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-rw-r--r--arch/x86/boot/compressed/kaslr.c4
-rw-r--r--arch/x86/boot/compressed/misc.c3
-rw-r--r--arch/x86/boot/compressed/misc.h2
-rw-r--r--arch/x86/include/asm/cpu_entry_area.h8
-rw-r--r--arch/x86/include/asm/insn-eval.h1
-rw-r--r--arch/x86/include/asm/irq_stack.h37
-rw-r--r--arch/x86/include/asm/page_64_types.h2
-rw-r--r--arch/x86/include/asm/processor.h1
-rw-r--r--arch/x86/include/asm/stacktrace.h10
-rw-r--r--arch/x86/include/asm/traps.h6
-rw-r--r--arch/x86/kernel/dumpstack_64.c6
-rw-r--r--arch/x86/kernel/process.c1
-rw-r--r--arch/x86/kernel/sev.c32
-rw-r--r--arch/x86/kernel/traps.c58
-rw-r--r--arch/x86/lib/insn-eval.c2
-rw-r--r--arch/x86/lib/kaslr.c18
-rw-r--r--arch/x86/mm/cpu_entry_area.c7
-rw-r--r--arch/x86/mm/fault.c20
-rw-r--r--arch/x86/tools/relocs.c103
19 files changed, 214 insertions, 107 deletions
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 67c3208b668a..411b268bc0a2 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -32,10 +32,6 @@
#include <generated/utsrelease.h>
#include <asm/efi.h>
-/* Macros used by the included decompressor code below. */
-#define STATIC
-#include <linux/decompress/mm.h>
-
#define _SETUP
#include <asm/setup.h> /* For COMMAND_LINE_SIZE */
#undef _SETUP
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 743f13ea25c1..a4339cb2d247 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -28,6 +28,9 @@
/* Macros used by the included decompressor code below. */
#define STATIC static
+/* Define an externally visible malloc()/free(). */
+#define MALLOC_VISIBLE
+#include <linux/decompress/mm.h>
/*
* Provide definitions of memzero and memmove as some of the decompressors will
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 49bde196da9b..16ed360b6692 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -46,6 +46,8 @@ extern char _head[], _end[];
/* misc.c */
extern memptr free_mem_ptr;
extern memptr free_mem_end_ptr;
+void *malloc(int size);
+void free(void *where);
extern struct boot_params *boot_params;
void __putstr(const char *s);
void __puthex(unsigned long value);
diff --git a/arch/x86/include/asm/cpu_entry_area.h b/arch/x86/include/asm/cpu_entry_area.h
index 3d52b094850a..dd5ea1bdf04c 100644
--- a/arch/x86/include/asm/cpu_entry_area.h
+++ b/arch/x86/include/asm/cpu_entry_area.h
@@ -10,6 +10,12 @@
#ifdef CONFIG_X86_64
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+#define VC_EXCEPTION_STKSZ EXCEPTION_STKSZ
+#else
+#define VC_EXCEPTION_STKSZ 0
+#endif
+
/* Macro to enforce the same ordering and stack sizes */
#define ESTACKS_MEMBERS(guardsize, optional_stack_size) \
char DF_stack_guard[guardsize]; \
@@ -28,7 +34,7 @@
/* The exception stacks' physical storage. No guard pages required */
struct exception_stacks {
- ESTACKS_MEMBERS(0, 0)
+ ESTACKS_MEMBERS(0, VC_EXCEPTION_STKSZ)
};
/* The effective cpu entry area mapping with guard pages. */
diff --git a/arch/x86/include/asm/insn-eval.h b/arch/x86/include/asm/insn-eval.h
index 91d7182ad2d6..4ec3613551e3 100644
--- a/arch/x86/include/asm/insn-eval.h
+++ b/arch/x86/include/asm/insn-eval.h
@@ -21,6 +21,7 @@ int insn_get_modrm_rm_off(struct insn *insn, struct pt_regs *regs);
int insn_get_modrm_reg_off(struct insn *insn, struct pt_regs *regs);
unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx);
int insn_get_code_seg_params(struct pt_regs *regs);
+int insn_get_effective_ip(struct pt_regs *regs, unsigned long *ip);
int insn_fetch_from_user(struct pt_regs *regs,
unsigned char buf[MAX_INSN_SIZE]);
int insn_fetch_from_user_inatomic(struct pt_regs *regs,
diff --git a/arch/x86/include/asm/irq_stack.h b/arch/x86/include/asm/irq_stack.h
index 7dcc2b0a4f09..ae9d40f6c706 100644
--- a/arch/x86/include/asm/irq_stack.h
+++ b/arch/x86/include/asm/irq_stack.h
@@ -77,11 +77,11 @@
* Function calls can clobber anything except the callee-saved
* registers. Tell the compiler.
