** Description changed: - GRUB version 2.02~beta2-9ubuntu1.2 + [Impact] + If the progress module is loaded, GRUB will crash when loading files over the network. A common scenario where this occurs is when building a GRUB image for EFI netbooting w/ all modules included. MAAS does this when generating it's grubnet EFI binary. MAAS currently works around this by explicitly blacklisting the progress module - but only on arm64 (we'd only observed this on arm64 at the time, and didn't yet know the root cause). - Booting a grub image w/ the progress module on a certain arm64/EFI - systems causes GRUB to crash w/ Synchronous Exceptions. This isn't - reproducible in QEMU. + While the easy workaround is to just omit the progress module, it isn't + at all obvious from the crash that progress.mod is the cause. - Reproduction. The simple case is to create a grub image with *just* the - progress module: + [Test Case] + The simple case is to create a grub image with *just* the progress module and netboot it. For arm64: $ grub-mkimage -v -o grubaa64.efi -O arm64-efi -d /home/dannf/x/usr/lib/grub/arm64-efi progress Booting the resulting image: [1] PXE [2] ubuntu [3] Shell [4] Boot Manager Start: 1 .. Synchronous Exception at 0x0000000FF7C3DDC8 Synchronous Exception at 0x0000000FF7C3DDC8 Synchronous Exception at 0x0000000FF7C3DDC8 Synchronous Exception at 0x0000000FF7C3DDC8 [...] + + [Regression Risk] + The upstream fix for this is a pretty surgical fix to check for NULL before dereferencing a pointer.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1459872 Title: using progress mod w/ net files crashes To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1459872/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
