From: Zhang Yi yi.zhang@huawei.com
hulk inclusion category: bugfix bugzilla: 174653 https://gitee.com/openeuler/kernel/issues/I4DDEL ---------------------------
In ext4_get_inode_loc(), we may skip IO and get an zero && uptodate inode buffer when the inode monopolize an inode block for performance reason. For most cases, ext4_mark_iloc_dirty() will fill the inode buffer to make it fine, but we could miss this call if something bad happened. Finally, __ext4_get_inode_loc_noinmem() may probably get an empty inode buffer and trigger ext4 error.
For example, if we remove a nonexistent xattr on inode A, ext4_xattr_set_handle() will return ENODATA before invoking ext4_mark_iloc_dirty(), it will left an uptodate but zero buffer. We will get checksum error message in ext4_iget() when getting inode again.
EXT4-fs error (device sda): ext4_lookup:1784: inode #131074: comm cat: iget: checksum invalid
Even worse, if we allocate another inode B at the same inode block, it will corrupt the inode A on disk when write back inode B.
So this patch initialize the inode buffer by filling the in-mem inode contents if we skip read I/O, ensure that the buffer is really uptodate.
Signed-off-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Yang Erkun yangerkun@huawei.com Signed-off-by: Chen Jun chenjun102@huawei.com --- fs/ext4/inode.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-)
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index d76ebbebd455..a054f07a63a6 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4445,12 +4445,12 @@ static int ext4_fill_raw_inode(struct inode *inode, struct ext4_inode *raw_inode
/* * ext4_get_inode_loc returns with an extra refcount against the inode's - * underlying buffer_head on success. If 'in_mem' is true, we have all - * data in memory that is needed to recreate the on-disk version of this - * inode. + * underlying buffer_head on success. If we pass 'inode' and it does not + * have in-inode xattr, we have all inode data in memory that is needed + * to recreate the on-disk version of this inode. */ static int __ext4_get_inode_loc(struct super_block *sb, unsigned long ino, - struct ext4_iloc *iloc, int in_mem, + struct inode *inode, struct ext4_iloc *iloc, ext4_fsblk_t *ret_block) { struct ext4_group_desc *gdp; @@ -4495,7 +4495,7 @@ static int __ext4_get_inode_loc(struct super_block *sb, unsigned long ino, * is the only valid inode in the block, we need not read the * block. */ - if (in_mem) { + if (inode && !ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { struct buffer_head *bitmap_bh; int i, start;
@@ -4523,8 +4523,13 @@ static int __ext4_get_inode_loc(struct super_block *sb, unsigned long ino, } brelse(bitmap_bh); if (i == start + inodes_per_block) { + struct ext4_inode *raw_inode = + (struct ext4_inode *) (bh->b_data + iloc->offset); + /* all other inodes are free, so skip I/O */ memset(bh->b_data, 0, bh->b_size); + if (!ext4_test_inode_state(inode, EXT4_STATE_NEW)) + ext4_fill_raw_inode(inode, raw_inode); set_buffer_uptodate(bh); unlock_buffer(bh); goto has_buffer; @@ -4586,7 +4591,7 @@ static int __ext4_get_inode_loc_noinmem(struct inode *inode, ext4_fsblk_t err_blk; int ret;
- ret = __ext4_get_inode_loc(inode->i_sb, inode->i_ino, iloc, 0, + ret = __ext4_get_inode_loc(inode->i_sb, inode->i_ino, NULL, iloc, &err_blk);
if (ret == -EIO) @@ -4601,9 +4606,8 @@ int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc) ext4_fsblk_t err_blk; int ret;
- /* We have all inode data except xattrs in memory here. */ - ret = __ext4_get_inode_loc(inode->i_sb, inode->i_ino, iloc, - !ext4_test_inode_state(inode, EXT4_STATE_XATTR), &err_blk); + ret = __ext4_get_inode_loc(inode->i_sb, inode->i_ino, inode, iloc, + &err_blk);
if (ret == -EIO) ext4_error_inode_block(inode, err_blk, EIO, @@ -4616,7 +4620,7 @@ int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc) int ext4_get_fc_inode_loc(struct super_block *sb, unsigned long ino, struct ext4_iloc *iloc) { - return __ext4_get_inode_loc(sb, ino, iloc, 0, NULL); + return __ext4_get_inode_loc(sb, ino, NULL, iloc, NULL); }
static bool ext4_should_enable_dax(struct inode *inode)