This is a note to let you know that I've just added the patch titled f2fs: compress: don't allow unaligned truncation on released compress inode to the 6.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: f2fs-compress-don-t-allow-unaligned-truncation-on-re.patch and it can be found in the queue-6.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 0b1ca78528f08924120089818ea783e7abbd0fc6 Author: Chao Yu <chao@xxxxxxxxxx> Date: Fri May 10 11:33:39 2024 +0800 f2fs: compress: don't allow unaligned truncation on released compress inode [ Upstream commit 29ed2b5dd521ce7c5d8466cd70bf0cc9d07afeee ] f2fs image may be corrupted after below testcase: - mkfs.f2fs -O extra_attr,compression -f /dev/vdb - mount /dev/vdb /mnt/f2fs - touch /mnt/f2fs/file - f2fs_io setflags compression /mnt/f2fs/file - dd if=/dev/zero of=/mnt/f2fs/file bs=4k count=4 - f2fs_io release_cblocks /mnt/f2fs/file - truncate -s 8192 /mnt/f2fs/file - umount /mnt/f2fs - fsck.f2fs /dev/vdb [ASSERT] (fsck_chk_inode_blk:1256) --> ino: 0x5 has i_blocks: 0x00000002, but has 0x3 blocks [FSCK] valid_block_count matching with CP [Fail] [0x4, 0x5] [FSCK] other corrupted bugs [Fail] The reason is: partial truncation assume compressed inode has reserved blocks, after partial truncation, valid block count may change w/o .i_blocks and .total_valid_block_count update, result in corruption. This patch only allow cluster size aligned truncation on released compress inode for fixing. Fixes: c61404153eb6 ("f2fs: introduce FI_COMPRESS_RELEASED instead of using IMMUTABLE bit") Signed-off-by: Chao Yu <chao@xxxxxxxxxx> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 0971dc22810f7..8d3a854f8b0e7 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -935,9 +935,14 @@ int f2fs_setattr(struct mnt_idmap *idmap, struct dentry *dentry, ATTR_GID | ATTR_TIMES_SET)))) return -EPERM; - if ((attr->ia_valid & ATTR_SIZE) && - !f2fs_is_compress_backend_ready(inode)) - return -EOPNOTSUPP; + if ((attr->ia_valid & ATTR_SIZE)) { + if (!f2fs_is_compress_backend_ready(inode)) + return -EOPNOTSUPP; + if (is_inode_flag_set(inode, FI_COMPRESS_RELEASED) && + !IS_ALIGNED(attr->ia_size, + F2FS_BLK_TO_BYTES(F2FS_I(inode)->i_cluster_size))) + return -EINVAL; + } err = setattr_prepare(idmap, dentry, attr); if (err)