On Fri, Feb 07, 2025 at 11:27:42AM +0800, Ye Bin wrote:
> From: Ye Bin <yebin10@xxxxxxxxxx>
>
> Introduce ITAIL helper to get the bound of xattr in inode.
>
> Signed-off-by: Ye Bin <yebin10@xxxxxxxxxx>
> ---
> fs/ext4/xattr.c | 10 +++++-----
> fs/ext4/xattr.h | 3 +++
> 2 files changed, 8 insertions(+), 5 deletions(-)
>
> diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
> index 7647e9f6e190..0e4494863d15 100644
> --- a/fs/ext4/xattr.c
> +++ b/fs/ext4/xattr.c
> @@ -649,7 +649,7 @@ ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name,
> return error;
> raw_inode = ext4_raw_inode(&iloc);
> header = IHDR(inode, raw_inode);
> - end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
> + end = ITAIL(inode, raw_inode);
> error = xattr_check_inode(inode, header, end);
> if (error)
> goto cleanup;
> @@ -793,7 +793,7 @@ ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size)
> return error;
> raw_inode = ext4_raw_inode(&iloc);
> header = IHDR(inode, raw_inode);
> - end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
> + end = ITAIL(inode, raw_inode);
> error = xattr_check_inode(inode, header, end);
> if (error)
> goto cleanup;
> @@ -879,7 +879,7 @@ int ext4_get_inode_usage(struct inode *inode, qsize_t *usage)
> goto out;
> raw_inode = ext4_raw_inode(&iloc);
> header = IHDR(inode, raw_inode);
> - end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
> + end = ITAIL(inode, raw_inode);
> ret = xattr_check_inode(inode, header, end);
> if (ret)
> goto out;
> @@ -2235,7 +2235,7 @@ int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
> header = IHDR(inode, raw_inode);
> is->s.base = is->s.first = IFIRST(header);
> is->s.here = is->s.first;
> - is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
> + is->s.end = ITAIL(inode, raw_inode);
> if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
> error = xattr_check_inode(inode, header, is->s.end);
> if (error)
> @@ -2786,7 +2786,7 @@ int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
> */
>
> base = IFIRST(header);
> - end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
> + end = ITAIL(inode, raw_inode);
> min_offs = end - base;
> total_ino = sizeof(struct ext4_xattr_ibody_header) + sizeof(u32);
>
> diff --git a/fs/ext4/xattr.h b/fs/ext4/xattr.h
> index b25c2d7b5f99..d331bd636480 100644
> --- a/fs/ext4/xattr.h
> +++ b/fs/ext4/xattr.h
> @@ -67,6 +67,9 @@ struct ext4_xattr_entry {
> ((void *)raw_inode + \
> EXT4_GOOD_OLD_INODE_SIZE + \
> EXT4_I(inode)->i_extra_isize))
> +#define ITAIL(inode, raw_inode) \
> + ((void *)raw_inode + \
> + EXT4_SB(inode->i_sb)->s_inode_size)
These are macros, you ought to wrap the arguments in parentheses to
avoid subtle bugs:
#define ITAIL(inode, raw_inode) \
((void *)(raw_inode) + \
EXT4_SB((inode)->i_sb)->s_inode_size)
(or maybe just a static inline helper, but I guess we're passing around
void pointers so meh)
--D
> #define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1))
>
> /*
> --
> 2.34.1
>
>
