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-rw-r--r--tools/objtool/check.c565
1 files changed, 317 insertions, 248 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 6de5085e3e5a..190b2f6e360a 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -5,6 +5,7 @@
#include <string.h>
#include <stdlib.h>
+#include <inttypes.h>
#include <sys/mman.h>
#include <arch/elf.h>
@@ -184,6 +185,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
"do_group_exit",
"stop_this_cpu",
"__invalid_creds",
+ "cpu_startup_entry",
};
if (!func)
@@ -262,7 +264,8 @@ static void init_cfi_state(struct cfi_state *cfi)
cfi->drap_offset = -1;
}
-static void init_insn_state(struct insn_state *state, struct section *sec)
+static void init_insn_state(struct objtool_file *file, struct insn_state *state,
+ struct section *sec)
{
memset(state, 0, sizeof(*state));
init_cfi_state(&state->cfi);
@@ -272,7 +275,7 @@ static void init_insn_state(struct insn_state *state, struct section *sec)
* not correctly determine insn->call_dest->sec (external symbols do
* not have a section).
*/
- if (vmlinux && noinstr && sec)
+ if (opts.link && opts.noinstr && sec)
state->noinstr = sec->noinstr;
}
@@ -338,7 +341,7 @@ static void *cfi_hash_alloc(unsigned long size)
if (cfi_hash == (void *)-1L) {
WARN("mmap fail cfi_hash");
cfi_hash = NULL;
- } else if (stats) {
+ } else if (opts.stats) {
printf("cfi_bits: %d\n", cfi_bits);
}
@@ -433,7 +436,7 @@ static int decode_instructions(struct objtool_file *file)
}
}
- if (stats)
+ if (opts.stats)
printf("nr_insns: %lu\n", nr_insns);
return 0;
@@ -496,7 +499,7 @@ static int init_pv_ops(struct objtool_file *file)
struct symbol *sym;
int idx, nr;
- if (!noinstr)
+ if (!opts.noinstr)
return 0;
file->pv_ops = NULL;
@@ -559,12 +562,12 @@ static int add_dead_ends(struct objtool_file *file)
else if (reloc->addend == reloc->sym->sec->sh.sh_size) {
insn = find_last_insn(file, reloc->sym->sec);
if (!insn) {
- WARN("can't find unreachable insn at %s+0x%x",
+ WARN("can't find unreachable insn at %s+0x%" PRIx64,
reloc->sym->sec->name, reloc->addend);
return -1;
}
} else {
- WARN("can't find unreachable insn at %s+0x%x",
+ WARN("can't find unreachable insn at %s+0x%" PRIx64,
reloc->sym->sec->name, reloc->addend);
return -1;
}
@@ -594,12 +597,12 @@ reachable:
else if (reloc->addend == reloc->sym->sec->sh.sh_size) {
insn = find_last_insn(file, reloc->sym->sec);
if (!insn) {
- WARN("can't find reachable insn at %s+0x%x",
+ WARN("can't find reachable insn at %s+0x%" PRIx64,
reloc->sym->sec->name, reloc->addend);
return -1;
}
} else {
- WARN("can't find reachable insn at %s+0x%x",
+ WARN("can't find reachable insn at %s+0x%" PRIx64,
reloc->sym->sec->name, reloc->addend);
return -1;
}
@@ -667,7 +670,7 @@ static int create_static_call_sections(struct objtool_file *file)
key_sym = find_symbol_by_name(file->elf, tmp);
if (!key_sym) {
- if (!module) {
+ if (!opts.module) {
WARN("static_call: can't find static_call_key symbol: %s", tmp);
return -1;
}
@@ -760,7 +763,7 @@ static int create_ibt_endbr_seal_sections(struct objtool_file *file)
list_for_each_entry(insn, &file->endbr_list, call_node)
idx++;
- if (stats) {
+ if (opts.stats) {
printf("ibt: ENDBR at function start: %d\n", file->nr_endbr);
printf("ibt: ENDBR inside functions: %d\n", file->nr_endbr_int);
printf("ibt: superfluous ENDBR: %d\n", idx);
@@ -1027,7 +1030,7 @@ static void add_uaccess_safe(struct objtool_file *file)
struct symbol *func;
const char **name;
- if (!uaccess)
+ if (!opts.uaccess)
return;
for (name = uaccess_safe_builtin; *name; name++) {
@@ -1143,7 +1146,7 @@ static void annotate_call_site(struct objtool_file *file,
* attribute so they need a little help, NOP out any such calls from
* noinstr text.