*/
-#define call_on_irqstack(func, asm_call, argconstr...) \
+#define call_on_stack(stack, func, asm_call, argconstr...) \
{ \
register void *tos asm("r11"); \
\
- tos = ((void *)__this_cpu_read(hardirq_stack_ptr)); \
+ tos = ((void *)(stack)); \
\
asm_inline volatile( \
"movq %%rsp, (%[tos]) \n" \
@@ -98,6 +98,25 @@
); \
}
+#define ASM_CALL_ARG0 \
+ "call %P[__func] \n"
+
+#define ASM_CALL_ARG1 \
+ "movq %[arg1], %%rdi \n" \
+ ASM_CALL_ARG0
+
+#define ASM_CALL_ARG2 \
+ "movq %[arg2], %%rsi \n" \
+ ASM_CALL_ARG1
+
+#define ASM_CALL_ARG3 \
+ "movq %[arg3], %%rdx \n" \
+ ASM_CALL_ARG2
+
+#define call_on_irqstack(func, asm_call, argconstr...) \
+ call_on_stack(__this_cpu_read(hardirq_stack_ptr), \
+ func, asm_call, argconstr)
+
/* Macros to assert type correctness for run_*_on_irqstack macros */
#define assert_function_type(func, proto) \
static_assert(__builtin_types_compatible_p(typeof(&func), proto))
@@ -147,8 +166,7 @@
*/
#define ASM_CALL_SYSVEC \
"call irq_enter_rcu \n" \
- "movq %[arg1], %%rdi \n" \
- "call %P[__func] \n" \
+ ASM_CALL_ARG1 \
"call irq_exit_rcu \n"
#define SYSVEC_CONSTRAINTS , [arg1] "r" (regs)
@@ -168,12 +186,10 @@
*/
#define ASM_CALL_IRQ \
"call irq_enter_rcu \n" \
- "movq %[arg1], %%rdi \n" \
- "movl %[arg2], %%esi \n" \
- "call %P[__func] \n" \
+ ASM_CALL_ARG2 \
"call irq_exit_rcu \n"
-#define IRQ_CONSTRAINTS , [arg1] "r" (regs), [arg2] "r" (vector)
+#define IRQ_CONSTRAINTS , [arg1] "r" (regs), [arg2] "r" ((unsigned long)vector)
#define run_irq_on_irqstack_cond(func, regs, vector) \
{ \
@@ -186,9 +202,6 @@
}
#ifndef CONFIG_PREEMPT_RT
-#define ASM_CALL_SOFTIRQ \
- "call %P[__func] \n"
-
/*
* Macro to invoke __do_softirq on the irq stack. This is only called from
* task context when bottom halves are about to be reenabled and soft
@@ -198,7 +211,7 @@
#define do_softirq_own_stack() \
{ \
__this_cpu_write(hardirq_stack_inuse, true); \
- call_on_irqstack(__do_softirq, ASM_CALL_SOFTIRQ); \
+ call_on_irqstack(__do_softirq, ASM_CALL_ARG0); \
__this_cpu_write(hardirq_stack_inuse, false); \
}
diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h
index a8d4ad856568..e9e2c3ba5923 100644
--- a/arch/x86/include/asm/page_64_types.h
+++ b/arch/x86/include/asm/page_64_types.h
@@ -15,7 +15,7 @@
#define THREAD_SIZE_ORDER (2 + KASAN_STACK_ORDER)
#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
-#define EXCEPTION_STACK_ORDER (0 + KASAN_STACK_ORDER)
+#define EXCEPTION_STACK_ORDER (1 + KASAN_STACK_ORDER)
#define EXCEPTION_STKSZ (PAGE_SIZE << EXCEPTION_STACK_ORDER)
#define IRQ_STACK_ORDER (2 + KASAN_STACK_ORDER)
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 887380fc9dfe..191878a65c61 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -516,6 +516,7 @@ struct thread_struct {
*/
unsigned long iopl_emul;
+ unsigned int iopl_warn:1;
unsigned int sig_on_uaccess_err:1;
/*
diff --git a/arch/x86/include/asm/stacktrace.h b/arch/x86/include/asm/stacktrace.h
