From: Miklos Szeredi <mszeredi@redhat.com>
Date: Tue, 19 Aug 2025 14:44:02 +0000 (+0200)
Subject: fuse: zero initialize inode private data
X-Git-Tag: v6.18-rc1~121^2~13
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3ca1b311181072415b6432a169de765ac2034e5a;p=thirdparty%2Fkernel%2Fstable.git

fuse: zero initialize inode private data

This is slightly tricky, since the VFS uses non-zeroing allocation to
preserve some fields that are left in a consistent state.

Reported-by: Chunsheng Luo <luochunsheng@ustc.edu>
Closes: https://lore.kernel.org/all/20250818083224.229-1-luochunsheng@ustc.edu/
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
---

diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 19fc58cb84dc1..9d26a5bc394d4 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -101,14 +101,11 @@ static struct inode *fuse_alloc_inode(struct super_block *sb)
 	if (!fi)
 		return NULL;
 
-	fi->i_time = 0;
+	/* Initialize private data (i.e. everything except fi->inode) */
+	BUILD_BUG_ON(offsetof(struct fuse_inode, inode) != 0);
+	memset((void *) fi + sizeof(fi->inode), 0, sizeof(*fi) - sizeof(fi->inode));
+
 	fi->inval_mask = ~0;
-	fi->nodeid = 0;
-	fi->nlookup = 0;
-	fi->attr_version = 0;
-	fi->orig_ino = 0;
-	fi->state = 0;
-	fi->submount_lookup = NULL;
 	mutex_init(&fi->mutex);
 	spin_lock_init(&fi->lock);
 	fi->forget = fuse_alloc_forget();