ddb6c1bafb
In bsdXX.c and multiboot_elfxx.c, e_phnum is used to obtain the number of program header table entries, but it wasn't being checked if the value was there. According to the elf(5) manual page, "If the number of entries in the program header table is larger than or equal to PN_XNUM (0xffff), this member holds PN_XNUM (0xffff) and the real number of entries in the program header table is held in the sh_info member of the initial entry in section header table. Otherwise, the sh_info member of the initial entry contains the value zero." Since this check wasn't being made, grub_elfXX_get_phnum() is being added to elfXX.c to make this check and use e_phnum if it doesn't have PN_XNUM as a value, else use sh_info. We also need to make sure e_phnum isn't greater than PN_XNUM and sh_info isn't less than PN_XNUM. Note that even though elf.c and elfXX.c are located in grub-core/kern, they are compiled as modules and don't need the EXPORT_FUNC() macro to define the functions in elf.h. Also, changed casts of phnum to match variables being set as well as dropped casts when unnecessary. Signed-off-by: Alec Brown <alec.r.brown@oracle.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.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'