Re: [PATCH] ext4: Annotate struct ext4_xattr_inode_array with __counted_by()

[yebin (H)]

On 2024/7/29 19:04, Thorsten Blum wrote:
Add the __counted_by compiler attribute to the flexible array member
inodes to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
CONFIG_FORTIFY_SOURCE.

Remove the now obsolete comment on the count field.

Signed-off-by: Thorsten Blum <thorsten.b...@toblux.com>
---
  fs/ext4/xattr.h | 4 ++--
  1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/xattr.h b/fs/ext4/xattr.h
index bd97c4aa8177..e14fb19dc912 100644
--- a/fs/ext4/xattr.h
+++ b/fs/ext4/xattr.h
@@ -130,8 +130,8 @@ struct ext4_xattr_ibody_find {
  };
  
  struct ext4_xattr_inode_array {
-       unsigned int count;             /* # of used items in the array */
-       struct inode *inodes[];
+       unsigned int count;
As the comment says, 'count' is the number of items in the array that 
have been used,
not the total number of items in the array. So I think this check was 
added incorrectly.
+       struct inode *inodes[] __counted_by(count);
  };
  
  extern const struct xattr_handler ext4_xattr_user_handler;