Re: [PATCH V2 1/2] erofs: use kmemdup_nul in erofs_fill_symlink

[Gao Xiang]

On 2024/9/2 15:00, Yiyang Wu via Linux-erofs wrote:

Remove open coding in erofs_fill_symlink.

Suggested-by: Al Viro <v...@zeniv.linux.org.uk>
Link: https://lore.kernel.org/all/20240425222847.GN2118490@ZenIV
Signed-off-by: Yiyang Wu <toolm...@tlmp.cc>
---
  fs/erofs/inode.c | 12 +++++-------
  1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index 419432be3223..d051afe39670 100644
--- a/fs/erofs/inode.c
+++ b/fs/erofs/inode.c
@@ -188,22 +188,20 @@ static int erofs_fill_symlink(struct inode *inode, void 
*kaddr,
                return 0;
        }

- lnk = kmalloc(inode->i_size + 1, GFP_KERNEL);

-       if (!lnk)
-               return -ENOMEM;
-
        m_pofs += vi->xattr_isize;
        /* inline symlink data shouldn't cross block boundary */
        if (m_pofs + inode->i_size > bsz) {
-               kfree(lnk);
                erofs_err(inode->i_sb,
                          "inline data cross block boundary @ nid %llu",
                          vi->nid);
                DBG_BUGON(1);
                return -EFSCORRUPTED;
        }
-       memcpy(lnk, kaddr + m_pofs, inode->i_size);
-       lnk[inode->i_size] = '\0';
+
+       lnk = kmemdup_nul(kaddr + m_pofs, inode->i_size, GFP_KERNEL);
+

Unnecessary new line.

Also I wonder if it's possible to just
        inode->i_link = kmemdup_nul(kaddr + m_pofs, inode->i_size, GFP_KERNEL);
        if (!inode->i_link)
                return -ENOMEM;

here, and get rid of variable lnk.

Otherwise it looks good to me.

Thanks,
Gao Xiang

+       if (!lnk)
+               return -ENOMEM;

inode->i_link = lnk;

        inode->i_op = &erofs_fast_symlink_iops;