*/
- if (insn->sec->noinstr && sym->profiling_func) {
+ if (opts.hack_noinstr && insn->sec->noinstr && sym->profiling_func) {
if (reloc) {
reloc->type = R_NONE;
elf_write_reloc(file->elf, reloc);
@@ -1155,10 +1158,21 @@ static void annotate_call_site(struct objtool_file *file,
: arch_nop_insn(insn->len));
insn->type = sibling ? INSN_RETURN : INSN_NOP;
+
+ if (sibling) {
+ /*
+ * We've replaced the tail-call JMP insn by two new
+ * insn: RET; INT3, except we only have a single struct
+ * insn here. Mark it retpoline_safe to avoid the SLS
+ * warning, instead of adding another insn.
+ */
+ insn->retpoline_safe = true;
+ }
+
return;
}
- if (mcount && sym->fentry) {
+ if (opts.mcount && sym->fentry) {
if (sibling)
WARN_FUNC("Tail call to __fentry__ !?!?", insn->sec, insn->offset);
@@ -1239,11 +1253,20 @@ static bool same_function(struct instruction *insn1, struct instruction *insn2)
return insn1->func->pfunc == insn2->func->pfunc;
}
-static bool is_first_func_insn(struct instruction *insn)
+static bool is_first_func_insn(struct objtool_file *file, struct instruction *insn)
{
- return insn->offset == insn->func->offset ||
- (insn->type == INSN_ENDBR &&
- insn->offset == insn->func->offset + insn->len);
+ if (insn->offset == insn->func->offset)
+ return true;
+
+ if (opts.ibt) {
+ struct instruction *prev = prev_insn_same_sym(file, insn);
+
+ if (prev && prev->type == INSN_ENDBR &&
+ insn->offset == insn->func->offset + prev->len)
+ return true;
+ }
+
+ return false;
}
/*
@@ -1251,12 +1274,19 @@ static bool is_first_func_insn(struct instruction *insn)
*/
static int add_jump_destinations(struct objtool_file *file)
{
- struct instruction *insn;
+ struct instruction *insn, *jump_dest;
struct reloc *reloc;
struct section *dest_sec;
unsigned long dest_off;
for_each_insn(file, insn) {
+ if (insn->jump_dest) {
+ /*
+ * handle_group_alt() may have previously set
+ * 'jump_dest' for some alternatives.
+ */
+ continue;
+ }
if (!is_static_jump(insn))
continue;
@@ -1271,7 +1301,10 @@ static int add_jump_destinations(struct objtool_file *file)
add_retpoline_call(file, insn);
continue;
} else if (insn->func) {
- /* internal or external sibling call (with reloc) */
+ /*
+ * External sibling call or internal sibling call with
+ * STT_FUNC reloc.
+ */
add_call_dest(file, insn, reloc->sym, true);
continue;
} else if (reloc->sym->sec->idx) {
@@ -1283,17 +1316,8 @@ static int add_jump_destinations(struct objtool_file *file)
continue;
}
- insn->jump_dest = find_insn(file, dest_sec, dest_off);
- if (!insn->jump_dest) {
-
- /*
- * This is a special case where an alt instruction
- * jumps past the end of the section. These are
- * handled later in handle_group_alt().
