The dill file has an index at the end. The last 4 bytes of that index is
a size that indicates how big the file is. This is done to support
concatenated dill files. If the dill is invalid and the size is read as 0
both the VM and the dart kernel reader will go into an infinite loop where
it allocates another list entry on every loop iteration (making the whole
loop not infinate because we will run out of ram soon enough).
This CL fixes the issue by checking the size to be possitive.
Change-Id: I42da0557c6d4a274fdbe1a729fdaf5b8f149b187
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/148538
Reviewed-by: Johnni Winther <johnniwinther@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Jens Johansen <jensj@google.com>
Johnni Winther