3.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dwight Engen <dwight.engen@xxxxxxxxxx> commit 8c567a7fab6e086a0284eee2db82348521e7120c upstream. Check for CAP_SYS_ADMIN since the caller can truncate preallocated blocks from files they do not own nor have write access to. A more fine grained access check was considered: require the caller to specify their own uid/gid and to use inode_permission to check for write, but this would not catch the case of an inode not reachable via path traversal from the callers mount namespace. Add check for read-only filesystem to free eofblocks ioctl. Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx> Reviewed-by: Dave Chinner <dchinner@xxxxxxxxxx> Reviewed-by: Gao feng <gaofeng@xxxxxxxxxxxxxx> Signed-off-by: Dwight Engen <dwight.engen@xxxxxxxxxx> Signed-off-by: Ben Myers <bpm@xxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/xfs/xfs_ioctl.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -1717,6 +1717,12 @@ xfs_file_ioctl( if (mp->m_flags & XFS_MOUNT_RDONLY) return -XFS_ERROR(EROFS); + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (mp->m_flags & XFS_MOUNT_RDONLY) + return -XFS_ERROR(EROFS); + if (copy_from_user(&eofb, arg, sizeof(eofb))) return -XFS_ERROR(EFAULT); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html