- */
- if (!strcmp(insn->sec->name, ".altinstr_replacement"))
- continue;
-
+ jump_dest = find_insn(file, dest_sec, dest_off);
+ if (!jump_dest) {
WARN_FUNC("can't find jump dest instruction at %s+0x%lx",
insn->sec, insn->offset, dest_sec->name,
dest_off);
@@ -1303,8 +1327,8 @@ static int add_jump_destinations(struct objtool_file *file)
/*
* Cross-function jump.
*/
- if (insn->func && insn->jump_dest->func &&
- insn->func != insn->jump_dest->func) {
+ if (insn->func && jump_dest->func &&
+ insn->func != jump_dest->func) {
/*
* For GCC 8+, create parent/child links for any cold
@@ -1322,16 +1346,22 @@ static int add_jump_destinations(struct objtool_file *file)
* subfunction is through a jump table.
*/
if (!strstr(insn->func->name, ".cold") &&
- strstr(insn->jump_dest->func->name, ".cold")) {
- insn->func->cfunc = insn->jump_dest->func;
- insn->jump_dest->func->pfunc = insn->func;
+ strstr(jump_dest->func->name, ".cold")) {
+ insn->func->cfunc = jump_dest->func;
+ jump_dest->func->pfunc = insn->func;
- } else if (!same_function(insn, insn->jump_dest) &&
- is_first_func_insn(insn->jump_dest)) {
- /* internal sibling call (without reloc) */
- add_call_dest(file, insn, insn->jump_dest->func, true);
+ } else if (!same_function(insn, jump_dest) &&
+ is_first_func_insn(file, jump_dest)) {
+ /*
+ * Internal sibling call without reloc or with
+ * STT_SECTION reloc.
+ */
+ add_call_dest(file, insn, jump_dest->func, true);
+ continue;
}
}
+
+ insn->jump_dest = jump_dest;
}
return 0;
@@ -1520,13 +1550,13 @@ static int handle_group_alt(struct objtool_file *file,
continue;
dest_off = arch_jump_destination(insn);
- if (dest_off == special_alt->new_off + special_alt->new_len)
+ if (dest_off == special_alt->new_off + special_alt->new_len) {
insn->jump_dest = next_insn_same_sec(file, last_orig_insn);
-
- if (!insn->jump_dest) {
- WARN_FUNC("can't find alternative jump destination",
- insn->sec, insn->offset);
- return -1;
+ if (!insn->jump_dest) {
+ WARN_FUNC("can't find alternative jump destination",
+ insn->sec, insn->offset);
+ return -1;
+ }
}
}
@@ -1564,7 +1594,7 @@ static int handle_jump_alt(struct objtool_file *file,
return -1;
}
- if (special_alt->key_addend & 2) {
+ if (opts.hack_jump_label && special_alt->key_addend & 2) {
struct reloc *reloc = insn_reloc(file, orig_insn);
if (reloc) {
@@ -1671,7 +1701,7 @@ static int add_special_section_alts(struct objtool_file *file)
free(special_alt);
}
- if (stats) {
+ if (opts.stats) {
printf("jl\\\tNOP\tJMP\n");
printf("short:\t%ld\t%ld\n", file->jl_nop_short, file->jl_short);
printf("long:\t%ld\t%ld\n", file->jl_nop_long, file->jl_long);
@@ -1917,7 +1947,7 @@ static int read_unwind_hints(struct objtool_file *file)
insn->hint = true;
- if (ibt && hint->type == UNWIND_HINT_TYPE_REGS_PARTIAL) {
+ if (opts.ibt && hint->type == UNWIND_HINT_TYPE_REGS_PARTIAL) {
struct symbol *sym = find_symbol_by_offset(insn->sec, insn->offset);
if (sym && sym->bind == STB_GLOBAL &&
@@ -2225,14 +2255,14 @@ static int decode_sections(struct objtool_file *file)
return ret;
/*
- * Must be before add_special_section_alts() as that depends on
- * jump_dest being set.
+ * Must be before add_jump_destinations(), which depends on 'func'
+ * being set for alternatives, to enable proper sibling call detection.
