diff options
Diffstat (limited to 'arch/s390/boot')
| -rw-r--r-- | arch/s390/boot/.gitignore | 1 | ||||
| -rw-r--r-- | arch/s390/boot/Makefile | 25 | ||||
| -rw-r--r-- | arch/s390/boot/boot.h | 6 | ||||
| -rw-r--r-- | arch/s390/boot/startup.c | 75 | ||||
| -rw-r--r-- | arch/s390/boot/vmlinux.lds.S | 48 |
5 files changed, 140 insertions, 15 deletions
diff --git a/arch/s390/boot/.gitignore b/arch/s390/boot/.gitignore index f56591bc0897..f5ef099e2fd3 100644 --- a/arch/s390/boot/.gitignore +++ b/arch/s390/boot/.gitignore @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only image bzImage +relocs.S section_cmp.* vmlinux vmlinux.lds diff --git a/arch/s390/boot/Makefile b/arch/s390/boot/Makefile index c7c81e5f9218..294f08a8811a 100644 --- a/arch/s390/boot/Makefile +++ b/arch/s390/boot/Makefile @@ -37,7 +37,8 @@ CFLAGS_sclp_early_core.o += -I$(srctree)/drivers/s390/char obj-y := head.o als.o startup.o physmem_info.o ipl_parm.o ipl_report.o vmem.o obj-y += string.o ebcdic.o sclp_early_core.o mem.o ipl_vmparm.o cmdline.o -obj-y += version.o pgm_check_info.o ctype.o ipl_data.o machine_kexec_reloc.o +obj-y += version.o pgm_check_info.o ctype.o ipl_data.o +obj-y += $(if $(CONFIG_PIE_BUILD),machine_kexec_reloc.o,relocs.o) obj-$(findstring y, $(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) $(CONFIG_PGSTE)) += uv.o obj-$(CONFIG_RANDOMIZE_BASE) += kaslr.o obj-y += $(if $(CONFIG_KERNEL_UNCOMPRESSED),,decompressor.o) info.o @@ -48,6 +49,9 @@ targets := bzImage section_cmp.boot.data section_cmp.boot.preserved.data $(obj-y targets += vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 targets += vmlinux.bin.xz vmlinux.bin.lzma vmlinux.bin.lzo vmlinux.bin.lz4 targets += vmlinux.bin.zst info.bin syms.bin vmlinux.syms $(obj-all) +ifndef CONFIG_PIE_BUILD +targets += relocs.S +endif OBJECTS := $(addprefix $(obj)/,$(obj-y)) OBJECTS_ALL := $(addprefix $(obj)/,$(obj-all)) @@ -56,9 +60,9 @@ clean-files += vmlinux.map quiet_cmd_section_cmp = SECTCMP $* define cmd_section_cmp - s1=`$(OBJDUMP) -t -j "$*" "$<" | sort | \ + s1=`$(OBJDUMP) -t "$<" | grep "\s$*\s\+" | sort | \ sed -n "/0000000000000000/! s/.*\s$*\s\+//p" | sha256sum`; \ - s2=`$(OBJDUMP) -t -j "$*" "$(word 2,$^)" | sort | \ + s2=`$(OBJDUMP) -t "$(word 2,$^)" | grep "\s$*\s\+" | sort | \ sed -n "/0000000000000000/! s/.*\s$*\s\+//p" | sha256sum`; \ if [ "$$s1" != "$$s2" ]; then \ echo "error: section $* differs between $< and $(word 2,$^)" >&2; \ @@ -73,11 +77,12 @@ $(obj)/bzImage: $(obj)/vmlinux $(obj)/section_cmp.boot.data $(obj)/section_cmp.b $(obj)/section_cmp%: vmlinux $(obj)/vmlinux FORCE $(call if_changed,section_cmp) -LDFLAGS_vmlinux := --oformat $(LD_BFD) -e startup $(if $(CONFIG_VMLINUX_MAP),-Map=$(obj)/vmlinux.map) --build-id=sha1 -T +LDFLAGS_vmlinux-$(CONFIG_LD_ORPHAN_WARN) := --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL) +LDFLAGS_vmlinux := $(LDFLAGS_vmlinux-y) --oformat $(LD_BFD) -e startup $(if $(CONFIG_VMLINUX_MAP),-Map=$(obj)/vmlinux.map) --build-id=sha1 -T $(obj)/vmlinux: $(obj)/vmlinux.lds $(OBJECTS_ALL) FORCE $(call if_changed,ld) -LDFLAGS_vmlinux.syms := --oformat $(LD_BFD) -e startup -T +LDFLAGS_vmlinux.syms := $(LDFLAGS_vmlinux-y) --oformat $(LD_BFD) -e startup -T $(obj)/vmlinux.syms: $(obj)/vmlinux.lds $(OBJECTS) FORCE $(call if_changed,ld) @@ -93,7 +98,7 @@ OBJCOPYFLAGS_syms.o := -I binary -O elf64-s390 -B s390:64-bit --rename-section . $(obj)/syms.o: $(obj)/syms.bin FORCE $(call if_changed,objcopy) -OBJCOPYFLAGS_info.bin := -O binary --only-section=.vmlinux.info --set-section-flags .vmlinux.info=load +OBJCOPYFLAGS_info.bin := -O binary --only-section=.vmlinux.info --set-section-flags .vmlinux.info=alloc,load $(obj)/info.bin: vmlinux FORCE $(call if_changed,objcopy) @@ -105,6 +110,14 @@ OBJCOPYFLAGS_vmlinux.bin := -O binary --remove-section=.comment --remove-section $(obj)/vmlinux.bin: vmlinux FORCE $(call if_changed,objcopy) +ifndef