Before the purgatory is loaded several checks are done whether the ELF file in kexec_purgatory is valid or not. These checks are incomplete. For example they don't check for the total size of the sections defined in the section header table or if the entry point actually points into the purgatory. On the other hand the purgatory, although an ELF file on its own, is part of the kernel. Thus not trusting the purgatory means not trusting the kernel build itself. So remove all validity checks on the purgatory and just trust the kernel build. Signed-off-by: Philipp Rudo <prudo@xxxxxxxxxxxxxxxxxx> --- kernel/kexec_file.c | 14 -------------- 1 file changed, 14 deletions(-) diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index e5bcd94c1efb..0f044457b40c 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -880,22 +880,8 @@ int kexec_load_purgatory(struct kimage *image, unsigned long min, if (kexec_purgatory_size <= 0) return -EINVAL; - if (kexec_purgatory_size < sizeof(Elf_Ehdr)) - return -ENOEXEC; - pi->ehdr = (Elf_Ehdr *)kexec_purgatory; - if (memcmp(pi->ehdr->e_ident, ELFMAG, SELFMAG) != 0 - || pi->ehdr->e_type != ET_REL - || !elf_check_arch(pi->ehdr) - || pi->ehdr->e_shentsize != sizeof(Elf_Shdr)) - return -ENOEXEC; - - if (pi->ehdr->e_shoff >= kexec_purgatory_size - || (pi->ehdr->e_shnum * sizeof(Elf_Shdr) > - kexec_purgatory_size - pi->ehdr->e_shoff)) - return -ENOEXEC; - ret = __kexec_load_purgatory(image, min, max, top_down); if (ret) return ret; -- 2.13.5 _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