index f248eb2ac2d4..3881b5333eb8 100644
--- a/arch/x86/include/asm/stacktrace.h
+++ b/arch/x86/include/asm/stacktrace.h
@@ -38,6 +38,16 @@ int get_stack_info(unsigned long *stack, struct task_struct *task,
bool get_stack_info_noinstr(unsigned long *stack, struct task_struct *task,
struct stack_info *info);
+static __always_inline
+bool get_stack_guard_info(unsigned long *stack, struct stack_info *info)
+{
+ /* make sure it's not in the stack proper */
+ if (get_stack_info_noinstr(stack, current, info))
+ return false;
+ /* but if it is in the page below it, we hit a guard */
+ return get_stack_info_noinstr((void *)stack + PAGE_SIZE, current, info);
+}
+
const char *stack_type_name(enum stack_type type);
static inline bool on_stack(struct stack_info *info, void *addr, size_t len)
diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h
index 7f7200021bd1..6221be7cafc3 100644
--- a/arch/x86/include/asm/traps.h
+++ b/arch/x86/include/asm/traps.h
@@ -40,9 +40,9 @@ void math_emulate(struct math_emu_info *);
bool fault_in_kernel_space(unsigned long address);
#ifdef CONFIG_VMAP_STACK
-void __noreturn handle_stack_overflow(const char *message,
- struct pt_regs *regs,
- unsigned long fault_address);
+void __noreturn handle_stack_overflow(struct pt_regs *regs,
+ unsigned long fault_address,
+ struct stack_info *info);
#endif
#endif /* _ASM_X86_TRAPS_H */
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index 5601b95944fa..6c5defd6569a 100644
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -32,9 +32,15 @@ const char *stack_type_name(enum stack_type type)
{
BUILD_BUG_ON(N_EXCEPTION_STACKS != 6);
+ if (type == STACK_TYPE_TASK)
+ return "TASK";
+
if (type == STACK_TYPE_IRQ)
return "IRQ";
+ if (type == STACK_TYPE_SOFTIRQ)
+ return "SOFTIRQ";
+
if (type == STACK_TYPE_ENTRY) {
/*
* On 64-bit, we have a generic entry stack that we
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index eb470be0e5ae..e9ee8b526319 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -146,6 +146,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
frame->ret_addr = (unsigned long) ret_from_fork;
p->thread.sp = (unsigned long) fork_frame;
p->thread.io_bitmap = NULL;
+ p->thread.iopl_warn = 0;
memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
#ifdef CONFIG_X86_64
diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c
index c195ffe58049..74f0ec955384 100644
--- a/arch/x86/kernel/sev.c
+++ b/arch/x86/kernel/sev.c
@@ -46,16 +46,6 @@ static struct ghcb __initdata *boot_ghcb;
struct sev_es_runtime_data {
struct ghcb ghcb_page;
- /* Physical storage for the per-CPU IST stack of the #VC handler */
- char ist_stack[EXCEPTION_STKSZ] __aligned(PAGE_SIZE);
-
- /*
- * Physical storage for the per-CPU fall-back stack of the #VC handler.
- * The fall-back stack is used when it is not safe to switch back to the
- * interrupted stack in the #VC entry code.