*/
- ret = add_jump_destinations(file);
+ ret = add_special_section_alts(file);
if (ret)
return ret;
- ret = add_special_section_alts(file);
+ ret = add_jump_destinations(file);
if (ret)
return ret;
@@ -2778,7 +2808,7 @@ static int update_cfi_state(struct instruction *insn,
}
/* detect when asm code uses rbp as a scratch register */
- if (!no_fp && insn->func && op->src.reg == CFI_BP &&
+ if (opts.stackval && insn->func && op->src.reg == CFI_BP &&
cfa->base != CFI_BP)
cfi->bp_scratch = true;
break;
@@ -3154,115 +3184,6 @@ static struct instruction *next_insn_to_validate(struct objtool_file *file,
return next_insn_same_sec(file, insn);
}
-static struct instruction *
-validate_ibt_reloc(struct objtool_file *file, struct reloc *reloc)
-{
- struct instruction *dest;
- struct section *sec;
- unsigned long off;
-
- sec = reloc->sym->sec;
- off = reloc->sym->offset;
-
- if ((reloc->sec->base->sh.sh_flags & SHF_EXECINSTR) &&
- (reloc->type == R_X86_64_PC32 || reloc->type == R_X86_64_PLT32))
- off += arch_dest_reloc_offset(reloc->addend);
- else
- off += reloc->addend;
-
- dest = find_insn(file, sec, off);
- if (!dest)
- return NULL;
-
- if (dest->type == INSN_ENDBR) {
- if (!list_empty(&dest->call_node))
- list_del_init(&dest->call_node);
-
- return NULL;
- }
-
- if (reloc->sym->static_call_tramp)
- return NULL;
-
- return dest;
-}
-
-static void warn_noendbr(const char *msg, struct section *sec, unsigned long offset,
- struct instruction *dest)
-{
- WARN_FUNC("%srelocation to !ENDBR: %s+0x%lx", sec, offset, msg,
- dest->func ? dest->func->name : dest->sec->name,
- dest->func ? dest->offset - dest->func->offset : dest->offset);
-}
-
-static void validate_ibt_dest(struct objtool_file *file, struct instruction *insn,
- struct instruction *dest)
-{
- if (dest->func && dest->func == insn->func) {
- /*
- * Anything from->to self is either _THIS_IP_ or IRET-to-self.
- *
- * There is no sane way to annotate _THIS_IP_ since the compiler treats the
- * relocation as a constant and is happy to fold in offsets, skewing any
- * annotation we do, leading to vast amounts of false-positives.
- *
- * There's also compiler generated _THIS_IP_ through KCOV and
- * such which we have no hope of annotating.
- *
- * As such, blanket accept self-references without issue.
- */
- return;
- }
-
- if (dest->noendbr)
- return;
-
- warn_noendbr("", insn->sec, insn->offset, dest);
-}
-
-static void validate_ibt_insn(struct objtool_file *file, struct instruction *insn)
-{
- struct instruction *dest;
- struct reloc *reloc;
-
- switch (insn->type) {
- case INSN_CALL:
- case INSN_CALL_DYNAMIC:
- case INSN_JUMP_CONDITIONAL:
- case INSN_JUMP_UNCONDITIONAL:
- case INSN_JUMP_DYNAMIC:
- case INSN_JUMP_DYNAMIC_CONDITIONAL:
- case INSN_RETURN:
- /*
- * We're looking for code references setting up indirect code
- * flow. As such, ignore direct code flow and the actual
- * dynamic branches.
- */
- return;
-
- case INSN_NOP:
- /*
- * handle_group_alt() will create INSN_NOP instruction that
- * don't belong to any section, ignore all NOP since they won't
- * carry a (useful) relocation anyway.
