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-rw-r--r--arch/s390/boot/startup.c76
1 files changed, 66 insertions, 10 deletions
diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c
index 9cc76e6317..9e2c9027e9 100644
--- a/arch/s390/boot/startup.c
+++ b/arch/s390/boot/startup.c
@@ -32,7 +32,6 @@ unsigned long __bootdata_preserved(max_mappable);
unsigned long __bootdata(ident_map_size);
u64 __bootdata_preserved(stfle_fac_list[16]);
-u64 __bootdata_preserved(alt_stfle_fac_list[16]);
struct oldmem_data __bootdata_preserved(oldmem_data);
struct machine_info machine;
@@ -141,7 +140,8 @@ 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 +172,54 @@ 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 +347,19 @@ 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 +414,7 @@ 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 +422,7 @@ 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 +447,20 @@ 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();