[PATCH] dcache: use kmalloc_flex() in __d_alloc

[Thorsten Blum <thorsten.blum@linux.dev>]

Use kmalloc_flex() when allocating a new 'struct external_name' in
__d_alloc() to replace offsetof() and the open-coded size arithmetic,
and to keep the size type-safe.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 fs/dcache.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/dcache.c b/fs/dcache.c
index dbcbd0affb26..4568f9530166 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -1753,10 +1753,10 @@ static struct dentry *__d_alloc(struct super_block *sb, const struct qstr *name)
 		name = &slash_name;
 		dname = dentry->d_shortname.string;
 	} else if (name->len > DNAME_INLINE_LEN-1) {
-		size_t size = offsetof(struct external_name, name[1]);
-		struct external_name *p = kmalloc(size + name->len,
-						  GFP_KERNEL_ACCOUNT |
-						  __GFP_RECLAIMABLE);
+		struct external_name *p;
+
+		p = kmalloc_flex(*p, name, name->len + 1,
+				 GFP_KERNEL_ACCOUNT | __GFP_RECLAIMABLE);
 		if (!p) {
 			kmem_cache_free(dentry_cache, dentry); 
 			return NULL;