[PATCH 12/28] ext4: Use i_generation in inode-related metadata checksums
From: Darrick J. Wong <hidden>
Date: 2011-10-08 07:55:02
Also in:
linux-fsdevel, lkml
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
Whenever we are calculating a checksum for a piece of metadata that is associated with an inode, incorporate i_generation into that calculation so that old metadata blocks cannot be re-associated after a delete/create cycle. Signed-off-by: Darrick J. Wong <redacted> --- fs/ext4/ialloc.c | 9 ++++++--- fs/ext4/inode.c | 9 ++++++--- fs/ext4/ioctl.c | 4 ++++ 3 files changed, 16 insertions(+), 6 deletions(-)
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 6e5876a..d4b59e9 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c@@ -1031,11 +1031,14 @@ got: /* Precompute second piece of crc */ if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) { + __u32 crc; struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); __le32 inum = cpu_to_le32(inode->i_ino); - ei->i_uuid_inum_crc = ext4_chksum(sbi, sbi->s_uuid_crc, - (__u8 *)&inum, - sizeof(inum)); + __le32 gen = cpu_to_le32(inode->i_generation); + crc = ext4_chksum(sbi, sbi->s_uuid_crc, (__u8 *)&inum, + sizeof(inum)); + ei->i_uuid_inum_crc = ext4_chksum(sbi, crc, (__u8 *)&gen, + sizeof(gen)); } ext4_clear_state_flags(ei); /* Only relevant on 32-bit archs */
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index b00315d..593f3bf 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c@@ -3492,10 +3492,13 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino) if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); + __u32 crc; __le32 inum = cpu_to_le32(inode->i_ino); - ei->i_uuid_inum_crc = ext4_chksum(sbi, sbi->s_uuid_crc, - (__u8 *)&inum, - sizeof(inum)); + __le32 gen = raw_inode->i_generation; + crc = ext4_chksum(sbi, sbi->s_uuid_crc, (__u8 *)&inum, + sizeof(inum)); + ei->i_uuid_inum_crc = ext4_chksum(sbi, crc, (__u8 *)&gen, + sizeof(gen)); } if (!ext4_inode_csum_verify(inode, raw_inode, ei)) {
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index f18bfe3..fdf0b1e 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c@@ -149,6 +149,10 @@ flags_out: if (!inode_owner_or_capable(inode)) return -EPERM; + if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) + return -ENOTTY; + err = mnt_want_write(filp->f_path.mnt); if (err) return err;