c3bdf263f6
GCC is electing to instrument grub_efi_init() to give it stack smashing protection when configuring with --enable-stack-protector on the x86_64-efi target. In the function prologue, the canary at the top of the stack frame is set to the value of the stack guard. And in the epilogue, the canary is checked to verify if it is equal to the guard and if not to call the stack check fail function. The issue is that grub_efi_init() sets up the guard by initializing it with random bytes, if the firmware supports the RNG protocol. So in its prologue the canary will be set with the value of the uninitialized guard, likely NUL bytes. Then the guard is initialized, and finally the epilogue checks the canary against the guard, which will almost certainly be different. This causes the code path for a smashed stack to be taken, causing the machine to print out a message that stack smashing was detected, wait 5 seconds, and then reboot. Disable grub_efi_init() instrumentation so there is no stack smashing false positive generated. Signed-off-by: Glenn Washburn <development@efficientek.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This is GRUB 2, the second version of the GRand Unified Bootloader. GRUB 2 is rewritten from scratch to make GNU GRUB cleaner, safer, more robust, more powerful, and more portable. See the file NEWS for a description of recent changes to GRUB 2. See the file INSTALL for instructions on how to build and install the GRUB 2 data and program files. See the file MAINTAINERS for information about the GRUB maintainers, etc. If you found a security vulnerability in the GRUB please check the SECURITY file to get more information how to properly report this kind of bugs to the maintainers. Please visit the official web page of GRUB 2, for more information. The URL is <http://www.gnu.org/software/grub/grub.html>. More extensive documentation is available in the Info manual, accessible using 'info grub' after building and installing GRUB 2. There are a number of important user-visible differences from the first version of GRUB, now known as GRUB Legacy. For a summary, please see: info grub Introduction 'Changes from GRUB Legacy'