From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A8D4B146A90; Thu, 11 Apr 2024 10:21:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712830891; cv=none; b=QxDp9X8ae7GOyZm9o4arhJIhSjjSqR4BNFTv50otjHvnjj7D/VGomOKLmLb32+M51dlk8mlnUVffhAmjcRXTKuUDObf4Bkvb3crETLMAvEXU/vI8UQTcrJ/FgbZ9T8EsqKCrdtaUkCye3r1/xe6U6FV9YVyYy9NVlXVu4Ez7qNI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712830891; c=relaxed/simple; bh=A8yYUqrenb/ctc03J5kXKv2bcaZ6AiOMZ0Hb7VJxAOw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=HBpsBNPkPjXJPv+iNkAeBpMDg/leaih3CDnZUc16vTQROnd/VGKjW94EQezmvLdm2x0yoLXmgjxPB71f95iTvf/Cfw3g1BAMWKIG8hfWb4T61sqrqD3Bs+myGZ42DD8DC4ZkprQ2wV2QIQZfgDlJ897h2HnGulQTO/BF4KvUYEs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=XlD5G9EC; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="XlD5G9EC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2D3C0C433C7; Thu, 11 Apr 2024 10:21:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712830891; bh=A8yYUqrenb/ctc03J5kXKv2bcaZ6AiOMZ0Hb7VJxAOw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XlD5G9EC26BHD6o0B1D2SOkLvcOk8Cij2h85qS38waQ/J/weNMEyA675zQBxNh7m/ LDdcka+S66ujY0rmpDkpe87SGMcM+KEC3+zimGS/IOm35HUsJIlKiU5pqy1UsULwDb bUx6TkP9dRUlYIq7Y+Mud0VE4AzvlSa5WoqJDq0k= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Max Filippov , Kees Cook Subject: [PATCH 5.4 114/215] exec: Fix NOMMU linux_binprm::exec in transfer_args_to_stack() Date: Thu, 11 Apr 2024 11:55:23 +0200 Message-ID: <20240411095428.333138002@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240411095424.875421572@linuxfoundation.org> References: <20240411095424.875421572@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Max Filippov commit 2aea94ac14d1e0a8ae9e34febebe208213ba72f7 upstream. In NOMMU kernel the value of linux_binprm::p is the offset inside the temporary program arguments array maintained in separate pages in the linux_binprm::page. linux_binprm::exec being a copy of linux_binprm::p thus must be adjusted when that array is copied to the user stack. Without that adjustment the value passed by the NOMMU kernel to the ELF program in the AT_EXECFN entry of the aux array doesn't make any sense and it may break programs that try to access memory pointed to by that entry. Adjust linux_binprm::exec before the successful return from the transfer_args_to_stack(). Cc: Fixes: b6a2fea39318 ("mm: variable length argument support") Fixes: 5edc2a5123a7 ("binfmt_elf_fdpic: wire up AT_EXECFD, AT_EXECFN, AT_SECURE") Signed-off-by: Max Filippov Link: https://lore.kernel.org/r/20240320182607.1472887-1-jcmvbkbc@gmail.com Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman --- fs/exec.c | 1 + 1 file changed, 1 insertion(+) --- a/fs/exec.c +++ b/fs/exec.c @@ -836,6 +836,7 @@ int transfer_args_to_stack(struct linux_ goto out; } + bprm->exec += *sp_location - MAX_ARG_PAGES * PAGE_SIZE; *sp_location = sp; out: