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-rw-r--r--lib/Kconfig.debug2
-rw-r--r--tools/objtool/arch/x86/decode.c34
-rw-r--r--tools/objtool/check.c151
-rw-r--r--tools/objtool/include/objtool/arch.h2
-rw-r--r--tools/objtool/include/objtool/elf.h1
-rw-r--r--tools/objtool/include/objtool/objtool.h9
-rw-r--r--tools/objtool/objtool.c22
7 files changed, 208 insertions, 13 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index ed4a31e34098..63a4735cef66 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -458,7 +458,7 @@ config STACK_VALIDATION
config VMLINUX_VALIDATION
bool
- depends on STACK_VALIDATION && DEBUG_ENTRY && !PARAVIRT
+ depends on STACK_VALIDATION && DEBUG_ENTRY
default y
config VMLINUX_MAP
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index 340a3dce94a0..3172983bf808 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -20,6 +20,7 @@
#include <objtool/arch.h>
#include <objtool/warn.h>
#include <objtool/endianness.h>
+#include <objtool/builtin.h>
#include <arch/elf.h>
static int is_x86_64(const struct elf *elf)
@@ -102,12 +103,13 @@ unsigned long arch_jump_destination(struct instruction *insn)
#define rm_is_mem(reg) (mod_is_mem() && !is_RIP() && rm_is(reg))
#define rm_is_reg(reg) (mod_is_reg() && modrm_rm == (reg))
-int arch_decode_instruction(const struct elf *elf, const struct section *sec,
+int arch_decode_instruction(struct objtool_file *file, const struct section *sec,
unsigned long offset, unsigned int maxlen,
unsigned int *len, enum insn_type *type,
unsigned long *immediate,
struct list_head *ops_list)
{
+ const struct elf *elf = file->elf;
struct insn insn;
int x86_64, ret;
unsigned char op1, op2,
@@ -544,6 +546,36 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
*type = INSN_RETURN;
break;
+ case 0xc7: /* mov imm, r/m */
+ if (!noinstr)
+ break;
+
+ if (insn.length == 3+4+4 && !strncmp(sec->name, ".init.text", 10)) {
+ struct reloc *immr, *disp;
+ struct symbol *func;
+ int idx;
+
+ immr = find_reloc_by_dest(elf, (void *)sec, offset+3);
+ disp = find_reloc_by_dest(elf, (void *)sec, offset+7);
+
+ if (!immr || strcmp(immr->sym->name, "pv_ops"))
+ break;
+
+ idx = (immr->addend + 8) / sizeof(void *);
+
+ func = disp->sym;
+ if (disp->sym->type == STT_SECTION)
+ func = find_symbol_by_offset(disp->sym->sec, disp->addend);
+ if (!func) {
+ WARN("no func for pv_ops[]");
+ return -1;
+ }
+
+ objtool_pv_add(file, idx, func);
+ }
+
+ break;
+
case 0xcf: /* iret */
/*
* Handle sync_core(), which has an IRET to self.
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index c6f206fee8ff..84e59a97bab6 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -382,7 +382,7 @@ static int decode_instructions(struct objtool_file *file)
insn->sec = sec;
insn->offset = offset;
- ret = arch_decode_instruction(file->elf, sec, offset,
+ ret = arch_decode_instruction(file, sec, offset,
sec->len - offset,
&insn->len, &insn->type,
&insn->immediate,
@@ -420,6 +420,82 @@ err:
return ret;
}
+/*
+ * Read the pv_ops[] .data table to find the static initialized values.
+ */
+static int add_pv_ops(struct objtool_file *file, const char *symname)
+{
+ struct symbol *sym, *func;
+ unsigned long off, end;
+ struct reloc *rel;
+ int idx;
+
+ sym = find_symbol_by_name(file->elf, symname);
+ if (!sym)
+ return 0;
+
+ off = sym->offset;
+ end = off + sym->len;
+ for (;;) {
+ rel = find_reloc_by_dest_range(file->elf, sym->sec, off, end - off);
+ if (!rel)
+ break;
+
+ func = rel->sym;
+ if (func->type == STT_SECTION)
+ func = find_symbol_by_offset(rel->sym->sec, rel->addend);
+
+ idx = (rel->offset - sym->offset) / sizeof(unsigned long);
+
+ objtool_pv_add(file, idx, func);
+
+ off = rel->offset + 1;
+ if (off > end)
+ break;
+ }
+
+ return 0;
+}
+
+/*
+ * Allocate and initialize file->pv_ops[].
