diff options
author | Serge E. Hallyn <serge@hallyn.com> | 2011-07-25 18:34:35 +0000 |
---|---|---|
committer | Kevin Wolf <kwolf@redhat.com> | 2011-08-01 12:10:28 +0200 |
commit | efc8243d00ab4cf4fa05a9be93233cb883b7caa0 (patch) | |
tree | 1bc4e76fbcba8e3ae7dac008d79e0f1c13e0fd98 | |
parent | 49aa46bb4b894ff8bdb0339ee2a5dd3fcfe93ecd (diff) |
block/vpc.c: Detect too-large vpc file
VHD files technically can be up to 2Tb, but virtual pc is limited
to 127G. Currently qemu-img refused to create vpc files > 127G,
but it is failing to return error when converting from a non-vpc
VHD file which is >127G. It returns success, but creates a truncated
converted image. Also, qemu-img info claims the vpc file is 127G
(and clean).
This patch detects a too-large vpc file and returns -EFBIG. Without
this patch,
=============================================================
root@ip-10-38-123-242:~/qemu-fixed# qemu-img info /mnt/140g-dynamic.vhd
image: /mnt/140g-dynamic.vhd
file format: vpc
virtual size: 127G (136899993600 bytes)
disk size: 284K
root@ip-10-38-123-242:~/qemu-fixed# qemu-img convert -f vpc -O raw /mnt/140g-dynamic.vhd /mnt/y
root@ip-10-38-123-242:~/qemu-fixed# echo $?
0
root@ip-10-38-123-242:~/qemu-fixed# qemu-img info /mnt/y
image: /mnt/y
file format: raw
virtual size: 127G (136899993600 bytes)
disk size: 0
=============================================================
(The 140G image was truncated with no warning or error.)
With the patch, I get:
=============================================================
root@ip-10-38-123-242:~/qemu-fixed# ./qemu-img info /mnt/140g-dynamic.vhd
qemu-img: Could not open '/mnt/140g-dynamic.vhd': File too large
root@ip-10-38-123-242:~/qemu-fixed# ./qemu-img convert -f vpc -O raw /mnt/140g-dynamic.vhd /mnt/y
qemu-img: Could not open '/mnt/140g-dynamic.vhd': File too large
qemu-img: Could not open '/mnt/140g-dynamic.vhd'
=============================================================
See https://bugs.launchpad.net/qemu/+bug/814222 for details.
Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
-rw-r--r-- | block/vpc.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/block/vpc.c b/block/vpc.c index 56865da5bc..fdd5236892 100644 --- a/block/vpc.c +++ b/block/vpc.c @@ -156,6 +156,7 @@ static int vpc_open(BlockDriverState *bs, int flags) struct vhd_dyndisk_header* dyndisk_header; uint8_t buf[HEADER_SIZE]; uint32_t checksum; + int err = -1; if (bdrv_pread(bs->file, 0, s->footer_buf, HEADER_SIZE) != HEADER_SIZE) goto fail; @@ -176,6 +177,11 @@ static int vpc_open(BlockDriverState *bs, int flags) bs->total_sectors = (int64_t) be16_to_cpu(footer->cyls) * footer->heads * footer->secs_per_cyl; + if (bs->total_sectors >= 65535 * 16 * 255) { + err = -EFBIG; + goto fail; + } + if (bdrv_pread(bs->file, be64_to_cpu(footer->data_offset), buf, HEADER_SIZE) != HEADER_SIZE) goto fail; @@ -222,7 +228,7 @@ static int vpc_open(BlockDriverState *bs, int flags) return 0; fail: - return -1; + return err; } /* |