- */
- char fallback_stack[EXCEPTION_STKSZ] __aligned(PAGE_SIZE);
-
/*
* Reserve one page per CPU as backup storage for the unencrypted GHCB.
* It is needed when an NMI happens while the #VC handler uses the real
@@ -99,27 +89,6 @@ DEFINE_STATIC_KEY_FALSE(sev_es_enable_key);
/* Needed in vc_early_forward_exception */
void do_early_exception(struct pt_regs *regs, int trapnr);
-static void __init setup_vc_stacks(int cpu)
-{
- struct sev_es_runtime_data *data;
- struct cpu_entry_area *cea;
- unsigned long vaddr;
- phys_addr_t pa;
-
- data = per_cpu(runtime_data, cpu);
- cea = get_cpu_entry_area(cpu);
-
- /* Map #VC IST stack */
- vaddr = CEA_ESTACK_BOT(&cea->estacks, VC);
- pa = __pa(data->ist_stack);
- cea_set_pte((void *)vaddr, pa, PAGE_KERNEL);
-
- /* Map VC fall-back stack */
- vaddr = CEA_ESTACK_BOT(&cea->estacks, VC2);
- pa = __pa(data->fallback_stack);
- cea_set_pte((void *)vaddr, pa, PAGE_KERNEL);
-}
-
static __always_inline bool on_vc_stack(struct pt_regs *regs)
{
unsigned long sp = regs->sp;
@@ -788,7 +757,6 @@ void __init sev_es_init_vc_handling(void)
for_each_possible_cpu(cpu) {
alloc_runtime_data(cpu);
init_ghcb(cpu);
- setup_vc_stacks(cpu);
}
sev_es_setup_play_dead();
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 43f70bc01762..c9d566dcf89a 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -313,17 +313,19 @@ out:
}
#ifdef CONFIG_VMAP_STACK
-__visible void __noreturn handle_stack_overflow(const char *message,
- struct pt_regs *regs,
- unsigned long fault_address)
+__visible void __noreturn handle_stack_overflow(struct pt_regs *regs,
+ unsigned long fault_address,
+ struct stack_info *info)
{
- printk(KERN_EMERG "BUG: stack guard page was hit at %p (stack is %p..%p)\n",
- (void *)fault_address, current->stack,
- (char *)current->stack + THREAD_SIZE - 1);
- die(message, regs, 0);
+ const char *name = stack_type_name(info->type);
+
+ printk(KERN_EMERG "BUG: %s stack guard page was hit at %p (stack is %p..%p)\n",
+ name, (void *)fault_address, info->begin, info->end);
+
+ die("stack guard page", regs, 0);
/* Be absolutely certain we don't return. */
- panic("%s", message);
+ panic("%s stack guard hit", name);
}
#endif
@@ -353,6 +355,7 @@ DEFINE_IDTENTRY_DF(exc_double_fault)
#ifdef CONFIG_VMAP_STACK
unsigned long address = read_cr2();
+ struct stack_info info;
#endif
#ifdef CONFIG_X86_ESPFIX64
@@ -455,10 +458,8 @@ DEFINE_IDTENTRY_DF(exc_double_fault)
* stack even if the actual trigger for the double fault was
* something else.
