URL:
<http://savannah.gnu.org/bugs/?38800>
Summary: x86-64: overflowing relocation crashes GRUB
Project: GNU GRUB
Submitted by: qwertial
Submitted on: Mon 22 Apr 2013 05:46:08 AM GMT
Category: None
Severity: Major
Priority: 5 - Normal
Item Group: None
Status: None
Privacy: Public
Assigned to: None
Originator Name:
Originator Email:
Open/Closed: Open
Discussion Lock: Any
Release:
Release: Bazaar - trunk
Reproducibility: Every Time
Planned Release: None
_______________________________________________________
Details:
The x86-64 version of grub_arch_dl_relocate_symbols() does not check whether
an R_X86_64_PC32 relocation fits into 32 bits. This makes grub-emu-lite crash
(with default compiler options) when trying to execute the module, since
module code is loaded above 0x7ffff0000000, while grub-emu-lite code is loaded
around 0x400000.
Possible solutions:
0. Add an overflow check to grub_arch_dl_relocate_symbols().
1. Try to allocate module code near core code.
2. Use the system's dlopen() and dlsym() calls for loading modules in
grub-emu-lite instead of the built-in loader.
3. Compile with -mcmodel=large, which makes 32-bit relocations disappear.
_______________________________________________________
Reply to this item at:
<http://savannah.gnu.org/bugs/?38800>
_______________________________________________
Message sent via/by Savannah
http://savannah.gnu.org/
_______________________________________________
Bug-grub mailing list
[email protected]
https://lists.gnu.org/mailman/listinfo/bug-grub
