"value":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfs: add bounds checking to xlog_recover_process_data\n\nThere is a lack of verification of the space occupied by fixed members\nof xlog_op_header in the xlog_recover_process_data.\n\nWe can create a crafted image to trigger an out of bounds read by\nfollowing these steps:\n 1) Mount an image of xfs, and do some file operations to leave records\n 2) Before umounting, copy the image for subsequent steps to simulate\n abnormal exit. Because umount will ensure that tail_blk and\n head_blk are the same, which will result in the inability to enter\n xlog_recover_process_data\n 3) Write a tool to parse and modify the copied image in step 2\n 4) Make the end of the xlog_op_header entries only 1 byte away from\n xlog_rec_header->h_size\n 5) xlog_rec_header->h_num_logops++\n 6) Modify xlog_rec_header->h_crc\n\nFix:\nAdd a check to make sure there is sufficient space to access fixed members\nof xlog_op_header."
