This is a note to let you know that I've just added the patch titled lib/ubsan: add type mismatch handler for new GCC/Clang to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: lib-ubsan-add-type-mismatch-handler-for-new-gcc-clang.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 42440c1f9911b4b7b8ba3dc4e90c1197bc561211 Mon Sep 17 00:00:00 2001 From: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Date: Tue, 6 Feb 2018 15:40:42 -0800 Subject: lib/ubsan: add type mismatch handler for new GCC/Clang From: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> commit 42440c1f9911b4b7b8ba3dc4e90c1197bc561211 upstream. 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> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- lib/ubsan.c | 48 ++++++++++++++++++++++++++++++++++++++---------- lib/ubsan.h | 14 ++++++++++++++ 2 files changed, 52 insertions(+), 10 deletions(-) --- a/lib/ubsan.c +++ b/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; --- a/lib/ubsan.h +++ b/lib/ubsan.h @@ -36,6 +36,20 @@ 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; Patches currently in stable-queue which might be from aryabinin@xxxxxxxxxxxxx are queue-4.9/lib-ubsan-add-type-mismatch-handler-for-new-gcc-clang.patch queue-4.9/lib-ubsan.c-s-missaligned-misaligned.patch