Re: [dpdk-dev] [PATCH] mk: add support for UBSAN

[Harman Kalra <hkalra@marvell.com>]

Ping..

On Fri, Sep 13, 2019 at 11:40:40AM +0000, Harman Kalra wrote:
> Ping..
> Kindly review this patch.
> 
> On Mon, Aug 19, 2019 at 07:18:21PM +0530, Harman Kalra wrote:
> > UndefinedBehaviorSanitizer (UBSan) is a fast undefined behavior
> > detector. UBSan modifies the program at compile-time to catch
> > various kinds of undefined behavior during program execution.
> > 
> > This patch implements support for UBSan to the DPDK.
> > 
> > See: doc/guides/prog_guide/ubsan.rst for more information.
> > 
> > Signed-off-by: Harman Kalra <hkalra@marvell.com>
> > ---
> >  config/common_base                     |   6 ++
> >  config/meson.build                     |  15 ++++
> >  doc/guides/prog_guide/index.rst        |   1 +
> >  doc/guides/prog_guide/ubsan.rst        | 112 +++++++++++++++++++++++++
> >  doc/guides/rel_notes/release_19_11.rst |   7 ++
> >  meson_options.txt                      |   2 +
> >  mk/rte.app.mk                          |  10 +++
> >  mk/rte.lib.mk                          |  12 +++
> >  mk/toolchain/clang/rte.vars.mk         |   4 +
> >  mk/toolchain/gcc/rte.vars.mk           |   8 ++
> >  10 files changed, 177 insertions(+)
> >  create mode 100644 doc/guides/prog_guide/ubsan.rst
> > 
> > diff --git a/config/common_base b/config/common_base
> > index 8ef75c203..b47a6f28e 100644
> > --- a/config/common_base
> > +++ b/config/common_base
> > @@ -1067,3 +1067,9 @@ CONFIG_RTE_APP_CRYPTO_PERF=y
> >  # Compile the eventdev application
> >  #
> >  CONFIG_RTE_APP_EVENTDEV=y
> > +
> > +#
> > +# Enable undefined behavior sanitizer
> > +#
> > +CONFIG_RTE_UBSAN=n
> > +CONFIG_RTE_UBSAN_SANITIZE_ALL=n
> > diff --git a/config/meson.build b/config/meson.build
> > index 2bafea530..6a2fa117d 100644
> > --- a/config/meson.build
> > +++ b/config/meson.build
> > @@ -196,3 +196,18 @@ add_project_arguments('-D_GNU_SOURCE', language: 'c')
> >  if is_freebsd
> >  	add_project_arguments('-D__BSD_VISIBLE', language: 'c')
> >  endif
> > +
> > +# enable ubsan
> > +if get_option('enable_ubsan')
> > +	if cc.has_argument('-fsanitize=undefined')
> > +		ubsan_dep = cc.find_library('libubsan', required: false)
> > +		if ubsan_dep.found()
> > +			add_project_arguments('-fsanitize=undefined', language: 'c')
> > +			add_project_link_arguments('-fsanitize=undefined', language: 'c')
> > +		else
> > +			message('libubsan not found, UBSAN cannot be enabled')
> > +		endif
> > +	else
> > +		message('gcc version does not support UBSAN')
> > +	endif
> > +endif
> > diff --git a/doc/guides/prog_guide/index.rst b/doc/guides/prog_guide/index.rst
> > index 692409af8..970901e9a 100644
> > --- a/doc/guides/prog_guide/index.rst
> > +++ b/doc/guides/prog_guide/index.rst
> > @@ -66,4 +66,5 @@ Programmer's Guide
> >      perf_opt_guidelines
> >      writing_efficient_code
> >      profile_app
> > +    ubsan
> >      glossary
> > diff --git a/doc/guides/prog_guide/ubsan.rst b/doc/guides/prog_guide/ubsan.rst
> > new file mode 100644
> > index 000000000..cb19f3bd9
> > --- /dev/null
> > +++ b/doc/guides/prog_guide/ubsan.rst
> > @@ -0,0 +1,112 @@
> > +..  SPDX-License-Identifier: BSD-3-Clause
> > +    Copyright(c) 2019 Marvell International Ltd.
> > +
> > +The Undefined Behavior Sanitizer - UBSan
> > +========================================
> > +
> > +UndefinedBehaviorSanitizer (UBSan) is a runtime undefined behavior detector.
> > +UBSan uses compile-time instrumentation and modifies the program by adding
> > +some stubs which perform certain checks before operations that might cause
> > +undefined behaviour. If some UB detected, respective _UBSan_handle_* handlers
> > +(which are defined in libUBSan library) are called to prints the error message.
