kpatch/0013-livepatch-patch-hook-support-force-enable-disable.patch
Zhipeng Xie 4424f7bf7e rebase from upstream v0.9.5
Signed-off-by: Zhipeng Xie <xiezhipeng1@huawei.com>
2021-11-19 12:02:33 +08:00

155 lines
5.9 KiB
Diff

From 88d2a5c88fcab0016db9347fbab41a22b9fb9a52 Mon Sep 17 00:00:00 2001
From: Zhipeng Xie <xiezhipeng1@huawei.com>
Date: Wed, 26 Feb 2020 20:43:34 -0500
Subject: [PATCH 13/24] livepatch-patch-hook: support force enable/disable
we use force to indicate function which bypass stack check
Signed-off-by: Zhipeng Xie <xiezhipeng1@huawei.com>
---
kmod/patch/kpatch-patch.h | 1 +
kmod/patch/livepatch-patch-hook.c | 17 +++++++++++++++++
kpatch-build/kpatch-build | 24 ++++++++++++++++++++----
3 files changed, 38 insertions(+), 4 deletions(-)
diff --git a/kmod/patch/kpatch-patch.h b/kmod/patch/kpatch-patch.h
index 9df7818..6e39364 100644
--- a/kmod/patch/kpatch-patch.h
+++ b/kmod/patch/kpatch-patch.h
@@ -64,4 +64,5 @@ struct kpatch_post_unpatch_callback {
char *objname;
};
+extern unsigned long __kpatch_force_funcs[], __kpatch_force_funcs_end[];
#endif /* _KPATCH_PATCH_H_ */
diff --git a/kmod/patch/livepatch-patch-hook.c b/kmod/patch/livepatch-patch-hook.c
index b578ef3..71439d9 100644
--- a/kmod/patch/livepatch-patch-hook.c
+++ b/kmod/patch/livepatch-patch-hook.c
@@ -432,6 +432,16 @@ extern struct kpatch_patch_func __kpatch_funcs[], __kpatch_funcs_end[];
extern struct kpatch_patch_dynrela __kpatch_dynrelas[], __kpatch_dynrelas_end[];
#endif
+static int patch_is_func_forced(unsigned long addr)
+{
+ unsigned long *a;
+
+ for (a = __kpatch_force_funcs; a < __kpatch_force_funcs_end; a++)
+ if (*a == addr)
+ return 1;
+ return 0;
+}
+
static int __init patch_init(void)
{
struct kpatch_patch_func *kfunc;
@@ -520,6 +530,13 @@ static int __init patch_init(void)
lfunc = &lfuncs[j];
lfunc->old_name = func->kfunc->name;
lfunc->new_func = (void *)func->kfunc->new_addr;
+#if defined(__KLP_SUPPORT_FORCE__)
+#ifdef __ALL_FORCE__
+ lfunc->force = 1;
+#else
+ lfunc->force = patch_is_func_forced(func->kfunc->new_addr);
+#endif
+#endif
#ifdef HAVE_SYMPOS
lfunc->old_sympos = func->kfunc->sympos;
#else
diff --git a/kpatch-build/kpatch-build b/kpatch-build/kpatch-build
index 722d362..9a98bfc 100755
--- a/kpatch-build/kpatch-build
+++ b/kpatch-build/kpatch-build
@@ -383,28 +383,32 @@ find_special_section_data_aarch64() {
# shellcheck disable=SC2086
SPECIAL_VARS="$(readelf -wi "$VMLINUX" |
gawk --non-decimal-data $AWK_OPTIONS '
- BEGIN { a = b = e = j = 0 }
+ BEGIN { a = b = e = j = c = f = 0 }
# Set state if name matches
a == 0 && /DW_AT_name.* alt_instr[[:space:]]*$/ {a = 1; next}
b == 0 && /DW_AT_name.* bug_entry[[:space:]]*$/ {b = 1; next}
e == 0 && /DW_AT_name.* exception_table_entry[[:space:]]*$/ {e = 1; next}
j == 0 && /DW_AT_name.* jump_entry[[:space:]]*$/ {j = 1; next}
+ c == 0 && /DW_AT_name.* klp_func[[:space:]]*$/ {c = 1; next}
# Reset state unless this abbrev describes the struct size
a == 1 && !/DW_AT_byte_size/ { a = 0; next }
