat.com>
diff --git a/block/vmdk.c b/block/vmdk.c index 9648398..bba4c61 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -35,6 +35,7 @@ #define VMDK4_FLAG_RGD (1 << 1) #define VMDK4_FLAG_COMPRESS (1 << 16) #define VMDK4_FLAG_MARKER (1 << 17) +#define VMDK4_GD_AT_END 0xffffffffffffffffULL typedef struct { uint32_t version; @@ -115,6 +116,13 @@ typedef struct VmdkGrainMarker { uint8_t data[0]; } VmdkGrainMarker; +enum { + MARKER_END_OF_STREAM = 0, + MARKER_GRAIN_TABLE = 1, + MARKER_GRAIN_DIRECTORY = 2, + MARKER_FOOTER = 3, +}; + static int vmdk_probe(const uint8_t *buf, int buf_size, const char *filename) { uint32_t magic; @@ -451,6 +459,54 @@ static int vmdk_open_vmdk4(BlockDriverState *bs, if (header.capacity == 0 && header.desc_offset) { return vmdk_open_desc_file(bs, flags, header.desc_offset << 9); } + + if (le64_to_cpu(header.gd_offset) == VMDK4_GD_AT_END) { + /* + * The footer takes precedence over the header, so read it in. The + * footer starts at offset -1024 from the end: One sector for the + * footer, and another one for the end-of-stream marker. + */ + struct { + struct { + uint64_t val; + uint32_t size; + uint32_t type; + uint8_t pad[512 - 16]; + } QEMU_PACKED footer_marker; + + uint32_t magic; + VMDK4Header header; + uint8_t pad[512 - 4 - sizeof(VMDK4Header)]; + + struct { + uint64_t val; + uint32_t size; + uint32_t type; + uint8_t pad[512 - 16]; + } QEMU_PACKED eos_marker; + } QEMU_PACKED footer; + + ret = bdrv_pread(file, + bs->file->total_sectors * 512 - 1536, + &footer, sizeof(footer)); + if (ret < 0) { + return ret; + } + + /* Some sanity checks for the footer */ + if (be32_to_cpu(footer.magic) != VMDK4_MAGIC || + le32_to_cpu(footer.footer_marker.size) != 0 || + le32_to_cpu(footer.footer_marker.type) != MARKER_FOOTER || + le64_to_cpu(footer.eos_marker.val) != 0 || + le32_to_cpu(footer.eos_marker.size) != 0 || + le32_to_cpu(footer.eos_marker.type) != MARKER_END_OF_STREAM) + { + return -EINVAL; + } + + header = footer.header; + } + l1_entry_sectors = le32_to_cpu(header.num_gtes_per_gte) * le64_to_cpu(header.granularity); if (l1_entry_sectors == 0) {
The footer takes precedence over the header when it exists. It contains the real grain directory offset that is missing in the header. Without this patch, streamOptimized images with a footer cannot be read. Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- v2: - Enough footer sanity checks, I hope? :-) block/vmdk.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 56 insertions(+), 0 deletions(-)