> > +
> > +Some examples of undefined behaviour checks:
> > +
> > +* Misaligned memory access
> > +* Signed integer overflow
> > +* Load from/store to an object with insufficient space.
> > +* Integer divide by zero as well as INT_MIN / -1 division
> > +* Out-of-bounds memory accesses.
> > +* Null argument declared with nonnull attribute, returned null from function
> > +  which never returns null, null ptr dereference
> > +* Variable size array with non-positive length
> > +
> > +GCC supports this feature since 4.9, however GCC 5.0 onwards has many more
> > +checkers implemented.
> > +
> > +Example UBSan error
> > +--------------------
> > +
> > +Following error was reported when UBSan was enabled:
> > +
> > +.. code-block:: console
> > +
> > +    drivers/net/octeontx2/otx2_stats.c:82:26: runtime error: left shift of
> > +    1 by 31 places cannot be represented in type 'int'
> > +
> > +Code responsible for this error:
> > +
> > +.. code-block:: c
> > +
> > +    if (dev->txmap[i] & (1 << 31)) {
> > +
> > +To fix this error:
> > +
> > +.. code-block:: c
> > +
> > +    if (dev->txmap[i] & (1U << 31)) {
> > +
> > +Usage
> > +-----
> > +
> > +make build
> > +^^^^^^^^^^
> > +
> > +To enable UBSan, enable following configuration:
> > +
> > +.. code-block:: console
> > +
> > +    CONFIG_RTE_UBSAN=y
> > +
> > +UBSan framework supports three modes:
> > +
> > +1. Enable UBSan on the entire DPDK source code - set following configuration:
> > +
> > +.. code-block:: console
> > +
> > +    CONFIG_RTE_UBSAN_SANITIZE_ALL=y
> > +
> > +2. Enable UBSan on a particular library or PMD - add the following line to the
> > +   respective Makefile of the library or PMD
> > +   (make sure ``CONFIG_RTE_UBSAN_SANITIZE_ALL=n``). This will instrument only
> > +   the library or PMD and not the entire repository.
> > +
> > +.. code-block:: console
> > +
> > +    UBSAN_SANITIZE := y
> > +
> > +3. Disable UBSan for a particular library or PMD - add the following line to
> > +   the respective Makefile of the library or PMD. Make sure
> > +   ``CONFIG_RTE_UBSAN_SANITIZE_ALL=y`` config is set. This will instrument
> > +   entire DPDK repository but not this specific library or PMD.
> > +
> > +.. code-block:: console
> > +
> > +    UBSAN_SANITIZE := n
> > +
> > +.. Note::
> > +
> > +  Standard DPDK applications like test, testpmd, etc. cannot be
> > +  chosen explicitly for UBSan check, like libraries or PMD. The reason is,
> > +  say UBSan is enabled for library X, and ``UBSAN_SANITIZE=y`` is not added
> > +  in Makefile of app Y which uses X APIs. This will lead to undefined
> > +  reference to _UBSan_handle_* handlers as Y is not compiled with UBSan flags.
> > +  Hence UBSan check is enabled for all standard DPDK applications as soon as
> > +  ``CONFIG_RTE_UBSAN=y`` is set.
> > +
> > +meson build
> > +^^^^^^^^^^^
> > +
> > +To enable UBSan in meson build system, use following meson build command:
> > +
> > +**Example usage:**
> > +
> > +.. code-block:: console
> > +
> > + meson build -Denable_ubsan=true
> > + ninja -C build
> > +
> > +.. Note::
> > +
> > +  Meson build works only in one mode i.e. UBSan can be enabled for
> > +  the entire DPDK sources and not individual libraries or PMD, like make build.
> > diff --git a/doc/guides/rel_notes/release_19_11.rst b/doc/guides/rel_notes/release_19_11.rst
> > index 8490d897c..cfefdbeec 100644
> > --- a/doc/guides/rel_notes/release_19_11.rst
> > +++ b/doc/guides/rel_notes/release_19_11.rst
> > @@ -56,6 +56,13 @@ New Features
> >       Also, make sure to start the actual text at the margin.
> >       =========================================================
> >  
> > +* **Added Undefined Behavior Sanitizer framework.**
> > +
> > +  UBSan is a fast runtime undefined behavior detector which uses compile-time
> > +  instrumentation and modifies the program by adding some stubs that perform
> > +  certain checks before operations that might cause undefined behavior.