*/
- if ((unsigned long)task_stack_page(tsk) - 1 - address < PAGE_SIZE) {
- handle_stack_overflow("kernel stack overflow (double-fault)",
- regs, address);
- }
+ if (get_stack_guard_info((void *)address, &info))
+ handle_stack_overflow(regs, address, &info);
#endif
pr_emerg("PANIC: double fault, error_code: 0x%lx\n", error_code);
@@ -528,6 +529,36 @@ static enum kernel_gp_hint get_kernel_gp_address(struct pt_regs *regs,
#define GPFSTR "general protection fault"
+static bool fixup_iopl_exception(struct pt_regs *regs)
+{
+ struct thread_struct *t = &current->thread;
+ unsigned char byte;
+ unsigned long ip;
+
+ if (!IS_ENABLED(CONFIG_X86_IOPL_IOPERM) || t->iopl_emul != 3)
+ return false;
+
+ if (insn_get_effective_ip(regs, &ip))
+ return false;
+
+ if (get_user(byte, (const char __user *)ip))
+ return false;
+
+ if (byte != 0xfa && byte != 0xfb)
+ return false;
+
+ if (!t->iopl_warn && printk_ratelimit()) {
+ pr_err("%s[%d] attempts to use CLI/STI, pretending it's a NOP, ip:%lx",
+ current->comm, task_pid_nr(current), ip);
+ print_vma_addr(KERN_CONT " in ", ip);
+ pr_cont("\n");
+ t->iopl_warn = 1;
+ }
+
+ regs->ip += 1;
+ return true;
+}
+
DEFINE_IDTENTRY_ERRORCODE(exc_general_protection)
{
char desc[sizeof(GPFSTR) + 50 + 2*sizeof(unsigned long) + 1] = GPFSTR;
@@ -553,6 +584,9 @@ DEFINE_IDTENTRY_ERRORCODE(exc_general_protection)
tsk = current;
if (user_mode(regs)) {
+ if (fixup_iopl_exception(regs))
+ goto exit;
+
tsk->thread.error_code = error_code;
tsk->thread.trap_nr = X86_TRAP_GP;
diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c
index a1d24fdc07cf..eb3ccffb9b9d 100644
--- a/arch/x86/lib/insn-eval.c
+++ b/arch/x86/lib/insn-eval.c
@@ -1417,7 +1417,7 @@ void __user *insn_get_addr_ref(struct insn *insn, struct pt_regs *regs)
}
}
-static int insn_get_effective_ip(struct pt_regs *regs, unsigned long *ip)
+int insn_get_effective_ip(struct pt_regs *regs, unsigned long *ip)
{
unsigned long seg_base = 0;
diff --git a/arch/x86/lib/kaslr.c b/arch/x86/lib/kaslr.c
index a53665116458..2b3eb8c948a3 100644
--- a/arch/x86/lib/kaslr.c
+++ b/arch/x86/lib/kaslr.c
@@ -56,11 +56,14 @@ unsigned long kaslr_get_random_long(const char *purpose)
unsigned long raw, random = get_boot_seed();
bool use_i8254 = true;
- debug_putstr(purpose);
- debug_putstr(" KASLR using");
+ if (purpose) {
+ debug_putstr(purpose);
+ debug_putstr(" KASLR using");
+ }
if (has_cpuflag(X86_FEATURE_RDRAND)) {
- debug_putstr(" RDRAND");
+ if (purpose)
+ debug_putstr(" RDRAND");
if (rdrand_long(&raw)) {
random ^= raw;
use_i8254 = false;
@@ -68,7 +71,8 @@ unsigned long kaslr_get_random_long(const char *purpose)
}
if (has_cpuflag(X86_FEATURE_TSC)) {
- debug_putstr(" RDTSC");
+ if (purpose)
+ debug_putstr(" RDTSC");
raw = rdtsc();
random ^= raw;
@@ -76,7 +80,8 @@ unsigned long kaslr_get_random_long(const char *purpose)
}
if (use_i8254) {
- debug_putstr(" i8254");
+ if (purpose)
+ debug_putstr(" i8254");
random ^= i8254();
}
@@ -86,7 +91,8 @@ unsigned long kaslr_get_random_long(const char *purpose)
: "a" (random), "rm" (mix_const));
random += raw;
- debug_putstr("...\n");
+ if (purpose)
+ debug_putstr("...\n");
return random;
}
diff --git a/arch/x86/mm/cpu_entry_area.c b/arch/x86/mm/cpu_entry_area.c
index f5e1e60c9095..6c2f1b76a0b6 100644
--- a/arch/x86/mm/cpu_entry_area.c
+++ b/arch/x86/mm/cpu_entry_area.c
@@ -110,6 +110,13 @@ static void __init percpu_setup_exception_stacks(unsigned int cpu)
cea_map_stack(NMI);
cea_map_stack(DB);
cea_map_stack(MCE);
+
+ if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) {
+ if (cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT)) {
+ cea_map_stack(VC);
+ cea_map_stack(VC2);
+ }
+ }
}
#else
static inline void percpu_setup_exception_stacks(unsigned int cpu)
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 84a2c8c4af73..4bfed53e210e 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -32,6 +32,7 @@
#include <asm/pgtable_areas.h> /* VMALLOC_START, ... */
#include <asm/kvm_para.h> /* kvm_handle_async_pf */
#include <asm/vdso.h> /* fixup_vdso_exception() */
+#include <asm/irq_stack.h>
#define CREATE_TRACE_POINTS
#include <asm/trace/exceptions.h>
@@ -631,6 +632,9 @@ static noinline void
page_fault_oops(struct pt_regs *regs, unsigned long error_code,
unsigned long address)
{
+#ifdef CONFIG_VMAP_STACK
+ struct stack_info info;
+#endif
unsigned long flags;
int sig;
@@ -649,9 +653,7 @@ page_fault_oops(struct pt_regs *regs, unsigned long error_code,
* that we're in vmalloc space to avoid this.
