Re: [SECURITY PATCH 108/117] util/mkimage: Refactor section setup to use a helper
Hi Adrian, On Tue, Mar 23, 2021 at 08:16:43PM +0100, John Paul Adrian Glaubitz wrote: > Hello! > > On 3/18/21 9:38 AM, John Paul Adrian Glaubitz wrote: > > On 3/2/21 7:01 PM, Daniel Kiper wrote: > >> From: Peter Jones > >> > >> Add a init_pe_section() helper function to setup PE sections. This makes > >> the code simpler and easier to read. > >> > >> Signed-off-by: Peter Jones > >> Signed-off-by: Javier Martinez Canillas > >> Reviewed-by: Daniel Kiper > > > > This change broke GRUB on ia64 for me. It now fails to perform any basic > > commands: > > Any chance someone could have a look at this? As explained in the follow-up > mails, > the problem is that the pointer pointing to the modules location in the core > image > deviate from the actual modules location as the former was updated but the > former > not. I chatted about that with Javier yesterday. He told me he will take a look at the issue... Daniel
Re: [SECURITY PATCH 108/117] util/mkimage: Refactor section setup to use a helper
Hi Daniel! On 3/23/21 8:35 PM, Daniel Kiper wrote: >> Any chance someone could have a look at this? As explained in the follow-up >> mails, >> the problem is that the pointer pointing to the modules location in the core >> image >> deviate from the actual modules location as the former was updated but the >> former >> not. > > I chatted about that with Javier yesterday. He told me he will take > a look at the issue... Great, thanks. -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer - glaub...@debian.org `. `' Freie Universitaet Berlin - glaub...@physik.fu-berlin.de `-GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
Re: [SECURITY PATCH 108/117] util/mkimage: Refactor section setup to use a helper
Hello! On 3/18/21 9:38 AM, John Paul Adrian Glaubitz wrote: > On 3/2/21 7:01 PM, Daniel Kiper wrote: >> From: Peter Jones >> >> Add a init_pe_section() helper function to setup PE sections. This makes >> the code simpler and easier to read. >> >> Signed-off-by: Peter Jones >> Signed-off-by: Javier Martinez Canillas >> Reviewed-by: Daniel Kiper > > This change broke GRUB on ia64 for me. It now fails to perform any basic > commands: Any chance someone could have a look at this? As explained in the follow-up mails, the problem is that the pointer pointing to the modules location in the core image deviate from the actual modules location as the former was updated but the former not. Adrian -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer - glaub...@debian.org `. `' Freie Universitaet Berlin - glaub...@physik.fu-berlin.de `-GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
Re: [SECURITY PATCH 108/117] util/mkimage: Refactor section setup to use a helper
On 3/20/21 4:05 PM, John Paul Adrian Glaubitz wrote: > However, the modules are still located at the same address in memory which is > why > the module loader can no longer find them. And the new address where the loader is looking for the modules is located at 0x39000 but the modules are still located at 0x384E0. Thus, mkimage should be patched to move the modules to 39000 so that the loader can find them. Adrian -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer - glaub...@debian.org `. `' Freie Universitaet Berlin - glaub...@physik.fu-berlin.de `-GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
Re: [SECURITY PATCH 108/117] util/mkimage: Refactor section setup to use a helper
Hello! On 3/18/21 9:38 AM, John Paul Adrian Glaubitz wrote: > This change broke GRUB on ia64 for me. It now fails to perform any basic > commands: > > Loading.: grub > Starting: grub > Welcome to GRUB! > > > > error: unknown filesystem. > Entering rescue mode... > grub rescue> insmod ext2 > error: unknown filesystem. > grub rescue> help > Unknown command `help'. > grub rescue> ? > Unknown command `?'. > grub rescue> linux > Unknown command `linux'. > grub rescue> The problem seems that the module loader tries to load the modules from the address mentioned in the PE header which has changed before this patch was introduced. However, the modules are still located at the same address in memory which is why the module loader can no longer find them. For reference, here is a hex diff of core.efi for the working and non-working builds (without and with the patch): --- grub-working.txt2021-03-20 15:45:43.788950935 +0100 +++ grub-broken.txt 2021-03-20 15:46:05.55451 +0100 @@ -25,10 +25,10 @@ 0180: 2e74 6578 7400 .text... 0190: 00e0 0100 0010 00e0 0100 0010 01a0: 2000 0060 ..` -01b0: 2e64 6174 6100 e094 0100 00f0 0100 .data... -01c0: e094 0100 00f0 0100 +01b0: 2e64 6174 6100 00a0 0100 00f0 0100 .data... +01c0: 00a0 0100 00f0 0100 01d0: 4000 00c0 6d6f 6473 @...mods -01e0: 206b e084 0300 206b e084 0300 k.. k.. +01e0: 0060 0090 0300 0060 0090 0300 .`...`.. 01f0: 4000 00c0 @... 0200: 2e72 656c 6f63 0010 00f0 0300 .reloc.. 0210: 0010 00f0 0300 Adrian -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer - glaub...@debian.org `. `' Freie Universitaet Berlin - glaub...@physik.fu-berlin.de `-GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
Re: [SECURITY PATCH 108/117] util/mkimage: Refactor section setup to use a helper
Hi! On 3/2/21 7:01 PM, Daniel Kiper wrote: > From: Peter Jones > > Add a init_pe_section() helper function to setup PE sections. This makes > the code simpler and easier to read. > > Signed-off-by: Peter Jones > Signed-off-by: Javier Martinez Canillas > Reviewed-by: Daniel Kiper This change broke GRUB on ia64 for me. It now fails to perform any basic commands: Loading.: grub Starting: grub Welcome to GRUB! error: unknown filesystem. Entering rescue mode... grub rescue> insmod ext2 error: unknown filesystem. grub rescue> help Unknown command `help'. grub rescue> ? Unknown command `?'. grub rescue> linux Unknown command `linux'. grub rescue> Adrian -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer - glaub...@debian.org `. `' Freie Universitaet Berlin - glaub...@physik.fu-berlin.de `-GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