> > +
> > +  See :doc:`../prog_guide/ubsan` for more information:
> >  
> >  Removed Items
> >  -------------
> > diff --git a/meson_options.txt b/meson_options.txt
> > index 448f3e63d..fb0aead00 100644
> > --- a/meson_options.txt
> > +++ b/meson_options.txt
> > @@ -8,6 +8,8 @@ option('enable_docs', type: 'boolean', value: false,
> >  	description: 'build documentation')
> >  option('enable_kmods', type: 'boolean', value: true,
> >  	description: 'build kernel modules')
> > +option('enable_ubsan', type: 'boolean', value: false,
> > +	description: 'Enables undefined behavior sanitizer')
> >  option('examples', type: 'string', value: '',
> >  	description: 'Comma-separated list of examples to build by default')
> >  option('flexran_sdk', type: 'string', value: '',
> > diff --git a/mk/rte.app.mk b/mk/rte.app.mk
> > index ba5c39e01..9ea421a83 100644
> > --- a/mk/rte.app.mk
> > +++ b/mk/rte.app.mk
> > @@ -374,6 +374,16 @@ endif
> >  
> >  MAPFLAGS = -Map=$@.map --cref
> >  
> > +#
> > +# If UBSAN is enabled, all application will be compiled with
> > +# '-fsanitize=undefined' flag
> > +#
> > +ifeq ($(CONFIG_RTE_UBSAN),y)
> > +ifeq ($(UBSAN_ENABLE),y)
> > +CFLAGS += -fsanitize=undefined
> > +endif
> > +endif
> > +
> >  .PHONY: all
> >  all: install
> >  
> > diff --git a/mk/rte.lib.mk b/mk/rte.lib.mk
> > index 4df8849a0..33f5746c8 100644
> > --- a/mk/rte.lib.mk
> > +++ b/mk/rte.lib.mk
> > @@ -29,6 +29,18 @@ CPU_LDFLAGS += --version-script=$(SRCDIR)/$(EXPORT_MAP)
> >  endif
> >  endif
> >  
> > +#
> > +# If UBSAN is enabled, lib to undergo check can be chosen
> > +# by setting UBSAN_SANITIZE=y in respective lib Makefile
> > +# else set CONFIG_RTE_UBSAN_SANITIZE_ALL=y to enforce check
> > +# on entire repo.
> > +#
> > +ifeq ($(CONFIG_RTE_UBSAN),y)
> > +ifeq ($(UBSAN_ENABLE),y)
> > +CFLAGS += $(if $(patsubst %n,,$(CONFIG_RTE_UBSAN_SANITIZE_ALL)$(UBSAN_SANITIZE)) \
> > +		, -fsanitize=undefined)
> > +endif
> > +endif
> >  
> >  _BUILD = $(LIB)
> >  PREINSTALL = $(SYMLINK-FILES-y)
> > diff --git a/mk/toolchain/clang/rte.vars.mk b/mk/toolchain/clang/rte.vars.mk
> > index 3c49dc568..623780106 100644
> > --- a/mk/toolchain/clang/rte.vars.mk
> > +++ b/mk/toolchain/clang/rte.vars.mk
> > @@ -56,5 +56,9 @@ ifeq ($(shell test $(CLANG_MAJOR_VERSION) -ge 4 && echo 1), 1)
> >  WERROR_FLAGS += -Wno-address-of-packed-member
> >  endif
> >  
> > +ifeq ($(CONFIG_RTE_UBSAN),y)
> > +UBSAN_ENABLE := y
> > +endif
> > +
> >  export CC AS AR LD OBJCOPY OBJDUMP STRIP READELF
> >  export TOOLCHAIN_CFLAGS TOOLCHAIN_LDFLAGS TOOLCHAIN_ASFLAGS
> > diff --git a/mk/toolchain/gcc/rte.vars.mk b/mk/toolchain/gcc/rte.vars.mk
> > index b852fcfd7..d40e14d61 100644
> > --- a/mk/toolchain/gcc/rte.vars.mk
> > +++ b/mk/toolchain/gcc/rte.vars.mk
> > @@ -90,5 +90,13 @@ endif
> >  # disable packed member unalign warnings
> >  WERROR_FLAGS += -Wno-address-of-packed-member
> >  
> > +ifeq ($(CONFIG_RTE_UBSAN),y)
> > +ifeq ($(shell test $(GCC_VERSION) -lt 49 && echo 1), 1)
> > +$(warning UBSAN not supported gcc < 4.9)
> > +else
> > +UBSAN_ENABLE = y
> > +endif
> > +endif
> > +
> >  export CC AS AR LD OBJCOPY OBJDUMP STRIP READELF
> >  export TOOLCHAIN_CFLAGS TOOLCHAIN_LDFLAGS TOOLCHAIN_ASFLAGS
> > -- 
> > 2.18.0
> >