- */
- return;
-
- default:
- break;
- }
-
- for (reloc = insn_reloc(file, insn);
- reloc;
- reloc = find_reloc_by_dest_range(file->elf, insn->sec,
- reloc->offset + 1,
- (insn->offset + insn->len) - (reloc->offset + 1))) {
- dest = validate_ibt_reloc(file, reloc);
- if (dest)
- validate_ibt_dest(file, insn, dest);
- }
-}
-
/*
* Follow the branch starting at the given instruction, and recursively follow
* any other branches (jumps). Meanwhile, track the frame pointer state at
@@ -3283,7 +3204,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
while (1) {
next_insn = next_insn_to_validate(file, insn);
- if (file->c_file && func && insn->func && func != insn->func->pfunc) {
+ if (func && insn->func && func != insn->func->pfunc) {
WARN("%s() falls through to next function %s()",
func->name, insn->func->name);
return 1;
@@ -3336,7 +3257,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
ret = validate_branch(file, func, alt->insn, state);
if (ret) {
- if (backtrace)
+ if (opts.backtrace)
BT_FUNC("(alt)", insn);
return ret;
}
@@ -3352,11 +3273,6 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
switch (insn->type) {
case INSN_RETURN:
- if (sls && !insn->retpoline_safe &&
- next_insn && next_insn->type != INSN_TRAP) {
- WARN_FUNC("missing int3 after ret",
- insn->sec, insn->offset);
- }
return validate_return(func, insn, &state);
case INSN_CALL:
@@ -3365,7 +3281,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
if (ret)
return ret;
- if (!no_fp && func && !is_fentry_call(insn) &&
+ if (opts.stackval && func && !is_fentry_call(insn) &&
!has_valid_stack_frame(&state)) {
WARN_FUNC("call without frame pointer save/setup",
sec, insn->offset);
@@ -3388,7 +3304,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
ret = validate_branch(file, func,
insn->jump_dest, state);
if (ret) {
- if (backtrace)
+ if (opts.backtrace)
BT_FUNC("(branch)", insn);
return ret;
}
@@ -3400,13 +3316,6 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
break;
case INSN_JUMP_DYNAMIC:
- if (sls && !insn->retpoline_safe &&
- next_insn && next_insn->type != INSN_TRAP) {
- WARN_FUNC("missing int3 after indirect jump",
- insn->sec, insn->offset);
- }
-
- /* fallthrough */
case INSN_JUMP_DYNAMIC_CONDITIONAL:
if (is_sibling_call(insn)) {
ret = validate_sibling_call(file, insn, &state);
@@ -3472,9 +3381,6 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
break;
}
- if (ibt)
- validate_ibt_insn(file, insn);
-
if (insn->dead_end)
return 0;
@@ -3501,7 +3407,7 @@ static int validate_unwind_hints(struct objtool_file *file, struct section *sec)
if (!file->hints)
return 0;
- init_insn_state(&state, sec);
+ init_insn_state(file, &state, sec);
if (sec) {
insn = find_insn(file, sec, 0);
@@ -3514,7 +3420,7 @@ static int validate_unwind_hints(struct objtool_file *file, struct section *sec)
while (&insn->list != &file->insn_list && (!sec || insn->sec == sec)) {
if (insn->hint && !insn->visited && !insn->ignore) {
ret = validate_branch(file, insn->func, insn, state);
- if (ret && backtrace)
+ if (ret && opts.backtrace)
BT_FUNC("<=== (hint)", insn);
warnings += ret;
}
@@ -3544,7 +3450,7 @@ static int validate_retpoline(struct objtool_file *file)
* loaded late, they very much do need retpoline in their
* .init.text
*/
- if (!strcmp(insn->sec->name, ".init.text") && !module)
+ if (!strcmp(insn->sec->name, ".init.text") && !opts.module)
continue;
WARN_FUNC("indirect %s found in RETPOLINE build",
@@ -3587,14 +3493,14 @@ static bool ignore_unreachable_insn(struct objtool_file *file, struct instructio
return true;
/*
- * Whole archive runs might encounder dead code from weak symbols.
+ * Whole archive runs might encounter dead code from weak symbols.
* This is where the linker will have dropped the weak symbol in
* favour of a regular symbol, but leaves the code in place.
*
* In this case we'll find a piece of code (whole function) that is not
* covered by a !section symbol. Ignore them.
