# git rev-parse -q --verify 467f8165a2b0e6accf3d0dd9c8089b1dbde29f7f^{commit} 467f8165a2b0e6accf3d0dd9c8089b1dbde29f7f already have revision, skipping fetch # git checkout -q -f -B kisskb 467f8165a2b0e6accf3d0dd9c8089b1dbde29f7f # git clean -qxdf # < git log -1 # commit 467f8165a2b0e6accf3d0dd9c8089b1dbde29f7f # Merge: 3872f516aab3 6abc20f8f879 # Author: Linus Torvalds # Date: Sat Dec 19 13:03:12 2020 -0800 # # Merge tag 'close-range-cloexec-unshare-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux # # Pull close_range fix from Christian Brauner: # "syzbot reported a bug when asking close_range() to unshare the file # descriptor table and making all fds close-on-exec. # # If CLOSE_RANGE_UNSHARE the caller will receive a private file # descriptor table in case their file descriptor table is currently # shared before operating on the requested file descriptor range. # # For the case where the caller has requested all file descriptors to be # actually closed via e.g. close_range(3, ~0U, CLOSE_RANGE_UNSHARE) the # kernel knows that the caller does not need any of the file descriptors # anymore and will optimize the close operation by only copying all # files in the range from 0 to 3 and no others. # # However, if the caller requested CLOSE_RANGE_CLOEXEC together with # CLOSE_RANGE_UNSHARE the caller wants to still make use of the file # descriptors so the kernel needs to copy all of them and can't # optimize. # # The original patch didn't account for this and thus could cause oopses # as evidenced by the syzbot report because it assumed that all fds had # been copied. Fix this by handling the CLOSE_RANGE_CLOEXEC case and # copying all fds if the two flags are specified together. # # This should've been caught in the selftests but the original patch # didn't cover this case and I didn't catch it during review. So in # addition to the bugfix I'm also adding selftests. They will reliably # reproduce the bug on a non-fixed kernel and allows us to catch # regressions and verify correct behavior. # # Note, the kernel selftest tree contained a bunch of changes that made # the original selftest fail to compile so there are small fixups in # here make them compile without warnings" # # * tag 'close-range-cloexec-unshare-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: # selftests/core: add regression test for CLOSE_RANGE_UNSHARE | CLOSE_RANGE_CLOEXEC # selftests/core: add test for CLOSE_RANGE_UNSHARE | CLOSE_RANGE_CLOEXEC # selftests/core: handle missing syscall number for close_range # selftests/core: fix close_range_test build after XFAIL removal # close_range: unshare all fds for CLOSE_RANGE_UNSHARE | CLOSE_RANGE_CLOEXEC # < /opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-gcc --version # < /opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-ld --version # < git log --format=%s --max-count=1 467f8165a2b0e6accf3d0dd9c8089b1dbde29f7f # < make -s -j 32 ARCH=arm64 O=/kisskb/build/linus-rand_arm64-randconfig_arm64-gcc5.4 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux- randconfig KCONFIG_SEED=0xCD334137 # Added to kconfig CONFIG_PREVENT_FIRMWARE_BUILD=y # < make -s -j 32 ARCH=arm64 O=/kisskb/build/linus-rand_arm64-randconfig_arm64-gcc5.4 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux- help # make -s -j 32 ARCH=arm64 O=/kisskb/build/linus-rand_arm64-randconfig_arm64-gcc5.4 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux- olddefconfig .config:4913:warning: override: reassigning to symbol PREVENT_FIRMWARE_BUILD # make -s -j 32 ARCH=arm64 O=/kisskb/build/linus-rand_arm64-randconfig_arm64-gcc5.4 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux- arch/arm64/Makefile:25: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum arch/arm64/Makefile:25: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum Completed OK # rm -rf /kisskb/build/linus-rand_arm64-randconfig_arm64-gcc5.4 # Build took: 0:03:48.887824