+ */
+static int init_pv_ops(struct objtool_file *file)
+{
+ static const char *pv_ops_tables[] = {
+ "pv_ops",
+ "xen_cpu_ops",
+ "xen_irq_ops",
+ "xen_mmu_ops",
+ NULL,
+ };
+ const char *pv_ops;
+ struct symbol *sym;
+ int idx, nr;
+
+ if (!noinstr)
+ return 0;
+
+ file->pv_ops = NULL;
+
+ sym = find_symbol_by_name(file->elf, "pv_ops");
+ if (!sym)
+ return 0;
+
+ nr = sym->len / sizeof(unsigned long);
+ file->pv_ops = calloc(sizeof(struct pv_state), nr);
+ if (!file->pv_ops)
+ return -1;
+
+ for (idx = 0; idx < nr; idx++)
+ INIT_LIST_HEAD(&file->pv_ops[idx].targets);
+
+ for (idx = 0; (pv_ops = pv_ops_tables[idx]); idx++)
+ add_pv_ops(file, pv_ops);
+
+ return 0;
+}
+
static struct instruction *find_last_insn(struct objtool_file *file,
struct section *sec)
{
@@ -893,6 +969,9 @@ static struct reloc *insn_reloc(struct objtool_file *file, struct instruction *i
return NULL;
if (!insn->reloc) {
+ if (!file)
+ return NULL;
+
insn->reloc = find_reloc_by_dest_range(file->elf, insn->sec,
insn->offset, insn->len);
if (!insn->reloc) {
@@ -1882,6 +1961,10 @@ static int decode_sections(struct objtool_file *file)
mark_rodata(file);
+ ret = init_pv_ops(file);
+ if (ret)
+ return ret;
+
ret = decode_instructions(file);
if (ret)
return ret;
@@ -2663,20 +2746,64 @@ static inline bool func_uaccess_safe(struct symbol *func)
static inline const char *call_dest_name(struct instruction *insn)
{
+ static char pvname[16];
+ struct reloc *rel;
+ int idx;
+
if (insn->call_dest)
return insn->call_dest->name;
+ rel = insn_reloc(NULL, insn);
+ if (rel && !strcmp(rel->sym->name, "pv_ops")) {
+ idx = (rel->addend / sizeof(void *));
+ snprintf(pvname, sizeof(pvname), "pv_ops[%d]", idx);
+ return pvname;
+ }
+
return "{dynamic}";
}
-static inline bool noinstr_call_dest(struct symbol *func)
+static bool pv_call_dest(struct objtool_file *file, struct instruction *insn)
+{
+ struct symbol *target;
+ struct reloc *rel;
+ int idx;
+
+ rel = insn_reloc(file, insn);
+ if (!rel || strcmp(rel->sym->name, "pv_ops"))
+ return false;
+
+ idx = (arch_dest_reloc_offset(rel->addend) / sizeof(void *));
+
+ if (file->pv_ops[idx].clean)
+ return true;
+
+ file->pv_ops[idx].clean = true;
+
+ list_for_each_entry(target, &file->pv_ops[idx].targets, pv_target) {
+ if (!target->sec->noinstr) {
+ WARN("pv_ops[%d]: %s", idx, target->name);
+ file->pv_ops[idx].clean = false;
+ }
+ }
+
+ return file->pv_ops[idx].clean;
+}
+
+static inline bool noinstr_call_dest(struct objtool_file *file,
+ struct instruction *insn,
+ struct symbol *func)
{
/*
* We can't deal with indirect function calls at present;
* assume they're instrumented.
*/
- if (!func)
+ if (!func) {
+ if (file->pv_ops)
+ return pv_call_dest(file, insn);
+
return false;
+ }
/*
* If the symbol is from a noinstr section; we good.