CONFIG_PIE_BUILD +CMD_RELOCS=arch/s390/tools/relocs +quiet_cmd_relocs = RELOCS $@ + cmd_relocs = $(CMD_RELOCS) $< > $@ +$(obj)/relocs.S: vmlinux FORCE + $(call if_changed,relocs) +endif + suffix-$(CONFIG_KERNEL_GZIP) := .gz suffix-$(CONFIG_KERNEL_BZIP2) := .bz2 suffix-$(CONFIG_KERNEL_LZ4) := .lz4 diff --git a/arch/s390/boot/boot.h b/arch/s390/boot/boot.h index 222c6886acf6..567d60f78bbc 100644 --- a/arch/s390/boot/boot.h +++ b/arch/s390/boot/boot.h @@ -25,9 +25,14 @@ struct vmlinux_info { unsigned long bootdata_size; unsigned long bootdata_preserved_off; unsigned long bootdata_preserved_size; +#ifdef CONFIG_PIE_BUILD unsigned long dynsym_start; unsigned long rela_dyn_start; unsigned long rela_dyn_end; +#else + unsigned long got_start; + unsigned long got_end; +#endif unsigned long amode31_size; unsigned long init_mm_off; unsigned long swapper_pg_dir_off; @@ -83,6 +88,7 @@ extern unsigned long vmalloc_size; extern int vmalloc_size_set; extern char __boot_data_start[], __boot_data_end[]; extern char __boot_data_preserved_start[], __boot_data_preserved_end[]; +extern char __vmlinux_relocs_64_start[], __vmlinux_relocs_64_end[]; extern char _decompressor_syms_start[], _decompressor_syms_end[]; extern char _stack_start[], _stack_end[]; extern char _end[], _decompressor_end[]; diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c index 9cc76e631759..6cf89314209a 100644 --- a/arch/s390/boot/startup.c +++ b/arch/s390/boot/startup.c @@ -141,7 +141,8 @@ static void copy_bootdata(void) memcpy((void *)vmlinux.bootdata_preserved_off, __boot_data_preserved_start, vmlinux.bootdata_preserved_size); } -static void handle_relocs(unsigned long offset) +#ifdef CONFIG_PIE_BUILD +static void kaslr_adjust_relocs(unsigned long min_addr, unsigned long max_addr, unsigned long offset) { Elf64_Rela *rela_start, *rela_end, *rela; int r_type, r_sym, rc; @@ -172,6 +173,54 @@ static void handle_relocs(unsigned long offset) } } +static void kaslr_adjust_got(unsigned long offset) {} +static void rescue_relocs(void) {} +static void free_relocs(void) {} +#else +static int *vmlinux_relocs_64_start; +static int *vmlinux_relocs_64_end; + +static void rescue_relocs(void) +{ + unsigned long size = __vmlinux_relocs_64_end - __vmlinux_relocs_64_start; + + vmlinux_relocs_64_start = (void *)physmem_alloc_top_down(RR_RELOC, size, 0); + vmlinux_relocs_64_end = (void *)vmlinux_relocs_64_start + size; + memmove(vmlinux_relocs_64_start, __vmlinux_relocs_64_start, size); +} + +static void free_relocs(void) +{ + physmem_free(RR_RELOC); +} + +static void kaslr_adjust_relocs(unsigned long min_addr, unsigned long max_addr, unsigned long offset) +{ + int *reloc; + long loc; + + /* Adjust R_390_64 relocations */ + for (reloc = vmlinux_relocs_64_start; reloc < vmlinux_relocs_64_end; reloc++) { + loc = (long)*reloc + offset; + if (loc < min_addr || loc > max_addr) + error("64-bit relocation outside of kernel!\n"); + *(u64 *)loc += offset; + } +} + +static void kaslr_adjust_got(unsigned long offset) +{ + u64 *entry; + + /* + * Even without -fPIE, Clang still uses a global offset table for some + * reason. Adjust the GOT entries. + */ + for (entry = (u64 *)vmlinux.got_start; entry < (u64 *)vmlinux.got_end; entry++) + *entry += offset; +} +#endif + /* * Merge information from several sources into a single ident_map_size value. * "ident_map_size" represents the upper limit of physical memory we may ever @@ -299,14 +348,19 @@ static void setup_vmalloc_size(void) vmalloc_size = max(size, vmalloc_size); } -static void offset_vmlinux_info(unsigned long offset) +static void kaslr_adjust_vmlinux_info(unsigned long offset) { *(unsigned long *)(&vmlinux.entry) += offset; vmlinux.bootdata_off += offset; vmlinux.bootdata_preserved_off += offset; +#ifdef CONFIG_PIE_BUILD vmlinux.rela_dyn_start += offset; vmlinux.rela_dyn_end += offset; vmlinux.dynsym_start += offset; +#else + vmlinux.got_start += offset; + vmlinux.got_end += offset; +#endif vmlinux.init_mm_off += offset; vmlinux.swapper_pg_dir_off += offset; vmlinux.invalid_pg_dir_off += offset; @@ -361,6 +415,7 @@ void startup_kernel(void) detect_physmem_online_ranges(max_physmem_end); save_ipl_cert_comp_list(); rescue_initrd(safe_addr, ident_map_size); + rescue_relocs(); if (kaslr_enabled()) { vmlinux_lma = randomize_within_range(vmlinux.image_size + vmlinux.bss_size, @@ -368,7 +423,7 @@ void startup_kernel(void) ident_map_size); if (vmlinux_lma) { __kaslr_offset = vmlinux_lma - vmlinux.default_lma; - offset_vmlinux_info(__kaslr_offset); + kaslr_adjust_vmlinux_info(__kaslr_offset); } } vmlinux_lma = vmlinux_lma ?: vmlinux.default_lma; @@ -393,18 +448,20 @@ void startup_kernel(void) /* * The order of the following operations is important: * - * - handle_relocs() must follow clear_bss_section() to establish static - * memory references to data in .bss to be used by setup_vmem() + * - kaslr_adjust_relocs() must follow clear_bss_section() to establish + * static memory references to data in .bss to be used by setup_vmem() * (i.e init_mm.pgd) * - * - setup_vmem() must follow handle_relocs() to be able using + * - setup_vmem() must follow kaslr_adjust_relocs() to be able using * static memory references to data in .bss (i.e init_mm.pgd) * - * - copy_bootdata() must follow setup_vmem() to propagate changes to - * bootdata made by setup_vmem() + * - copy_bootdata() must follow setup_vmem() to propagate changes + * to bootdata made by setup_vmem() */ clear_bss_section(vmlinux_lma); - handle_relocs(__kaslr_offset); + kaslr_adjust_relocs(vmlinux_lma, vmlinux_lma + vmlinux.image_size, __kaslr_offset); + kaslr_adjust_got(__kaslr_offset); + free_relocs(); setup_vmem(asce_limit); copy_bootdata(); diff --git a/arch/s390/boot/vmlinux.lds.S b/arch/s390/boot/vmlinux.lds.S index 389df0e0d9e5..3d7ea585ab99 100644 --- a/arch/s390/boot/vmlinux.lds.S +++ b/arch/s390/boot/vmlinux.lds.S @@ -31,6 +31,7 @@ SECTIONS _text = .; /* Text */ *(.text) *(.text.*) + INIT_TEXT _etext = . ; } .rodata : { @@ -39,6 +40,9 @@ SECTIONS *(.rodata.*) _erodata = . ; } + .got : { + *(.got) + } NOTES .data : { _data = . ; @@ -106,6 +110,24 @@ SECTIONS _compressed_end = .; } +#ifndef CONFIG_PIE_BUILD + /* + * When the kernel is built with CONFIG_KERNEL_UNCOMPRESSED, the entire + * uncompressed vmlinux.bin is positioned in the bzImage decompressor + * image at the default kernel LMA of 0x100000, enabling it to be + * executed in-place. However, the size of .vmlinux.relocs could be + * large enough to cause an overlap with the uncompressed kernel at the + * address 0x100000. To address this issue, .vmlinux.relocs is + * positioned after the .rodata.compressed. + */ + . = ALIGN(4); + .vmlinux.relocs : { + __vmlinux_relocs_64_start = .; + *(.vmlinux.relocs_64) + __vmlinux_relocs_64_end = .; + } +#endif + #define SB_TRAILER_SIZE 32 /* Trailer needed for Secure Boot */ . += SB_TRAILER_SIZE; /* make sure .sb.trailer does not overwrite the previous section */ @@ -118,8 +140,34 @@ SECTIONS } _end = .; + DWARF_DEBUG + ELF_DETAILS + + /* + * Make sure that the .got.plt is either completely empty or it + * contains only the three reserved double words. + */ + .got.plt : { + *(.got.plt) + } + ASSERT(SIZEOF(.got.plt) == 0 || SIZEOF(.got.plt) == 0x18, "Unexpected GOT/PLT entries detected!") + + /* + * Sections that should stay zero sized, which is safer to + * explicitly check instead of blindly discarding. + */ + .plt : { + *(.plt) *(.plt.*) *(.iplt) *(.igot .igot.plt) + } + ASSERT(SIZEOF(.plt) == 0, "Unexpected run-time procedure linkages detected!") + .rela.dyn : { + *(.rela.*) *(.rela_*) + } + ASSERT(SIZEOF(.rela.dyn) == 0, "Unexpected run-time relocations (.rela) detected!") + /* Sections to be discarded */ /DISCARD/ : { + COMMON_DISCARDS *(.eh_frame) *(__ex_table) *(*__ksymtab*) |