The JMP_NOSPEC macro branches to __x86_retpoline_*() rather than the
__x86_indirect_thunk_*() wrappers used by C code. Detect jumps to
__x86_retpoline_*() as retpoline dynamic jumps.
Presumably this doesn't trigger a user-visible bug. I only found it
when testing vmlinux.o validation.
Fixes: 39b735332cb8 ("objtool: Detect jumps to retpoline thunks")
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/31f5833e2e4f01e3d755889ac77e3661e906c09f.1611263461.git.jpoimboe@redhat.com
* replacement group.
*/
return insn->offset == special_alt->new_off &&
- (insn->type == INSN_CALL || is_static_jump(insn));
+ (insn->type == INSN_CALL || is_jump(insn));
}
/*
dest_sec = reloc->sym->sec;
dest_off = reloc->sym->sym.st_value +
arch_dest_reloc_offset(reloc->addend);
- } else if (strstr(reloc->sym->name, "_indirect_thunk_")) {
+ } else if (!strncmp(reloc->sym->name, "__x86_indirect_thunk_", 21) ||
+ !strncmp(reloc->sym->name, "__x86_retpoline_", 16)) {
/*
* Retpoline jumps are really dynamic jumps in
* disguise, so convert them accordingly.
insn->type == INSN_JUMP_UNCONDITIONAL;
}
+static inline bool is_dynamic_jump(struct instruction *insn)
+{
+ return insn->type == INSN_JUMP_DYNAMIC ||
+ insn->type == INSN_JUMP_DYNAMIC_CONDITIONAL;
+}
+
+static inline bool is_jump(struct instruction *insn)
+{
+ return is_static_jump(insn) || is_dynamic_jump(insn);
+}
+
struct instruction *find_insn(struct objtool_file *file,
struct section *sec, unsigned long offset);