From: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Subject: lib/ubsan: add type mismatch handler for new GCC/Clang
UBSAN=y fails to build with new GCC/clang:
arch/x86/kernel/head64.o: In function `sanitize_boot_params':
arch/x86/include/asm/bootparam_utils.h:37: undefined reference to `__ubsan_handle_type_mismatch_v1'
because Clang and GCC 8 slightly changed ABI for 'type mismatch' errors.
Compiler now uses new __ubsan_handle_type_mismatch_v1() function with
slightly modified 'struct type_mismatch_data'.
Let's add new 'struct type_mismatch_data_common' which is independent from
compiler's layout of 'struct type_mismatch_data'. And make
__ubsan_handle_type_mismatch[_v1]() functions transform compiler-dependent
type mismatch data to our internal representation. This way, we can
support both old and new compilers with minimal amount of change.
Link: http://lkml.kernel.org/r/20180119152853.16806-1-aryabinin@xxxxxxxxxxxxx
Signed-off-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Reported-by: Sodagudi Prasad <psodagud@xxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> [4.5+]
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/ubsan.c | 48 ++++++++++++++++++++++++++++++++++++++----------
lib/ubsan.h | 14 ++++++++++++++
2 files changed, 52 insertions(+), 10 deletions(-)
diff -puN lib/ubsan.c~lib-ubsan-add-type-mismatch-handler-for-new-gcc-clang lib/ubsan.c
--- a/lib/ubsan.c~lib-ubsan-add-type-mismatch-handler-for-new-gcc-clang
+++ a/lib/ubsan.c
@@ -265,14 +265,14 @@ void __ubsan_handle_divrem_overflow(stru
}
EXPORT_SYMBOL(__ubsan_handle_divrem_overflow);
-static void handle_null_ptr_deref(struct type_mismatch_data *data)
+static void handle_null_ptr_deref(struct type_mismatch_data_common *data)
{
unsigned long flags;
- if (suppress_report(&data->location))
+ if (suppress_report(data->location))
return;
- ubsan_prologue(&data->location, &flags);
+ ubsan_prologue(data->location, &flags);
pr_err("%s null pointer of type %s\n",
type_check_kinds[data->type_check_kind],
@@ -281,15 +281,15 @@ static void handle_null_ptr_deref(struct
ubsan_epilogue(&flags);
}
-static void handle_misaligned_access(struct type_mismatch_data *data,
+static void handle_misaligned_access(struct type_mismatch_data_common *data,
unsigned long ptr)
{
unsigned long flags;
- if (suppress_report(&data->location))
+ if (suppress_report(data->location))
return;
- ubsan_prologue(&data->location, &flags);
+ ubsan_prologue(data->location, &flags);
pr_err("%s misaligned address %p for type %s\n",
type_check_kinds[data->type_check_kind],
@@ -299,15 +299,15 @@ static void handle_misaligned_access(str
ubsan_epilogue(&flags);
}
-static void handle_object_size_mismatch(struct type_mismatch_data *data,
+static void handle_object_size_mismatch(struct type_mismatch_data_common *data,
unsigned long ptr)
{
unsigned long flags;
- if (suppress_report(&data->location))
+ if (suppress_report(data->location))
return;
- ubsan_prologue(&data->location, &flags);
+ ubsan_prologue(data->location, &flags);
pr_err("%s address %p with insufficient space\n",
type_check_kinds[data->type_check_kind],
(void *) ptr);
@@ -315,7 +315,7 @@ static void handle_object_size_mismatch(
ubsan_epilogue(&flags);
}
-void __ubsan_handle_type_mismatch(struct type_mismatch_data *data,
+static void ubsan_type_mismatch_common(struct type_mismatch_data_common *data,
unsigned long ptr)
{
@@ -326,8 +326,36 @@ void __ubsan_handle_type_mismatch(struct
else
handle_object_size_mismatch(data, ptr);
}
+
+void __ubsan_handle_type_mismatch(struct type_mismatch_data *data,
+ unsigned long ptr)
+{
+ struct type_mismatch_data_common common_data = {
+ .location = &data->location,
+ .type = data->type,
+ .alignment = data->alignment,
+ .type_check_kind = data->type_check_kind
+ };
+
+ ubsan_type_mismatch_common(&common_data, ptr);
+}
EXPORT_SYMBOL(__ubsan_handle_type_mismatch);
+void __ubsan_handle_type_mismatch_v1(struct type_mismatch_data_v1 *data,
+ unsigned long ptr)
+{
+
+ struct type_mismatch_data_common common_data = {
+ .location = &data->location,
+ .type = data->type,
+ .alignment = 1UL << data->log_alignment,
+ .type_check_kind = data->type_check_kind
+ };
+
+ ubsan_type_mismatch_common(&common_data, ptr);
+}
+EXPORT_SYMBOL(__ubsan_handle_type_mismatch_v1);
+
void __ubsan_handle_nonnull_return(struct nonnull_return_data *data)
{
unsigned long flags;
diff -puN lib/ubsan.h~lib-ubsan-add-type-mismatch-handler-for-new-gcc-clang lib/ubsan.h
--- a/lib/ubsan.h~lib-ubsan-add-type-mismatch-handler-for-new-gcc-clang
+++ a/lib/ubsan.h
@@ -37,6 +37,20 @@ struct type_mismatch_data {
unsigned char type_check_kind;
};
+struct type_mismatch_data_v1 {
+ struct source_location location;
+ struct type_descriptor *type;
+ unsigned char log_alignment;
+ unsigned char type_check_kind;
+};
+
+struct type_mismatch_data_common {
+ struct source_location *location;
+ struct type_descriptor *type;
+ unsigned long alignment;
+ unsigned char type_check_kind;
+};
+
struct nonnull_arg_data {
struct source_location location;
struct source_location attr_location;
_