From: Thorsten Blum <thorsten.blum@linux.dev>
Date: Fri, 17 Apr 2026 09:42:40 +0000 (+0200)
Subject: dcache: use kmalloc_flex() in __d_alloc
X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=0447533faeeefc02c2979abf46c4dcbbbe6d9871;p=thirdparty%2Fkernel%2Flinux.git

dcache: use kmalloc_flex() in __d_alloc

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>
Link: https://patch.msgid.link/20260417094238.551114-3-thorsten.blum@linux.dev
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jori Koolstra <jkoolstra@xs4all.nl>
Signed-off-by: Christian Brauner <brauner@kernel.org>
---

diff --git a/fs/dcache.c b/fs/dcache.c
index 2c61aeea41f45..8ffc4ef79bbab 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -1820,10 +1820,10 @@ 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;