From patchwork Sat May 9 19:42:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11538515 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 974841668 for ; Sat, 9 May 2020 19:46:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 84989214D8 for ; Sat, 9 May 2020 19:46:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728098AbgEITqX (ORCPT ); Sat, 9 May 2020 15:46:23 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:53778 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727938AbgEITqW (ORCPT ); Sat, 9 May 2020 15:46:22 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out03.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jXVQT-00010n-JQ; Sat, 09 May 2020 13:46:21 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jXVQS-0001AK-Ni; Sat, 09 May 2020 13:46:21 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: Linus Torvalds , Oleg Nesterov , Jann Horn , Kees Cook , Greg Ungerer , Rob Landley , Bernd Edlinger , , Al Viro , Alexey Dobriyan , Andrew Morton , Casey Schaufler , linux-security-module@vger.kernel.org, James Morris , "Serge E. Hallyn" , Andy Lutomirski References: <87h7wujhmz.fsf@x220.int.ebiederm.org> <87sgga6ze4.fsf@x220.int.ebiederm.org> <87v9l4zyla.fsf_-_@x220.int.ebiederm.org> Date: Sat, 09 May 2020 14:42:52 -0500 In-Reply-To: <87v9l4zyla.fsf_-_@x220.int.ebiederm.org> (Eric W. Biederman's message of "Sat, 09 May 2020 14:40:17 -0500") Message-ID: <873688zygz.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jXVQS-0001AK-Ni;;;mid=<873688zygz.fsf_-_@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1+OrFdAy5/7YXr8d4/LPpD0UxlU62AvuFQ= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa07.xmission.com X-Spam-Level: ** X-Spam-Status: No, score=2.0 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TooManySym_01,XMNoVowels,XMSubLong autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 1.5 XMNoVowels Alpha-numberic number with no vowels * 0.7 XMSubLong Long Subject * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa07 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: ; sa07 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: **; X-Spam-Relay-Country: X-Spam-Timing: total 467 ms - load_scoreonly_sql: 0.03 (0.0%), signal_user_changed: 11 (2.3%), b_tie_ro: 9 (2.0%), parse: 0.95 (0.2%), extract_message_metadata: 12 (2.5%), get_uri_detail_list: 2.2 (0.5%), tests_pri_-1000: 13 (2.9%), tests_pri_-950: 1.23 (0.3%), tests_pri_-900: 1.01 (0.2%), tests_pri_-90: 65 (14.0%), check_bayes: 64 (13.7%), b_tokenize: 11 (2.3%), b_tok_get_all: 9 (1.8%), b_comp_prob: 2.4 (0.5%), b_tok_touch_all: 39 (8.4%), b_finish: 0.78 (0.2%), tests_pri_0: 346 (74.1%), check_dkim_signature: 0.55 (0.1%), check_dkim_adsp: 2.3 (0.5%), poll_dns_idle: 0.67 (0.1%), tests_pri_10: 2.4 (0.5%), tests_pri_500: 12 (2.5%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH 5/5] exec: Move the call of prepare_binprm into search_binary_handler X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: The code in prepare_binary_handler needs to be run every time search_binary_handler is called so move the call into search_binary_handler itself to make the code simpler and easier to understand. Signed-off-by: "Eric W. Biederman" Reviewed-by: Kees Cook --- arch/alpha/kernel/binfmt_loader.c | 3 --- fs/binfmt_em86.c | 5 ----- fs/binfmt_misc.c | 4 ---- fs/binfmt_script.c | 3 --- fs/exec.c | 12 +++++------- include/linux/binfmts.h | 1 - 6 files changed, 5 insertions(+), 23 deletions(-) diff --git a/arch/alpha/kernel/binfmt_loader.c b/arch/alpha/kernel/binfmt_loader.c index a90c8b1d5498..ec7b26e4b81a 100644 --- a/arch/alpha/kernel/binfmt_loader.c +++ b/arch/alpha/kernel/binfmt_loader.c @@ -35,9 +35,6 @@ static int load_binary(struct linux_binprm *bprm) bprm->file = file; bprm->loader = loader; - retval = prepare_binprm(bprm); - if (retval < 0) - return retval; return 1; /* Search for the interpreter */ } diff --git a/fs/binfmt_em86.c b/fs/binfmt_em86.c index a9b9ac7f9bb0..2726bfb832b2 100644 --- a/fs/binfmt_em86.c +++ b/fs/binfmt_em86.c @@ -90,11 +90,6 @@ static int load_em86(struct linux_binprm *bprm) return PTR_ERR(file); bprm->file = file; - - retval = prepare_binprm(bprm); - if (retval < 0) - return retval; - return 1; /* Search for the interpreter */ } diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c index 16bfafd2671d..6b5e67eed65e 100644 --- a/fs/binfmt_misc.c +++ b/fs/binfmt_misc.c @@ -221,10 +221,6 @@ static int load_misc_binary(struct linux_binprm *bprm) if (fmt->flags & MISC_FMT_CREDENTIALS) bprm->preserve_creds = 1; - retval = prepare_binprm(bprm); - if (retval < 0) - goto error; - retval = 1; /* Search for the interpreter */ ret: dput(fmt->dentry); diff --git a/fs/binfmt_script.c b/fs/binfmt_script.c index 76a05696d376..ed4607c7095e 100644 --- a/fs/binfmt_script.c +++ b/fs/binfmt_script.c @@ -143,9 +143,6 @@ static int load_script(struct linux_binprm *bprm) return PTR_ERR(file); bprm->file = file; - retval = prepare_binprm(bprm); - if (retval < 0) - return retval; return 1; /* Search for the interpreter */ } diff --git a/fs/exec.c b/fs/exec.c index 01dbeb025c46..206f18120073 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1628,7 +1628,7 @@ static void bprm_fill_uid(struct linux_binprm *bprm) * * This may be called multiple times for binary chains (scripts for example). */ -int prepare_binprm(struct linux_binprm *bprm) +static int prepare_binprm(struct linux_binprm *bprm) { loff_t pos = 0; @@ -1647,8 +1647,6 @@ int prepare_binprm(struct linux_binprm *bprm) return kernel_read(bprm->file, bprm->buf, BINPRM_BUF_SIZE, &pos); } -EXPORT_SYMBOL(prepare_binprm); - /* * Arguments are '\0' separated strings found at the location bprm->p * points to; chop off the first by relocating brpm->p to right after @@ -1700,6 +1698,10 @@ static int search_binary_handler(struct linux_binprm *bprm) struct linux_binfmt *fmt; int retval; + retval = prepare_binprm(bprm); + if (retval < 0) + return retval; + retval = security_bprm_check(bprm); if (retval) return retval; @@ -1859,10 +1861,6 @@ static int __do_execve_file(int fd, struct filename *filename, if (retval) goto out; - retval = prepare_binprm(bprm); - if (retval < 0) - goto out; - retval = copy_strings_kernel(1, &bprm->filename, bprm); if (retval < 0) goto out; diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h index cb016f001e7a..0748afca40cb 100644 --- a/include/linux/binfmts.h +++ b/include/linux/binfmts.h @@ -117,7 +117,6 @@ static inline void insert_binfmt(struct linux_binfmt *fmt) extern void unregister_binfmt(struct linux_binfmt *); -extern int prepare_binprm(struct linux_binprm *); extern int __must_check remove_arg_zero(struct linux_binprm *); extern int begin_new_exec(struct linux_binprm * bprm); extern void setup_new_exec(struct linux_binprm * bprm);