Commit e39e959e fixed an invalid assertion in the .bdrv_length
implementation, but left a similar assertion in place for
.bdrv_truncate. Instead of crashing when the user requests a too large
image size, fail gracefully.

A file size of exactly INT64_MAX caused failure before, but is actually
legal.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block/crypto.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/block/crypto.c b/block/crypto.c
index e0b8856f74..bc6c7e3795 100644
--- a/block/crypto.c
+++ b/block/crypto.c
@@ -357,7 +357,11 @@ static int block_crypto_truncate(BlockDriverState *bs, int64_t offset,
     BlockCrypto *crypto = bs->opaque;
     uint64_t payload_offset =
         qcrypto_block_get_payload_offset(crypto->block);
-    assert(payload_offset < (INT64_MAX - offset));
+
+    if (payload_offset > INT64_MAX - offset) {
+        error_setg(errp, "The requested file size is too large");
+        return -EFBIG;
+    }
 
     offset += payload_offset;
 
-- 
2.13.6

On 03/20/2018 12:36 PM, Kevin Wolf wrote:
> Commit e39e959e fixed an invalid assertion in the .bdrv_length
> implementation, but left a similar assertion in place for
> .bdrv_truncate. Instead of crashing when the user requests a too large
> image size, fail gracefully.
> 
> A file size of exactly INT64_MAX caused failure before, but is actually
> legal.
> 
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
>   block/crypto.c | 6 +++++-
>   1 file changed, 5 insertions(+), 1 deletion(-)

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org

On Tue, Mar 20, 2018 at 06:36:25PM +0100, Kevin Wolf wrote:
> Commit e39e959e fixed an invalid assertion in the .bdrv_length
> implementation, but left a similar assertion in place for
> .bdrv_truncate. Instead of crashing when the user requests a too large
> image size, fail gracefully.
> 
> A file size of exactly INT64_MAX caused failure before, but is actually
> legal.
> 
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
>  block/crypto.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>


Regards,
Daniel
-- 
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