This change adds a new O_BENEATH flag for openat(2) which restricts the provided path, rejecting (with -EPERM) paths that are not beneath the provided dfd. This change was originally included as part of a larger patchset (https://lkml.org/lkml/2014/7/25/426) for Capsicum support; however, it is potentially useful as an independent change so I've pulled it out separately here. In particular, various folks from Chrome[OS] have indicated an interest in having this functionality -- when combined with a seccomp filter it allows a directory to be accessed by a sandboxed process. Changes since v2: - Move tests into xfstests [Dave Chinner, with thanks for feedback on initial version] - Merge up to v4.0-rc3 & latest man-pages Changes since v1: - Don't needlessly duplicate flags [Al Viro] - Use EPERM rather than EACCES as error code [Paolo Bonzini] - Disallow nd_jump_link for O_BENEATH [Al Viro/Andy Lutomirski] - Add test of a jumped symlink (/proc/self/root) Changes since the version included in the Capsicum v2 patchset: - Add tests of normal symlinks - Fix man-page typo - Update patch to 3.17 Changes from v1 to v2 of Capsicum patchset: - renamed O_BENEATH_ONLY to O_BENEATH [Christoph Hellwig] David Drysdale (1): fs: add O_BENEATH flag to openat(2) arch/alpha/include/uapi/asm/fcntl.h | 1 + arch/parisc/include/uapi/asm/fcntl.h | 1 + arch/sparc/include/uapi/asm/fcntl.h | 1 + fs/fcntl.c | 4 ++-- fs/namei.c | 21 ++++++++++++++++++--- fs/open.c | 4 +++- fs/proc/base.c | 4 +++- fs/proc/namespaces.c | 8 ++++++-- include/linux/namei.h | 3 ++- include/uapi/asm-generic/fcntl.h | 4 ++++ 10 files changed, 41 insertions(+), 10 deletions(-) -- 2.2.0.rc0.207.ga3a616c -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
