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FPR:; SPF:None; LANG:en; PTR:InfoNoRecords; A:1; MX:1; received-spf: None (protection.outlook.com: marvell.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: BfekG2YqIW9SZIOqbNus0hCQy9Nxkb74pJ0jDTecxGZpL+3amuFx6fe8VwDFhJy+Brvkfr7XY/ZQKiFm27TisijVIDy32Q2t7Zf2Scb/XE4/Ej6UzHnbuRgKeOl2jWwmE1KKli3Icn0J1p5jOjO4Xf08uN4FFypxnMn8WAa0MVAfcz2TT4PQVfFUxm9L848puw2KenA8VBj5VjgfuPYyHcReXmPxYGlcVHYexp5wFHwIL/udN0YlhKekOKQPZ4rW9GK+ZG7j1pcj/B7TXxk6UwBwQhBSFAPufjFQEXvss+03znx9INtMf521n1XD4EX5oGkoBdtdOnGzkdxuUeWh5tT6X5jzlkhm/9E0rjImouLR54MQjMQPGjhV4xSvL1qglc7/FGX60CPibxkgEt7etn4QSKfMGlwe5tM1/JW22jQ= x-ms-exchange-transport-forked: True Content-Type: text/plain; charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-Network-Message-Id: c3864afa-8f4d-4c59-5c42-08d7383f3408 X-MS-Exchange-CrossTenant-originalarrivaltime: 13 Sep 2019 11:40:40.4991 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 70e1fb47-1155-421d-87fc-2e58f638b6e0 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: IYRW41kFbxQvR/WygytG5akN/sRCN5bbmeNqLIPFuBnr+6tjbuVuEpVHo/6btU94Q0Q+AFvYVMmXRcj+OLWy9w== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR18MB2880 X-OriginatorOrg: marvell.com X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.70,1.0.8 definitions=2019-09-13_06:2019-09-11,2019-09-13 signatures=0 Subject: Re: [dpdk-dev] [PATCH] mk: add support for UBSAN X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 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. >=20 > This patch implements support for UBSan to the DPDK. >=20 > See: doc/guides/prog_guide/ubsan.rst for more information. >=20 > Signed-off-by: Harman Kalra > --- > 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 >=20 > 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=3Dy > # Compile the eventdev application > # > CONFIG_RTE_APP_EVENTDEV=3Dy > + > +# > +# Enable undefined behavior sanitizer > +# > +CONFIG_RTE_UBSAN=3Dn > +CONFIG_RTE_UBSAN_SANITIZE_ALL=3Dn > 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=3Dundefined') > + ubsan_dep =3D cc.find_library('libubsan', required: false) > + if ubsan_dep.found() > + add_project_arguments('-fsanitize=3Dundefined', language: 'c') > + add_project_link_arguments('-fsanitize=3Dundefined', 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/inde= x.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/ubsa= n.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 > +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > + > +UndefinedBehaviorSanitizer (UBSan) is a runtime undefined behavior detec= tor. > +UBSan uses compile-time instrumentation and modifies the program by addi= ng > +some stubs which perform certain checks before operations that might cau= se > +undefined behaviour. If some UB detected, respective _UBSan_handle_* han= dlers > +(which are defined in libUBSan library) are called to prints the error m= essage. > + > +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 func= tion > + 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 mo= re > +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=3Dy > + > +UBSan framework supports three modes: > + > +1. Enable UBSan on the entire DPDK source code - set following configura= tion: > + > +.. code-block:: console > + > + CONFIG_RTE_UBSAN_SANITIZE_ALL=3Dy > + > +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=3Dn``). This will instrume= nt only > + the library or PMD and not the entire repository. > + > +.. code-block:: console > + > + UBSAN_SANITIZE :=3D y > + > +3. Disable UBSan for a particular library or PMD - add the following lin= e to > + the respective Makefile of the library or PMD. Make sure > + ``CONFIG_RTE_UBSAN_SANITIZE_ALL=3Dy`` config is set. This will instru= ment > + entire DPDK repository but not this specific library or PMD. > + > +.. code-block:: console > + > + UBSAN_SANITIZE :=3D n > + > +.. Note:: > + > + Standard DPDK applications like test, testpmd, etc. cannot be > + chosen explicitly for UBSan check, like libraries or PMD. The reason i= s, > + say UBSan is enabled for library X, and ``UBSAN_SANITIZE=3Dy`` 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 soo= n as > + ``CONFIG_RTE_UBSAN=3Dy`` 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=3Dtrue > + 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_note= s/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. > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > =20 > +* **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 per= form > + certain checks before operations that might cause undefined behavior. > + > + See :doc:`../prog_guide/ubsan` for more information: > =20 > 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 > =20 > MAPFLAGS =3D -Map=3D$@.map --cref > =20 > +# > +# If UBSAN is enabled, all application will be compiled with > +# '-fsanitize=3Dundefined' flag > +# > +ifeq ($(CONFIG_RTE_UBSAN),y) > +ifeq ($(UBSAN_ENABLE),y) > +CFLAGS +=3D -fsanitize=3Dundefined > +endif > +endif > + > .PHONY: all > all: install > =20 > diff --git a/mk/rte.lib.mk b/mk/rte.lib.mk > index 4df8849a0..33f5746c8 100644 > --- a/mk/rte.lib.mk > +++ b/mk/rte.lib.mk > @@ -29,6 +29,18 @@ CPU_LDFLAGS +=3D --version-script=3D$(SRCDIR)/$(EXPORT= _MAP) > endif > endif > =20 > +# > +# If UBSAN is enabled, lib to undergo check can be chosen > +# by setting UBSAN_SANITIZE=3Dy in respective lib Makefile > +# else set CONFIG_RTE_UBSAN_SANITIZE_ALL=3Dy to enforce check > +# on entire repo. > +# > +ifeq ($(CONFIG_RTE_UBSAN),y) > +ifeq ($(UBSAN_ENABLE),y) > +CFLAGS +=3D $(if $(patsubst %n,,$(CONFIG_RTE_UBSAN_SANITIZE_ALL)$(UBSAN_= SANITIZE)) \ > + , -fsanitize=3Dundefined) > +endif > +endif > =20 > _BUILD =3D $(LIB) > PREINSTALL =3D $(SYMLINK-FILES-y) > diff --git a/mk/toolchain/clang/rte.vars.mk b/mk/toolchain/clang/rte.vars= .mk > index 3c49dc568..623780106 100644 > --- a/mk/toolchain/clang/rte.vars.mk > +++ b/mk/toolchain/clang/rte.vars.mk > @@ -56,5 +56,9 @@ ifeq ($(shell test $(CLANG_MAJOR_VERSION) -ge 4 && echo= 1), 1) > WERROR_FLAGS +=3D -Wno-address-of-packed-member > endif > =20 > +ifeq ($(CONFIG_RTE_UBSAN),y) > +UBSAN_ENABLE :=3D 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 +=3D -Wno-address-of-packed-member > =20 > +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 =3D y > +endif > +endif > + > export CC AS AR LD OBJCOPY OBJDUMP STRIP READELF > export TOOLCHAIN_CFLAGS TOOLCHAIN_LDFLAGS TOOLCHAIN_ASFLAGS > --=20 > 2.18.0 >=20