*/
if (is_vmalloc_addr((void *)address) &&
- (((unsigned long)current->stack - 1 - address < PAGE_SIZE) ||
- address - ((unsigned long)current->stack + THREAD_SIZE) < PAGE_SIZE)) {
- unsigned long stack = __this_cpu_ist_top_va(DF) - sizeof(void *);
+ get_stack_guard_info((void *)address, &info)) {
/*
* We're likely to be running with very little stack space
* left. It's plausible that we'd hit this condition but
@@ -662,13 +664,11 @@ page_fault_oops(struct pt_regs *regs, unsigned long error_code,
* and then double-fault, though, because we're likely to
* break the console driver and lose most of the stack dump.
*/
- asm volatile ("movq %[stack], %%rsp\n\t"
- "call handle_stack_overflow\n\t"
- "1: jmp 1b"
- : ASM_CALL_CONSTRAINT
- : "D" ("kernel stack overflow (page fault)"),
- "S" (regs), "d" (address),
- [stack] "rm" (stack));
+ call_on_stack(__this_cpu_ist_top_va(DF) - sizeof(void*),
+ handle_stack_overflow,
+ ASM_CALL_ARG3,
+ , [arg1] "r" (regs), [arg2] "r" (address), [arg3] "r" (&info));
+
unreachable();
}
#endif
diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
index 27c82207d387..3f5d39768287 100644
--- a/arch/x86/tools/relocs.c
+++ b/arch/x86/tools/relocs.c
@@ -14,6 +14,10 @@
static Elf_Ehdr ehdr;
static unsigned long shnum;
static unsigned int shstrndx;
+static unsigned int shsymtabndx;
+static unsigned int shxsymtabndx;
+
+static int sym_index(Elf_Sym *sym);
struct relocs {
uint32_t *offset;
@@ -35,6 +39,7 @@ struct section {
Elf_Shdr shdr;
struct section *link;
Elf_Sym *symtab;
+ Elf32_Word *xsymtab;
Elf_Rel *reltab;
char *strtab;
};
@@ -268,7 +273,7 @@ static const char *sym_name(const char *sym_strtab, Elf_Sym *sym)
name = sym_strtab + sym->st_name;
}
else {
- name = sec_name(sym->st_shndx);
+ name = sec_name(sym_index(sym));
}
return name;
}
@@ -338,6 +343,23 @@ static uint64_t elf64_to_cpu(uint64_t val)
#define elf_xword_to_cpu(x) elf32_to_cpu(x)
#endif
+static int sym_index(Elf_Sym *sym)
+{
+ Elf_Sym *symtab = secs[shsymtabndx].symtab;
+ Elf32_Word *xsymtab = secs[shxsymtabndx].xsymtab;
+ unsigned long offset;
+ int index;
+
+ if (sym->st_shndx != SHN_XINDEX)
+ return sym->st_shndx;
+
+ /* calculate offset of sym from head of table. */
+ offset = (unsigned long)sym - (unsigned long)symtab;
+ index = offset / sizeof(*sym);
+
+ return elf32_to_cpu(xsymtab[index]);
+}
+
static void read_ehdr(FILE *fp)
{
if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1) {
@@ -471,31 +493,60 @@ static void read_strtabs(FILE *fp)
static void read_symtabs(FILE *fp)
{
int i,j;
+
for (i = 0; i < shnum; i++) {
struct section *sec = &secs[i];
- if (sec->shdr.sh_type != SHT_SYMTAB) {
+ int num_syms;
+
+ switch (sec->shdr.sh_type) {
+ case SHT_SYMTAB_SHNDX:
