nfs4_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
		  struct iattr *sattr)
{
	struct inode *inode = dentry->d_inode;
	struct rpc_cred *cred = NULL;
	struct nfs4_state *state = NULL;
	int status;

	if (pnfs_ld_layoutret_on_setattr(inode))
		pnfs_return_layout(inode);

	nfs_fattr_init(fattr);
	
	/* Deal with open(O_TRUNC) */
	if (sattr->ia_valid & ATTR_OPEN)
		sattr->ia_valid &= ~(ATTR_MTIME|ATTR_CTIME|ATTR_OPEN);

	/* Optimization: if the end result is no change, don't RPC */
	if ((sattr->ia_valid & ~(ATTR_FILE)) == 0)
		return 0;

	/* Search for an existing open(O_WRITE) file */
	if (sattr->ia_valid & ATTR_FILE) {
		struct nfs_open_context *ctx;

		ctx = nfs_file_open_context(sattr->ia_file);
		if (ctx) {
			cred = ctx->cred;
			state = ctx->state;
		}
	}

	status = nfs4_do_setattr(inode, cred, fattr, sattr, state);
	if (status == 0)
		nfs_setattr_update_inode(inode, sattr);
	return status;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.