diff options
| author | Kevin Wolf <kwolf@redhat.com> | 2014-11-25 18:12:40 +0100 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2014-12-10 10:31:13 +0100 |
| commit | 2ebafc854d109ff09b66fb4dd62c2c53fc29754a (patch) | |
| tree | 2647037960aee19ef9c07457a6e4b3bd93330ffa /block | |
| parent | 3dc7ca3c97dff8732e38828b38e0497efba0fedf (diff) | |
qcow2: Fix header extension size check
After reading the extension header, offset is incremented, but not
checked against end_offset any more. This way an integer overflow could
happen when checking whether the extension end is within the allowed
range, effectively disabling the check.
This patch adds the missing check and a test case for it.
Cc: qemu-stable@nongnu.org
Reported-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1416935562-7760-2-git-send-email-kwolf@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/qcow2.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/block/qcow2.c b/block/qcow2.c index d12049451a..8b9ffc4cc0 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -117,7 +117,7 @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset, #ifdef DEBUG_EXT printf("ext.magic = 0x%x\n", ext.magic); #endif - if (ext.len > end_offset - offset) { + if (offset > end_offset || ext.len > end_offset - offset) { error_setg(errp, "Header extension too large"); return -EINVAL; } |