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 565EC1422C4; Thu, 11 Apr 2024 10:03:52 +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=1712829832; cv=none; b=SelSj7JCeNFdgzNOw1i5a8DMg4Vuquq3T0UGGvszHRmc/JQbi1pAEqKCYYyE/3SwcqRY7MUAPyB/gil7gl8ewxCkasBNPeDE1HY40A1iUTSrRZKMeWlLA+Nl5PPTQhmpyCUtnRqGj3EchzGYDTcTPjWb87TF8UBf0NIaemojUIA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712829832; c=relaxed/simple; bh=gY/ywS09wo5lT7oqShNhI0ZYFETI8848Vyycf0wMdHs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SRLjCQLUTZiJlIP/5i4X+os6NmzE2XvIqvSjF8qlvHRrrdFsMaklATcUfOqyR0yrVeKSRRGQC8AxYCjCuG+/YdJbQNOyC5RKNLgbbL1w1AOG1kfPFJD9UTlfn0BctfRX2qFJkkICzOTdFUvONgHK4X32sUme8KXHjq+X3UO9PpY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=BlMcldXD; 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="BlMcldXD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9BDEDC433F1; Thu, 11 Apr 2024 10:03:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712829832; bh=gY/ywS09wo5lT7oqShNhI0ZYFETI8848Vyycf0wMdHs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BlMcldXDFOfiGMytwVnfq7w3LyTuoK3VUUWoQa+EknHDTuwNIYeQAynRQ1UCW7iPJ JuNN6Wg+anb2/hUWeMQ5jUzjDhtld5MhhCscWamC2IgDfqBfUVSfM26Ll3UU2IKSKo QAVuOZp53tWA7nuLCFd4DNkG9B6eCc2DAuNQNq9Y= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Max Filippov , Kees Cook Subject: [PATCH 4.19 083/175] exec: Fix NOMMU linux_binprm::exec in transfer_args_to_stack() Date: Thu, 11 Apr 2024 11:55:06 +0200 Message-ID: <20240411095422.061715739@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240411095419.532012976@linuxfoundation.org> References: <20240411095419.532012976@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 4.19-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 @@ -823,6 +823,7 @@ int transfer_args_to_stack(struct linux_ goto out; } + bprm->exec += *sp_location - MAX_ARG_PAGES * PAGE_SIZE; *sp_location = sp; out: