From: Josh Poimboeuf jpoimboe@redhat.com
stable inclusion from stable-v5.10.133 commit e9197d768f976199a2356842400df947b4007377 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5PTAS CVE: CVE-2022-29900,CVE-2022-23816,CVE-2022-29901
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit b23cc71c62747f2e4c3e56138872cf47e1294f8a upstream.
Create a new struct associated with each group of alternatives instructions. This will help with the removal of fake jumps, and more importantly with adding support for stack layout changes in alternatives.
Signed-off-by: Josh Poimboeuf jpoimboe@redhat.com Signed-off-by: Ben Hutchings ben@decadent.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Lin Yujun linyujun809@huawei.com Reviewed-by: Zhang Jianhua chris.zjh@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- tools/objtool/check.c | 29 +++++++++++++++++++++++------ tools/objtool/check.h | 13 ++++++++++++- 2 files changed, 35 insertions(+), 7 deletions(-)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 8932f41c387f..6143a0790aa4 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1012,20 +1012,28 @@ static int handle_group_alt(struct objtool_file *file, struct instruction *orig_insn, struct instruction **new_insn) { - static unsigned int alt_group_next_index = 1; struct instruction *last_orig_insn, *last_new_insn, *insn, *fake_jump = NULL; - unsigned int alt_group = alt_group_next_index++; + struct alt_group *orig_alt_group, *new_alt_group; unsigned long dest_off;
+ + orig_alt_group = malloc(sizeof(*orig_alt_group)); + if (!orig_alt_group) { + WARN("malloc failed"); + return -1; + } last_orig_insn = NULL; insn = orig_insn; sec_for_each_insn_from(file, insn) { if (insn->offset >= special_alt->orig_off + special_alt->orig_len) break;
- insn->alt_group = alt_group; + insn->alt_group = orig_alt_group; last_orig_insn = insn; } + orig_alt_group->orig_group = NULL; + orig_alt_group->first_insn = orig_insn; + orig_alt_group->last_insn = last_orig_insn;
if (next_insn_same_sec(file, last_orig_insn)) { fake_jump = malloc(sizeof(*fake_jump)); @@ -1056,8 +1064,13 @@ static int handle_group_alt(struct objtool_file *file, return 0; }
+ new_alt_group = malloc(sizeof(*new_alt_group)); + if (!new_alt_group) { + WARN("malloc failed"); + return -1; + } + last_new_insn = NULL; - alt_group = alt_group_next_index++; insn = *new_insn; sec_for_each_insn_from(file, insn) { struct reloc *alt_reloc; @@ -1069,7 +1082,7 @@ static int handle_group_alt(struct objtool_file *file,
insn->ignore = orig_insn->ignore_alts; insn->func = orig_insn->func; - insn->alt_group = alt_group; + insn->alt_group = new_alt_group;
/* * Since alternative replacement code is copy/pasted by the @@ -1118,6 +1131,10 @@ static int handle_group_alt(struct objtool_file *file, return -1; }
+ new_alt_group->orig_group = orig_alt_group; + new_alt_group->first_insn = *new_insn; + new_alt_group->last_insn = last_new_insn; + if (fake_jump) list_add(&fake_jump->list, &last_new_insn->list);
@@ -2440,7 +2457,7 @@ static int validate_return(struct symbol *func, struct instruction *insn, struct static void fill_alternative_cfi(struct objtool_file *file, struct instruction *insn) { struct instruction *first_insn = insn; - int alt_group = insn->alt_group; + struct alt_group *alt_group = insn->alt_group;
sec_for_each_insn_continue(file, insn) { if (insn->alt_group != alt_group) diff --git a/tools/objtool/check.h b/tools/objtool/check.h index c280880f5eb4..dbf9f34622e8 100644 --- a/tools/objtool/check.h +++ b/tools/objtool/check.h @@ -19,6 +19,17 @@ struct insn_state { s8 instr; };
+struct alt_group { + /* + * Pointer from a replacement group to the original group. NULL if it + * *is* the original group. + */ + struct alt_group *orig_group; + + /* First and last instructions in the group */ + struct instruction *first_insn, *last_insn; +}; + struct instruction { struct list_head list; struct hlist_node hash; @@ -34,7 +45,7 @@ struct instruction { s8 instr; u8 visited; u8 ret_offset; - int alt_group; + struct alt_group *alt_group; struct symbol *call_dest; struct instruction *jump_dest; struct instruction *first_jump_src;