Add the __counted_by compiler attribute to the flexible array member
name to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
CONFIG_FORTIFY_SOURCE.
Inline and use struct_size() to calculate the number of bytes to
allocate for new_fn and remove the local variable len.
Signed-off-by: Thorsten Blum <thorsten.blum@xxxxxxxxxx>
---
fs/ext4/dir.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index ff4514e4626b..8e7df15bb971 100644
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -408,7 +408,7 @@ struct fname {
__u32 inode;
__u8 name_len;
__u8 file_type;
- char name[];
+ char name[] __counted_by(name_len);
};
/*
@@ -464,14 +464,13 @@ int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
struct rb_node **p, *parent = NULL;
struct fname *fname, *new_fn;
struct dir_private_info *info;
- int len;
info = dir_file->private_data;
p = &info->root.rb_node;
/* Create and allocate the fname structure */
- len = sizeof(struct fname) + ent_name->len + 1;
- new_fn = kzalloc(len, GFP_KERNEL);
+ new_fn = kzalloc(struct_size(new_fn, name, ent_name->len + 1),
+ GFP_KERNEL);
if (!new_fn)
return -ENOMEM;
new_fn->hash = hash;
--
2.46.0