*/
- if (!insn->func && lto) {
+ if (opts.link && !insn->func) {
int size = find_symbol_hole_containing(insn->sec, insn->offset);
unsigned long end = insn->offset + size;
@@ -3701,7 +3607,7 @@ static int validate_symbol(struct objtool_file *file, struct section *sec,
state->uaccess = sym->uaccess_safe;
ret = validate_branch(file, insn->func, insn, *state);
- if (ret && backtrace)
+ if (ret && opts.backtrace)
BT_FUNC("<=== (sym)", insn);
return ret;
}
@@ -3716,7 +3622,7 @@ static int validate_section(struct objtool_file *file, struct section *sec)
if (func->type != STT_FUNC)
continue;
- init_insn_state(&state, sec);
+ init_insn_state(file, &state, sec);
set_func_state(&state.cfi);
warnings += validate_symbol(file, sec, func, &state);
@@ -3725,7 +3631,7 @@ static int validate_section(struct objtool_file *file, struct section *sec)
return warnings;
}
-static int validate_vmlinux_functions(struct objtool_file *file)
+static int validate_noinstr_sections(struct objtool_file *file)
{
struct section *sec;
int warnings = 0;
@@ -3760,51 +3666,208 @@ static int validate_functions(struct objtool_file *file)
return warnings;
}
+static void mark_endbr_used(struct instruction *insn)
+{
+ if (!list_empty(&insn->call_node))
+ list_del_init(&insn->call_node);
+}
+
+static int validate_ibt_insn(struct objtool_file *file, struct instruction *insn)
+{
+ struct instruction *dest;
+ struct reloc *reloc;
+ unsigned long off;
+ int warnings = 0;
+
+ /*
+ * Looking for function pointer load relocations. Ignore
+ * direct/indirect branches:
+ */
+ switch (insn->type) {
+ case INSN_CALL:
+ case INSN_CALL_DYNAMIC:
+ case INSN_JUMP_CONDITIONAL:
+ case INSN_JUMP_UNCONDITIONAL:
+ case INSN_JUMP_DYNAMIC:
+ case INSN_JUMP_DYNAMIC_CONDITIONAL:
+ case INSN_RETURN:
+ case INSN_NOP:
+ return 0;
+ default:
+ break;
+ }
+
+ for (reloc = insn_reloc(file, insn);
+ reloc;
+ reloc = find_reloc_by_dest_range(file->elf, insn->sec,
+ reloc->offset + 1,
+ (insn->offset + insn->len) - (reloc->offset + 1))) {
+
+ /*
+ * static_call_update() references the trampoline, which
+ * doesn't have (or need) ENDBR. Skip warning in that case.
+ */
+ if (reloc->sym->static_call_tramp)
+ continue;
+
+ off = reloc->sym->offset;
+ if (reloc->type == R_X86_64_PC32 || reloc->type == R_X86_64_PLT32)
+ off += arch_dest_reloc_offset(reloc->addend);
+ else
+ off += reloc->addend;
+
+ dest = find_insn(file, reloc->sym->sec, off);
+ if (!dest)
+ continue;
+
+ if (dest->type == INSN_ENDBR) {
+ mark_endbr_used(dest);
+ continue;
+ }
+
+ if (dest->func && dest->func == insn->func) {
+ /*
+ * Anything from->to self is either _THIS_IP_ or
+ * IRET-to-self.
+ *
+ * There is no sane way to annotate _THIS_IP_ since the
+ * compiler treats the relocation as a constant and is
+ * happy to fold in offsets, skewing any annotation we
+ * do, leading to vast amounts of false-positives.
+ *
+ * There's also compiler generated _THIS_IP_ through
+ * KCOV and such which we have no hope of annotating.
+ *
+ * As such, blanket accept self-references without
+ * issue.
