CVE-2024-33847

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> f2fs: compress: don&amp;#39;t allow unaligned truncation on released compress inode<br /> <br /> f2fs image may be corrupted after below testcase:<br /> - mkfs.f2fs -O extra_attr,compression -f /dev/vdb<br /> - mount /dev/vdb /mnt/f2fs<br /> - touch /mnt/f2fs/file<br /> - f2fs_io setflags compression /mnt/f2fs/file<br /> - dd if=/dev/zero of=/mnt/f2fs/file bs=4k count=4<br /> - f2fs_io release_cblocks /mnt/f2fs/file<br /> - truncate -s 8192 /mnt/f2fs/file<br /> - umount /mnt/f2fs<br /> - fsck.f2fs /dev/vdb<br /> <br /> [ASSERT] (fsck_chk_inode_blk:1256) --&gt; ino: 0x5 has i_blocks: 0x00000002, but has 0x3 blocks<br /> [FSCK] valid_block_count matching with CP [Fail] [0x4, 0x5]<br /> [FSCK] other corrupted bugs [Fail]<br /> <br /> The reason is: partial truncation assume compressed inode has reserved<br /> blocks, after partial truncation, valid block count may change w/o<br /> .i_blocks and .total_valid_block_count update, result in corruption.<br /> <br /> This patch only allow cluster size aligned truncation on released<br /> compress inode for fixing.