+ sec->xsymtab = malloc(sec->shdr.sh_size);
+ if (!sec->xsymtab) {
+ die("malloc of %" FMT " bytes for xsymtab failed\n",
+ sec->shdr.sh_size);
+ }
+ if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
+ die("Seek to %" FMT " failed: %s\n",
+ sec->shdr.sh_offset, strerror(errno));
+ }
+ if (fread(sec->xsymtab, 1, sec->shdr.sh_size, fp)
+ != sec->shdr.sh_size) {
+ die("Cannot read extended symbol table: %s\n",
+ strerror(errno));
+ }
+ shxsymtabndx = i;
+ continue;
+
+ case SHT_SYMTAB:
+ num_syms = sec->shdr.sh_size / sizeof(Elf_Sym);
+
+ sec->symtab = malloc(sec->shdr.sh_size);
+ if (!sec->symtab) {
+ die("malloc of %" FMT " bytes for symtab failed\n",
+ sec->shdr.sh_size);
+ }
+ if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
+ die("Seek to %" FMT " failed: %s\n",
+ sec->shdr.sh_offset, strerror(errno));
+ }
+ if (fread(sec->symtab, 1, sec->shdr.sh_size, fp)
+ != sec->shdr.sh_size) {
+ die("Cannot read symbol table: %s\n",
+ strerror(errno));
+ }
+ for (j = 0; j < num_syms; j++) {
+ Elf_Sym *sym = &sec->symtab[j];
+
+ sym->st_name = elf_word_to_cpu(sym->st_name);
+ sym->st_value = elf_addr_to_cpu(sym->st_value);
+ sym->st_size = elf_xword_to_cpu(sym->st_size);
+ sym->st_shndx = elf_half_to_cpu(sym->st_shndx);
+ }
+ shsymtabndx = i;
+ continue;
+
+ default:
continue;
- }
- sec->symtab = malloc(sec->shdr.sh_size);
- if (!sec->symtab) {
- die("malloc of %" FMT " bytes for symtab failed\n",
- sec->shdr.sh_size);
- }
- if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
- die("Seek to %" FMT " failed: %s\n",
- sec->shdr.sh_offset, strerror(errno));
- }
- if (fread(sec->symtab, 1, sec->shdr.sh_size, fp)
- != sec->shdr.sh_size) {
- die("Cannot read symbol table: %s\n",
- strerror(errno));
- }
- for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Sym); j++) {
- Elf_Sym *sym = &sec->symtab[j];
- sym->st_name = elf_word_to_cpu(sym->st_name);
- sym->st_value = elf_addr_to_cpu(sym->st_value);
- sym->st_size = elf_xword_to_cpu(sym->st_size);
- sym->st_shndx = elf_half_to_cpu(sym->st_shndx);
}
}
}
@@ -762,7 +813,9 @@ static void percpu_init(void)
*/
static int is_percpu_sym(ElfW(Sym) *sym, const char *symname)
{
- return (sym->st_shndx == per_cpu_shndx) &&
+ int shndx = sym_index(sym);
+
+ return (shndx == per_cpu_shndx) &&
strcmp(symname, "__init_begin") &&
strcmp(symname, "__per_cpu_load") &&
strncmp(symname, "init_per_cpu_", 13);
@@ -1095,7 +1148,7 @@ static int do_reloc_info(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym,
sec_name(sec->shdr.sh_info),
rel_type(ELF_R_TYPE(rel->r_info)),
symname,
- sec_name(sym->st_shndx));
+ sec_name(sym_index(sym)));
return 0;
}
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