@@ -2695,10 +2822,12 @@ static inline bool noinstr_call_dest(struct symbol *func)
return false;
}
-static int validate_call(struct instruction *insn, struct insn_state *state)
+static int validate_call(struct objtool_file *file,
+ struct instruction *insn,
+ struct insn_state *state)
{
if (state->noinstr && state->instr <= 0 &&
- !noinstr_call_dest(insn->call_dest)) {
+ !noinstr_call_dest(file, insn, insn->call_dest)) {
WARN_FUNC("call to %s() leaves .noinstr.text section",
insn->sec, insn->offset, call_dest_name(insn));
return 1;
@@ -2719,7 +2848,9 @@ static int validate_call(struct instruction *insn, struct insn_state *state)
return 0;
}
-static int validate_sibling_call(struct instruction *insn, struct insn_state *state)
+static int validate_sibling_call(struct objtool_file *file,
+ struct instruction *insn,
+ struct insn_state *state)
{
if (has_modified_stack_frame(insn, state)) {
WARN_FUNC("sibling call from callable instruction with modified stack frame",
@@ -2727,7 +2858,7 @@ static int validate_sibling_call(struct instruction *insn, struct insn_state *st
return 1;
}
- return validate_call(insn, state);
+ return validate_call(file, insn, state);
}
static int validate_return(struct symbol *func, struct instruction *insn, struct insn_state *state)
@@ -2880,7 +3011,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
case INSN_CALL:
case INSN_CALL_DYNAMIC:
- ret = validate_call(insn, &state);
+ ret = validate_call(file, insn, &state);
if (ret)
return ret;
@@ -2899,7 +3030,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
case INSN_JUMP_CONDITIONAL:
case INSN_JUMP_UNCONDITIONAL:
if (is_sibling_call(insn)) {
- ret = validate_sibling_call(insn, &state);
+ ret = validate_sibling_call(file, insn, &state);
if (ret)
return ret;
@@ -2921,7 +3052,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
case INSN_JUMP_DYNAMIC:
case INSN_JUMP_DYNAMIC_CONDITIONAL:
if (is_sibling_call(insn)) {
- ret = validate_sibling_call(insn, &state);
+ ret = validate_sibling_call(file, insn, &state);
if (ret)
return ret;
}
diff --git a/tools/objtool/include/objtool/arch.h b/tools/objtool/include/objtool/arch.h
index 6f482ae2d7d8..589ff58426ab 100644
--- a/tools/objtool/include/objtool/arch.h
+++ b/tools/objtool/include/objtool/arch.h
@@ -69,7 +69,7 @@ struct instruction;
void arch_initial_func_cfi_state(struct cfi_init_state *state);
-int arch_decode_instruction(const struct elf *elf, const struct section *sec,
+int arch_decode_instruction(struct objtool_file *file, const struct section *sec,
unsigned long offset, unsigned int maxlen,
unsigned int *len, enum insn_type *type,
unsigned long *immediate,
diff --git a/tools/objtool/include/objtool/elf.h b/tools/objtool/include/objtool/elf.h
index e34395047530..c3857fadee7a 100644
--- a/tools/objtool/include/objtool/elf.h
+++ b/tools/objtool/include/objtool/elf.h
@@ -57,6 +57,7 @@ struct symbol {
struct symbol *pfunc, *cfunc, *alias;
bool uaccess_safe;
bool static_call_tramp;
+ struct list_head pv_target;
};
struct reloc {
diff --git a/tools/objtool/include/objtool/objtool.h b/tools/objtool/include/objtool/objtool.h
index 24fa83634de4..f99fbc6078d5 100644
--- a/tools/objtool/include/objtool/objtool.h
+++ b/tools/objtool/include/objtool/objtool.h
@@ -14,6 +14,11 @@
#define __weak __attribute__((weak))
+struct pv_state {
+ bool clean;
+ struct list_head targets;
+};
+
struct objtool_file {
struct elf *elf;
struct list_head insn_list;
@@ -25,10 +30,14 @@ struct objtool_file {
unsigned long jl_short, jl_long;
unsigned long jl_nop_short, jl_nop_long;
+
+ struct pv_state *pv_ops;
};
struct objtool_file *objtool_open_read(const char *_objname);
+void objtool_pv_add(struct objtool_file *file, int idx, struct symbol *func);
+
int check(struct objtool_file *file);
int orc_dump(const char *objname);
int orc_create(struct objtool_file *file);
diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c
index e21db8bce493..c90c7084e45a 100644
--- a/tools/objtool/objtool.c
+++ b/tools/objtool/objtool.c
@@ -135,6 +135,28 @@ struct objtool_file *objtool_open_read(const char *_objname)
return &file;
}
+void objtool_pv_add(struct objtool_file *f, int idx, struct symbol *func)
+{
+ if (!noinstr)
+ return;
+
+ if (!f->pv_ops) {
+ WARN("paravirt confusion");
+ return;
+ }
+
+ /*
+ * These functions will be patched into native code,
+ * see paravirt_patch().
+ */
+ if (!strcmp(func->name, "_paravirt_nop") ||
+ !strcmp(func->name, "_paravirt_ident_64"))
+ return;
+
+ list_add(&func->pv_target, &f->pv_ops[idx].targets);
+ f->pv_ops[idx].clean = false;
+}
+
static void cmd_usage(void)
{
unsigned int i, longest = 0;
generated by cgit (git 2.34.1) at 2024-06-06 12:58:36 +0000