+ */
+ continue;
+ }
+
+ if (dest->noendbr)
+ continue;
+
+ WARN_FUNC("relocation to !ENDBR: %s",
+ insn->sec, insn->offset,
+ offstr(dest->sec, dest->offset));
+
+ warnings++;
+ }
+
+ return warnings;
+}
+
+static int validate_ibt_data_reloc(struct objtool_file *file,
+ struct reloc *reloc)
+{
+ struct instruction *dest;
+
+ dest = find_insn(file, reloc->sym->sec,
+ reloc->sym->offset + reloc->addend);
+ if (!dest)
+ return 0;
+
+ if (dest->type == INSN_ENDBR) {
+ mark_endbr_used(dest);
+ return 0;
+ }
+
+ if (dest->noendbr)
+ return 0;
+
+ WARN_FUNC("data relocation to !ENDBR: %s",
+ reloc->sec->base, reloc->offset,
+ offstr(dest->sec, dest->offset));
+
+ return 1;
+}
+
+/*
+ * Validate IBT rules and remove used ENDBR instructions from the seal list.
+ * Unused ENDBR instructions will be annotated for sealing (i.e., replaced with
+ * NOPs) later, in create_ibt_endbr_seal_sections().
+ */
static int validate_ibt(struct objtool_file *file)
{
struct section *sec;
struct reloc *reloc;
+ struct instruction *insn;
+ int warnings = 0;
+
+ for_each_insn(file, insn)
+ warnings += validate_ibt_insn(file, insn);
for_each_sec(file, sec) {
- bool is_data;
- /* already done in validate_branch() */
+ /* Already done by validate_ibt_insn() */
if (sec->sh.sh_flags & SHF_EXECINSTR)
continue;
if (!sec->reloc)
continue;
- if (!strncmp(sec->name, ".orc", 4))
+ /*
+ * These sections can reference text addresses, but not with
+ * the intent to indirect branch to them.
+ */
+ if (!strncmp(sec->name, ".discard", 8) ||
+ !strncmp(sec->name, ".debug", 6) ||
+ !strcmp(sec->name, ".altinstructions") ||
+ !strcmp(sec->name, ".ibt_endbr_seal") ||
+ !strcmp(sec->name, ".orc_unwind_ip") ||
+ !strcmp(sec->name, ".parainstructions") ||
+ !strcmp(sec->name, ".retpoline_sites") ||
+ !strcmp(sec->name, ".smp_locks") ||
+ !strcmp(sec->name, ".static_call_sites") ||
+ !strcmp(sec->name, "_error_injection_whitelist") ||
+ !strcmp(sec->name, "_kprobe_blacklist") ||
+ !strcmp(sec->name, "__bug_table") ||
+ !strcmp(sec->name, "__ex_table") ||
+ !strcmp(sec->name, "__jump_table") ||
+ !strcmp(sec->name, "__mcount_loc") ||
+ !strcmp(sec->name, "__tracepoints"))
continue;
- if (!strncmp(sec->name, ".discard", 8))
- continue;
+ list_for_each_entry(reloc, &sec->reloc->reloc_list, list)
+ warnings += validate_ibt_data_reloc(file, reloc);
+ }
- if (!strncmp(sec->name, ".debug", 6))
- continue;
+ return warnings;
+}
- if (!strcmp(sec->name, "_error_injection_whitelist"))
- continue;
+static int validate_sls(struct objtool_file *file)
+{
+ struct instruction *insn, *next_insn;
+ int warnings = 0;
- if (!strcmp(sec->name, "_kprobe_blacklist"))
- continue;
+ for_each_insn(file, insn) {
+ next_insn = next_insn_same_sec(file, insn);
- is_data = strstr(sec->name, ".data") || strstr(sec->name, ".rodata");
+ if (insn->retpoline_safe)
+ continue;
- list_for_each_entry(reloc, &sec->reloc->reloc_list, list) {
- struct instruction *dest;
+ switch (insn->type) {
+ case INSN_RETURN:
+ if (!next_insn || next_insn->type != INSN_TRAP) {
+ WARN_FUNC("missing int3 after ret",
