From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794063220; b=X1WY0/jrPq/bekQBLebPli1k7H9YpasPkIU8gEzY9al3vm2ZtlCo8fJpNoAYwxYb8d+3 JzFXb9cHdT3vc+TFIDm84Oze3QWrb+lyT/r7Pa+kg23oFVCn7hBZxa693JFwLuKG1qyOw zfsmfE0h65fiNgUJWn/4PHWIVFBsOy8tweZz/668C8w+T8lAfx2Em8uR4kAe/rXV63p1k ViEgD6qBn9R8HuK/eKOnGRxCEBbM1Z4dxGJN53bDASW0zTdPkqsk0Wibx/Boe/geMEWml d5rR8RSk9dcSC9D7GMBDB/xs4ymGwxniawmjf54c+9Kk/g4oLqGSUcyGHaHBv6YIyEg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794063220; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=T+zq/4ApYdhThUsxFv7sIeN0agn28ZB5ZxwksaeVzVE=; b=bn63GAqsdixTuX7Uq7nUCYl6IUFOcnoVufnkO5Ou/BSXFlQfHllmeu5veug+c3KYqpej VHfXzOBZXWHMB8pRVWmYbNLrUPc2hc6nLcuttjFPKIsbhXxsbE6XBk+WzEh7voERepMDs PLXhjIHTbgd00x18cbZowFFuSNxQ4U37ddDFfPNw7Z1iaHDIeQwpJJnytWZDGIAE3Tw/y DzkFYIw44/QmBGLnn5HGCrx8muDr8vcbe1/dncQ/VqwUJUI4Pxdy1b0zG62qEOpPdlDvC vmUM1UoG3MeSoUwpZDVI6ucdtT7Xwr6OvKFlazgF/xbEYtyW3pfZzrA0Z1+14mfrOsA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=LlExhekv; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0A13E606A337; Sat, 7 Nov 2026 14:53:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=LlExhekv Received: by smtp.kernel.org (Postfix) with ESMTPSA id 494881F008A1; Sat, 7 Nov 2026 14:53:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794063219; bh=T+zq/4ApYdhThUsxFv7sIeN0agn28ZB5ZxwksaeVzVE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=LlExhekvN2uU5WJpOnLjqkLiqt1DcPJUyaMVCLXOUZCCU5kxOjSkf5/UFiGsXPGYg McldfT75ayRaCOr5LyPvpkfug8KvkL+RXkrYIJT3O0kmmELZbFq7z2qqFQ8QgSohFl ISu9WWi+30cqZv8SfqokV1NquC3fV/Frf7eXUy64= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Anastasios Papagiannis , Andrew Morton , "Lorenzo Stoakes (ARM)" , "Liam R. Howlett" , Hajime Tazaki , Sasha Levin Subject: [PATCH 6.18 428/869] mm/nommu: reject wrapping ranges in access_remote_vm() Date: Sat, 7 Nov 2026 08:51:50 -0500 Message-ID: <20261107134908.358991482@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134852.069646174@linuxfoundation.org> References: <20261107134852.069646174@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Anastasios Papagiannis [ Upstream commit 51a8de81fd2edbf87d8046e352060329bb216fad ] The NOMMU implementation of access_process_vm() rejects address ranges whose end wraps around, but access_remote_vm() bypasses this check even though both functions delegate to __access_remote_vm(). Move the wraparound check into __access_remote_vm() so it applies to both entry points. This is originally reported in [1]. Link: https://lore.kernel.org/20260909064231.18693-1-tasos.papagiannnis@gmail.com Fixes: f55f199b7d76 ("NOMMU: implement access_remote_vm") Signed-off-by: Anastasios Papagiannis Signed-off-by: Andrew Morton Closes: https://lore.kernel.org/bpf/4ef240a5bea36ff84df9589671367832860795159386a4c8fba546a0fa8b786f@mail.kernel.org/ [1] Reviewed-by: Lorenzo Stoakes (ARM) Cc: Liam R. Howlett Cc: Hajime Tazaki Cc: Signed-off-by: Sasha Levin --- mm/nommu.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/mm/nommu.c b/mm/nommu.c index c3a23b082adb9..d609ecdcf022b 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1644,6 +1644,9 @@ static int __access_remote_vm(struct mm_struct *mm, unsigned long addr, struct vm_area_struct *vma; int write = gup_flags & FOLL_WRITE; + if (addr + len < addr) + return 0; + if (mmap_read_lock_killable(mm)) return 0; @@ -1697,9 +1700,6 @@ int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, in { struct mm_struct *mm; - if (addr + len < addr) - return 0; - mm = get_task_mm(tsk); if (!mm) return 0; -- 2.53.0