# git rev-parse -q --verify 1c24a186398f59c80adb9a967486b65c1423a59d^{commit} 1c24a186398f59c80adb9a967486b65c1423a59d already have revision, skipping fetch # git checkout -q -f -B kisskb 1c24a186398f59c80adb9a967486b65c1423a59d # git clean -qxdf # < git log -1 # commit 1c24a186398f59c80adb9a967486b65c1423a59d # Author: Linus Torvalds # Date: Tue Mar 29 15:06:39 2022 -0700 # # fs: fd tables have to be multiples of BITS_PER_LONG # # This has always been the rule: fdtables have several bitmaps in them, # and as a result they have to be sized properly for bitmaps. We walk # those bitmaps in chunks of 'unsigned long' in serveral cases, but even # when we don't, we use the regular kernel bitops that are defined to work # on arrays of 'unsigned long', not on some byte array. # # Now, the distinction between arrays of bytes and 'unsigned long' # normally only really ends up being noticeable on big-endian systems, but # Fedor Pchelkin and Alexey Khoroshilov reported that copy_fd_bitmaps() # could be called with an argument that wasn't even a multiple of # BITS_PER_BYTE. And then it fails to do the proper copy even on # little-endian machines. # # The bug wasn't in copy_fd_bitmap(), but in sane_fdtable_size(), which # didn't actually sanitize the fdtable size sufficiently, and never made # sure it had the proper BITS_PER_LONG alignment. # # That's partly because the alignment historically came not from having to # explicitly align things, but simply from previous fdtable sizes, and # from count_open_files(), which counts the file descriptors by walking # them one 'unsigned long' word at a time and thus naturally ends up doing # sizing in the proper 'chunks of unsigned long'. # # But with the introduction of close_range(), we now have an external # source of "this is how many files we want to have", and so # sane_fdtable_size() needs to do a better job. # # This also adds that explicit alignment to alloc_fdtable(), although # there it is mainly just for documentation at a source code level. The # arithmetic we do there to pick a reasonable fdtable size already aligns # the result sufficiently. # # In fact,clang notices that the added ALIGN() in that function doesn't # actually do anything, and does not generate any extra code for it. # # It turns out that gcc ends up confusing itself by combining a previous # constant-sized shift operation with the variable-sized shift operations # in roundup_pow_of_two(). And probably due to that doesn't notice that # the ALIGN() is a no-op. But that's a (tiny) gcc misfeature that doesn't # matter. Having the explicit alignment makes sense, and would actually # matter on a 128-bit architecture if we ever go there. # # This also adds big comments above both functions about how fdtable sizes # have to have that BITS_PER_LONG alignment. # # Fixes: 60997c3d45d9 ("close_range: add CLOSE_RANGE_UNSHARE") # Reported-by: Fedor Pchelkin # Reported-by: Alexey Khoroshilov # Link: https://lore.kernel.org/all/20220326114009.1690-1-aissur0002@gmail.com/ # Tested-and-acked-by: Christian Brauner # Signed-off-by: Linus Torvalds # < /opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux-gcc --version # < /opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux-ld --version # < git log --format=%s --max-count=1 1c24a186398f59c80adb9a967486b65c1423a59d # < make -s -j 32 ARCH=um O=/kisskb/build/linus_um-allyesconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 allyesconfig # Added to kconfig CONFIG_STANDALONE=y # Added to kconfig CONFIG_KCOV=n # Added to kconfig CONFIG_GCC_PLUGINS=n # Added to kconfig CONFIG_GCC_PLUGIN_CYC_COMPLEXITY=n # Added to kconfig CONFIG_GCC_PLUGIN_SANCOV=n # Added to kconfig CONFIG_GCC_PLUGIN_LATENT_ENTROPY=n # Added to kconfig CONFIG_GCC_PLUGIN_STRUCTLEAK=n # Added to kconfig CONFIG_GCC_PLUGIN_RANDSTRUCT=n # Added to kconfig CONFIG_UML_NET=n # Added to kconfig CONFIG_UML_NET_ETHERTAP=n # Added to kconfig CONFIG_UML_NET_TUNTAP=n # Added to kconfig CONFIG_UML_NET_SLIP=n # Added to kconfig CONFIG_UML_NET_DAEMON=n # Added to kconfig CONFIG_UML_NET_VDE=n # Added to kconfig CONFIG_UML_NET_MCAST=n # Added to kconfig CONFIG_UML_NET_PCAP=n # Added to kconfig CONFIG_UML_NET_SLIRP=n # Added to kconfig CONFIG_GCOV_KERNEL=n # Added to kconfig CONFIG_DEBUG_INFO_BTF=n # Added to kconfig CONFIG_BPF_PRELOAD=n # < make -s -j 32 ARCH=um O=/kisskb/build/linus_um-allyesconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 help # make -s -j 32 ARCH=um O=/kisskb/build/linus_um-allyesconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 olddefconfig .config:12455:warning: override: reassigning to symbol GCC_PLUGIN_SANCOV .config:12458:warning: override: reassigning to symbol GCC_PLUGIN_RANDSTRUCT .config:12460:warning: override: reassigning to symbol UML_NET_ETHERTAP .config:12462:warning: override: reassigning to symbol UML_NET_SLIP .config:12465:warning: override: reassigning to symbol UML_NET_MCAST .config:12467:warning: override: reassigning to symbol UML_NET_SLIRP # make -s -j 32 ARCH=um O=/kisskb/build/linus_um-allyesconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 In file included from /kisskb/src/arch/x86/um/asm/processor.h:41:0, from /kisskb/src/include/linux/mutex.h:19, from /kisskb/src/include/linux/kernfs.h:11, from /kisskb/src/include/linux/sysfs.h:16, from /kisskb/src/include/linux/kobject.h:20, from /kisskb/src/include/linux/pci.h:35, from /kisskb/src/drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_topology.c:26: /kisskb/src/drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_topology.c: In function 'kfd_cpumask_to_apic_id': /kisskb/src/arch/um/include/asm/processor-generic.h:103:18: error: called object is not a function or function pointer #define cpu_data (&boot_cpu_data) ^ /kisskb/src/drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_topology.c:1557:9: note: in expansion of macro 'cpu_data' return cpu_data(first_cpu_of_numa_node).apicid; ^ /kisskb/src/drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_topology.c:1561:1: error: control reaches end of non-void function [-Werror=return-type] } ^ cc1: all warnings being treated as errors make[5]: *** [/kisskb/src/scripts/Makefile.build:289: drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_topology.o] Error 1 make[5]: *** Waiting for unfinished jobs.... make[4]: *** [/kisskb/src/scripts/Makefile.build:551: drivers/gpu/drm/amd/amdgpu] Error 2 make[4]: *** Waiting for unfinished jobs.... /kisskb/src/drivers/infiniband/sw/rdmavt/qp.c: In function 'rvt_wss_llc_size': /kisskb/src/drivers/infiniband/sw/rdmavt/qp.c:88:22: error: 'struct cpuinfo_um' has no member named 'x86_cache_size' return boot_cpu_data.x86_cache_size; ^ /kisskb/src/drivers/infiniband/sw/rdmavt/qp.c: In function 'cacheless_memcpy': /kisskb/src/drivers/infiniband/sw/rdmavt/qp.c:100:2: error: implicit declaration of function '__copy_user_nocache' [-Werror=implicit-function-declaration] __copy_user_nocache(dst, (void __user *)src, n, 0); ^ /kisskb/src/drivers/infiniband/sw/rdmavt/qp.c: In function 'rvt_wss_llc_size': /kisskb/src/drivers/infiniband/sw/rdmavt/qp.c:89:1: error: control reaches end of non-void function [-Werror=return-type] } ^ cc1: all warnings being treated as errors make[5]: *** [/kisskb/src/scripts/Makefile.build:289: drivers/infiniband/sw/rdmavt/qp.o] Error 1 make[5]: *** Waiting for unfinished jobs.... make[4]: *** [/kisskb/src/scripts/Makefile.build:551: drivers/infiniband/sw/rdmavt] Error 2 make[3]: *** [/kisskb/src/scripts/Makefile.build:551: drivers/infiniband/sw] Error 2 make[3]: *** Waiting for unfinished jobs.... /kisskb/src/drivers/infiniband/hw/qib/qib_wc_x86_64.c: In function 'qib_unordered_wc': /kisskb/src/drivers/infiniband/hw/qib/qib_wc_x86_64.c:149:22: error: 'struct cpuinfo_um' has no member named 'x86_vendor' return boot_cpu_data.x86_vendor != X86_VENDOR_AMD; ^ /kisskb/src/drivers/infiniband/hw/qib/qib_wc_x86_64.c:149:37: error: 'X86_VENDOR_AMD' undeclared (first use in this function) return boot_cpu_data.x86_vendor != X86_VENDOR_AMD; ^ /kisskb/src/drivers/infiniband/hw/qib/qib_wc_x86_64.c:149:37: note: each undeclared identifier is reported only once for each function it appears in /kisskb/src/drivers/infiniband/hw/qib/qib_wc_x86_64.c:150:1: error: control reaches end of non-void function [-Werror=return-type] } ^ cc1: all warnings being treated as errors make[5]: *** [/kisskb/src/scripts/Makefile.build:289: drivers/infiniband/hw/qib/qib_wc_x86_64.o] Error 1 make[5]: *** Waiting for unfinished jobs.... make[4]: *** [/kisskb/src/scripts/Makefile.build:551: drivers/infiniband/hw/qib] Error 2 make[3]: *** [/kisskb/src/scripts/Makefile.build:551: drivers/infiniband/hw] Error 2 make[2]: *** [/kisskb/src/scripts/Makefile.build:551: drivers/infiniband] Error 2 make[2]: *** Waiting for unfinished jobs.... make[3]: *** [/kisskb/src/scripts/Makefile.build:551: drivers/gpu/drm] Error 2 make[2]: *** [/kisskb/src/scripts/Makefile.build:551: drivers/gpu] Error 2 make[1]: *** [/kisskb/src/Makefile:1830: drivers] Error 2 make: *** [Makefile:219: __sub-make] Error 2 Command 'make -s -j 32 ARCH=um O=/kisskb/build/linus_um-allyesconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 ' returned non-zero exit status 2 # rm -rf /kisskb/build/linus_um-allyesconfig_um-x86_64 # Build took: 0:08:50.622633