b == 1 && !/DW_AT_byte_size/ { b = 0; next }
e == 1 && !/DW_AT_byte_size/ { e = 0; next }
j == 1 && !/DW_AT_byte_size/ { j = 0; next }
+ c == 1 && /DW_TAG_structure_type/ { c = 3; next }
+ c == 1 && /DW_AT_name.* force[[:space:]]*$/ {f = 2; next}
# Now that we know the size, stop parsing for it
a == 1 {printf("export ALT_STRUCT_SIZE=%d\n", $4); a = 2}
b == 1 {printf("export BUG_STRUCT_SIZE=%d\n", $4); b = 2}
e == 1 {printf("export EX_STRUCT_SIZE=%d\n", $4); e = 2}
j == 1 {printf("export JUMP_STRUCT_SIZE=%d\n", $4); j = 2}
+ f == 2 {printf("export KLP_SUPPORT_FORCE=y\n"); f = 3}
# Bail out once we have everything
- a == 2 && b == 2 && e == 2 && (j == 2 || skip_j) {exit}')"
+ a == 2 && b == 2 && e == 2 && (j == 2 || skip_j) && c == 3 {exit}')"
[[ -n "$SPECIAL_VARS" ]] && eval "$SPECIAL_VARS"
@@ -437,7 +441,7 @@ find_special_section_data() {
# shellcheck disable=SC2086
SPECIAL_VARS="$(readelf -wi "$VMLINUX" |
gawk --non-decimal-data $AWK_OPTIONS '
- BEGIN { a = b = p = e = o = j = s = i = 0 }
+ BEGIN { a = b = p = e = o = j = s = i = c = f = 0 }
# Set state if name matches
a == 0 && /DW_AT_name.* alt_instr[[:space:]]*$/ {a = 1; next}
@@ -448,6 +452,7 @@ find_special_section_data() {
j == 0 && /DW_AT_name.* jump_entry[[:space:]]*$/ {j = 1; next}
s == 0 && /DW_AT_name.* static_call_site[[:space:]]*$/ {s = 1; next}
i == 0 && /DW_AT_name.* pi_entry[[:space:]]*$/ {i = 1; next}
+ c == 0 && /DW_AT_name.* klp_func[[:space:]]*$/ {c = 1; next}
# Reset state unless this abbrev describes the struct size
a == 1 && !/DW_AT_byte_size/ { a = 0; next }
@@ -458,6 +463,8 @@ find_special_section_data() {
j == 1 && !/DW_AT_byte_size/ { j = 0; next }
s == 1 && !/DW_AT_byte_size/ { s = 0; next }
i == 1 && !/DW_AT_byte_size/ { i = 0; next }
+ c == 1 && /DW_TAG_structure_type/ { c = 3; next }
+ c == 1 && /DW_AT_name.* force[[:space:]]*$/ {f = 2; next}
# Now that we know the size, stop parsing for it
a == 1 {printf("export ALT_STRUCT_SIZE=%d\n", $4); a = 2}
@@ -468,9 +475,10 @@ find_special_section_data() {
j == 1 {printf("export JUMP_STRUCT_SIZE=%d\n", $4); j = 2}
s == 1 {printf("export STATIC_CALL_STRUCT_SIZE=%d\n", $4); s = 2}
i == 1 {printf("export PRINTK_INDEX_STRUCT_SIZE=%d\n", $4); i = 2}
+ f == 2 {printf("export KLP_SUPPORT_FORCE=y\n"); f = 3}
# Bail out once we have everything
- a == 2 && b == 2 && (p == 2 || skip_p) && e == 2 && (o == 2 || skip_o) && (j == 2 || skip_j) && (s == 2 || skip_s) && (i == 2 || skip_i) {exit}')"
+ a == 2 && b == 2 && (p == 2 || skip_p) && e == 2 && (o == 2 || skip_o) && (j == 2 || skip_j) && (s == 2 || skip_s) && (i == 2 || skip_i) && c == 3 {exit}')"
[[ -n "$SPECIAL_VARS" ]] && eval "$SPECIAL_VARS"
@@ -1231,6 +1239,14 @@ if [[ -n "$DISABLE_AFTER_LOAD" ]];then
export KCPPFLAGS="-DDISABLE_AFTER_LOAD $KCPPFLAGS"
fi
+if [[ -n "$NO_STACK_CHECK" ]];then
+ export KCPPFLAGS="-D__ALL_FORCE__ $KCPPFLAGS"
+fi
+
+if [[ -n "$KLP_SUPPORT_FORCE" ]];then
+ export KCPPFLAGS="-D__KLP_SUPPORT_FORCE__ $KCPPFLAGS"
+fi
+
save_env
echo "Building patch module: $MODNAME.ko"
--
2.23.0