# git rev-parse -q --verify f45c105149f3ea8f1d96d43fe45b7fba65535077^{commit} f45c105149f3ea8f1d96d43fe45b7fba65535077 already have revision, skipping fetch # git checkout -q -f -B kisskb f45c105149f3ea8f1d96d43fe45b7fba65535077 # git clean -qxdf # < git log -1 # commit f45c105149f3ea8f1d96d43fe45b7fba65535077 # Author: Gustavo A. R. Silva # Date: Fri Apr 24 09:07:40 2020 -0500 # # treewide: Replace zero-length array with flexible-array member # # The current codebase makes use of the zero-length array language # extension to the C90 standard, but the preferred mechanism to declare # variable-length types such as these ones is a flexible array member[1][2], # introduced in C99: # # struct foo { # int stuff; # struct boo array[]; # }; # # By making use of the mechanism above, we will get a compiler warning # in case the flexible array does not occur last in the structure, which # will help us prevent some kind of undefined behavior bugs from being # inadvertently introduced[3] to the codebase from now on. # # Also, notice that, dynamic memory allocations won't be affected by # this change: # # "Flexible array members have incomplete type, and so the sizeof operator # may not be applied. As a quirk of the original implementation of # zero-length arrays, sizeof evaluates to zero."[1] # # sizeof(flexible-array-member) triggers a warning because flexible array # members have incomplete type[1]. There are some instances of code in # which the sizeof operator is being incorrectly/erroneously applied to # zero-length arrays and the result is zero. Such instances may be hiding # some bugs. So, this work (flexible-array member conversions) will also # help to get completely rid of those sorts of issues. # # Notice that, currently, more than 250 of these patches have already # been merged into mainline during the last merge window, including # 5.7-rc2. So, in order to make better use of everyone's time, I'm # planning to add this treewide patch to my -next tree and then send a # pull request to Linus for 5.7-rc3 or -rc4, after getting some acks # and/or reviews. # # This treewide patch has been successfully built (on top of v5.7-rc1) for # multiple architectures (arm, arm64, sparc, powerpc, ia64, s390, i386, # nios2, c6x, xtensa, openrisc, mips, parisc, x86_64, riscv, sh, sparc64) # and 82 different configurations with the help of the 0-day CI guys[5]. # # This issue was found with the help of Coccinelle. # # [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html # [2] https://github.com/KSPP/linux/issues/21 # [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") # [4] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/?qt=grep&q=replace+zero-length+array+with+flexible-array+member # [5] https://github.com/GustavoARSilva/linux-hardening/blob/master/cii/kernel-ci/kspp-fam0-20200420.md # # Signed-off-by: Gustavo A. R. Silva # < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux-ld --version # < git log --format=%s --max-count=1 f45c105149f3ea8f1d96d43fe45b7fba65535077 # < make -s -j 80 ARCH=arm64 O=/kisskb/build/gustavoars_arm64-allmodconfig_arm64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux- allmodconfig # < make -s -j 80 ARCH=arm64 O=/kisskb/build/gustavoars_arm64-allmodconfig_arm64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux- help # make -s -j 80 ARCH=arm64 O=/kisskb/build/gustavoars_arm64-allmodconfig_arm64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux- olddefconfig # make -s -j 80 ARCH=arm64 O=/kisskb/build/gustavoars_arm64-allmodconfig_arm64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux- /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/scripts/dtc/include-prefixes/arm/bcm2835-rpi.dtsi:18.4-15: Warning (dma_ranges_format): /soc/firmware:dma-ranges: empty "dma-ranges" property but its #address-cells (2) differs from /soc (1) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/arch/arm64/boot/dts/broadcom/stingray/stingray-usb.dtsi:7.3-14: Warning (dma_ranges_format): /usb:dma-ranges: empty "dma-ranges" property but its #address-cells (1) differs from / (2) /kisskb/src/arch/arm64/boot/dts/broadcom/stingray/stingray-usb.dtsi:7.3-14: Warning (dma_ranges_format): /usb:dma-ranges: empty "dma-ranges" property but its #size-cells (1) differs from / (2) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/scripts/dtc/include-prefixes/arm/bcm2835-rpi.dtsi:18.4-15: Warning (dma_ranges_format): /soc/firmware:dma-ranges: empty "dma-ranges" property but its #address-cells (2) differs from /soc (1) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/scripts/dtc/include-prefixes/arm/bcm2835-rpi.dtsi:18.4-15: Warning (dma_ranges_format): /soc/firmware:dma-ranges: empty "dma-ranges" property but its #address-cells (2) differs from /soc (1) /kisskb/src/arch/arm64/boot/dts/broadcom/stingray/stingray-usb.dtsi:7.3-14: Warning (dma_ranges_format): /usb:dma-ranges: empty "dma-ranges" property but its #address-cells (1) differs from / (2) /kisskb/src/arch/arm64/boot/dts/broadcom/stingray/stingray-usb.dtsi:7.3-14: Warning (dma_ranges_format): /usb:dma-ranges: empty "dma-ranges" property but its #size-cells (1) differs from / (2) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/scripts/dtc/include-prefixes/arm/bcm2835-rpi.dtsi:18.4-15: Warning (dma_ranges_format): /soc/firmware:dma-ranges: empty "dma-ranges" property but its #address-cells (2) differs from /soc (1) /kisskb/src/scripts/dtc/include-prefixes/arm/bcm2835-rpi.dtsi:18.4-15: Warning (dma_ranges_format): /soc/firmware:dma-ranges: empty "dma-ranges" property but its #address-cells (2) differs from /soc (1) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/arch/arm64/boot/dts/broadcom/stingray/stingray-usb.dtsi:7.3-14: Warning (dma_ranges_format): /usb:dma-ranges: empty "dma-ranges" property but its #address-cells (1) differs from / (2) /kisskb/src/arch/arm64/boot/dts/broadcom/stingray/stingray-usb.dtsi:7.3-14: Warning (dma_ranges_format): /usb:dma-ranges: empty "dma-ranges" property but its #size-cells (1) differs from / (2) /kisskb/src/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi:1086.4-52: Warning (dma_ranges_format): /soc/dram-controller@1c62000:dma-ranges: "dma-ranges" property has invalid length (12 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 1) /kisskb/src/arch/arm64/boot/dts/qcom/ipq6018.dtsi:127.3-14: Warning (dma_ranges_format): /soc:dma-ranges: empty "dma-ranges" property but its #address-cells (1) differs from / (2) /kisskb/src/arch/arm64/boot/dts/qcom/ipq6018.dtsi:127.3-14: Warning (dma_ranges_format): /soc:dma-ranges: empty "dma-ranges" property but its #size-cells (1) differs from / (2) Completed OK # rm -rf /kisskb/build/gustavoars_arm64-allmodconfig_arm64-gcc8 # Build took: 0:24:26.254162