Commit 2a8fcd11 authored by Jack Schwartz's avatar Jack Schwartz Committed by Kevin Wolf
Browse files

multiboot: bss_end_addr can be zero 

The multiboot spec (https://www.gnu.org/software/grub/manual/multiboot/

),
section 3.1.3, allows for bss_end_addr to be zero.

A zero bss_end_addr signifies there is no .bss section.

Suggested-by: default avatarDaniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: default avatarJack Schwartz <jack.schwartz@oracle.com>
Reviewed-by: default avatarDaniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: default avatarPrasad J Pandit <pjp@fedoraproject.org>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent f32408f3

hw/i386/multiboot.c

+10 −8
Original line number Diff line number Diff line
@@ -233,12 +233,6 @@ int load_multiboot(FWCfgState *fw_cfg, 
        mh_entry_addr = ldl_p(header+i+28);



        if (mh_load_end_addr) {

            if (mh_bss_end_addr < mh_load_addr) {

                fprintf(stderr, "invalid mh_bss_end_addr address\n");

                exit(1);

            }

            mb_kernel_size = mh_bss_end_addr - mh_load_addr;



            if (mh_load_end_addr < mh_load_addr) {

                fprintf(stderr, "invalid mh_load_end_addr address\n");

                exit(1);
@@ -249,8 +243,16 @@ int load_multiboot(FWCfgState *fw_cfg, 
                fprintf(stderr, "invalid kernel_file_size\n");

                exit(1);

            }

            mb_kernel_size = kernel_file_size - mb_kernel_text_offset;

            mb_load_size = mb_kernel_size;

            mb_load_size = kernel_file_size - mb_kernel_text_offset;

        }

        if (mh_bss_end_addr) {

            if (mh_bss_end_addr < (mh_load_addr + mb_load_size)) {

                fprintf(stderr, "invalid mh_bss_end_addr address\n");

                exit(1);

            }

            mb_kernel_size = mh_bss_end_addr - mh_load_addr;

        } else {

            mb_kernel_size = mb_load_size;

        }



        /* Valid if mh_flags sets MULTIBOOT_HEADER_HAS_VBE.