+ insn->sec, insn->offset);
+ warnings++;
+ }
- dest = validate_ibt_reloc(file, reloc);
- if (is_data && dest && !dest->noendbr) {
- warn_noendbr("data ", reloc->sym->sec,
- reloc->sym->offset + reloc->addend,
- dest);
+ break;
+ case INSN_JUMP_DYNAMIC:
+ if (!next_insn || next_insn->type != INSN_TRAP) {
+ WARN_FUNC("missing int3 after indirect jump",
+ insn->sec, insn->offset);
+ warnings++;
}
+ break;
+ default:
+ break;
}
}
- return 0;
+ return warnings;
}
static int validate_reachable_instructions(struct objtool_file *file)
@@ -3829,16 +3892,6 @@ int check(struct objtool_file *file)
{
int ret, warnings = 0;
- if (lto && !(vmlinux || module)) {
- fprintf(stderr, "--lto requires: --vmlinux or --module\n");
- return 1;
- }
-
- if (ibt && !lto) {
- fprintf(stderr, "--ibt requires: --lto\n");
- return 1;
- }
-
arch_initial_func_cfi_state(&initial_func_cfi);
init_cfi_state(&init_cfi);
init_cfi_state(&func_cfi);
@@ -3859,73 +3912,89 @@ int check(struct objtool_file *file)
if (list_empty(&file->insn_list))
goto out;
- if (vmlinux && !lto) {
- ret = validate_vmlinux_functions(file);
+ if (opts.retpoline) {
+ ret = validate_retpoline(file);
if (ret < 0)
- goto out;
-
+ return ret;
warnings += ret;
- goto out;
}
- if (retpoline) {
- ret = validate_retpoline(file);
+ if (opts.stackval || opts.orc || opts.uaccess) {
+ ret = validate_functions(file);
if (ret < 0)
- return ret;
+ goto out;
warnings += ret;
- }
- ret = validate_functions(file);
- if (ret < 0)
- goto out;
- warnings += ret;
+ ret = validate_unwind_hints(file, NULL);
+ if (ret < 0)
+ goto out;
+ warnings += ret;
- ret = validate_unwind_hints(file, NULL);
- if (ret < 0)
- goto out;
- warnings += ret;
+ if (!warnings) {
+ ret = validate_reachable_instructions(file);
+ if (ret < 0)
+ goto out;
+ warnings += ret;
+ }
- if (ibt) {
+ } else if (opts.noinstr) {
+ ret = validate_noinstr_sections(file);
+ if (ret < 0)
+ goto out;
+ warnings += ret;
+ }
+
+ if (opts.ibt) {
ret = validate_ibt(file);
if (ret < 0)
goto out;
warnings += ret;
}
- if (!warnings) {
- ret = validate_reachable_instructions(file);
+ if (opts.sls) {
+ ret = validate_sls(file);
if (ret < 0)
goto out;
warnings += ret;
}
- ret = create_static_call_sections(file);
- if (ret < 0)
- goto out;
- warnings += ret;
+ if (opts.static_call) {
+ ret = create_static_call_sections(file);
+ if (ret < 0)
+ goto out;
+ warnings += ret;
+ }
- if (retpoline) {
+ if (opts.retpoline) {
ret = create_retpoline_sites_sections(file);
if (ret < 0)
goto out;
warnings += ret;
}
- if (mcount) {
+ if (opts.mcount) {
ret = create_mcount_loc_sections(file);
if (ret < 0)
goto out;
warnings += ret;
}
- if (ibt) {
+ if (opts.ibt) {
ret = create_ibt_endbr_seal_sections(file);
if (ret < 0)
goto out;
warnings += ret;
}
- if (stats) {
+ if (opts.orc && !list_empty(&file->insn_list)) {
+ ret = orc_create(file);
+ if (ret < 0)
+ goto out;
+ warnings += ret;
+ }
+
+
+ if (opts.stats) {
printf("nr_insns_visited: %ld\n", nr_insns_visited);
printf("nr_cfi: %ld\n", nr_cfi);
printf("nr_cfi_reused: %ld\n", nr_cfi_reused);