From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B715CC33CB3 for ; Wed, 15 Jan 2020 12:19:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E4F1207FF for ; Wed, 15 Jan 2020 12:19:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731727AbgAOMTc (ORCPT ); Wed, 15 Jan 2020 07:19:32 -0500 Received: from mout.kundenserver.de ([217.72.192.74]:44145 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731258AbgAOMTb (ORCPT ); Wed, 15 Jan 2020 07:19:31 -0500 Received: from [192.168.100.1] ([78.238.229.36]) by mrelayeu.kundenserver.de (mreue107 [213.165.67.119]) with ESMTPSA (Nemesis) id 1MHndY-1iuVTR2UBa-00Ey0q; Wed, 15 Jan 2020 13:19:23 +0100 Subject: Re: [RFC v2] binfmt_misc: pass binfmt_misc flags to the interpreter From: Laurent Vivier To: linux-kernel@vger.kernel.org, Alexander Viro Cc: linux-fsdevel@vger.kernel.org, James Bottomley References: <20191122150830.15855-1-laurent@vivier.eu> Autocrypt: addr=laurent@vivier.eu; prefer-encrypt=mutual; keydata= mQINBFYFJhkBEAC2me7w2+RizYOKZM+vZCx69GTewOwqzHrrHSG07MUAxJ6AY29/+HYf6EY2 WoeuLWDmXE7A3oJoIsRecD6BXHTb0OYS20lS608anr3B0xn5g0BX7es9Mw+hV/pL+63EOCVm SUVTEQwbGQN62guOKnJJJfphbbv82glIC/Ei4Ky8BwZkUuXd7d5NFJKC9/GDrbWdj75cDNQx UZ9XXbXEKY9MHX83Uy7JFoiFDMOVHn55HnncflUncO0zDzY7CxFeQFwYRbsCXOUL9yBtqLer Ky8/yjBskIlNrp0uQSt9LMoMsdSjYLYhvk1StsNPg74+s4u0Q6z45+l8RAsgLw5OLtTa+ePM JyS7OIGNYxAX6eZk1+91a6tnqfyPcMbduxyBaYXn94HUG162BeuyBkbNoIDkB7pCByed1A7q q9/FbuTDwgVGVLYthYSfTtN0Y60OgNkWCMtFwKxRaXt1WFA5ceqinN/XkgA+vf2Ch72zBkJL RBIhfOPFv5f2Hkkj0MvsUXpOWaOjatiu0fpPo6Hw14UEpywke1zN4NKubApQOlNKZZC4hu6/ 8pv2t4HRi7s0K88jQYBRPObjrN5+owtI51xMaYzvPitHQ2053LmgsOdN9EKOqZeHAYG2SmRW LOxYWKX14YkZI5j/TXfKlTpwSMvXho+efN4kgFvFmP6WT+tPnwARAQABtCJMYXVyZW50IFZp dmllciA8bGF1cmVudEB2aXZpZXIuZXU+iQI4BBMBAgAiBQJWBTDeAhsDBgsJCAcDAgYVCAIJ CgsEFgIDAQIeAQIXgAAKCRDzDDi9Py++PCEdD/oD8LD5UWxhQrMQCsUgLlXCSM7sxGLkwmmF ozqSSljEGRhffxZvO35wMFcdX9Z0QOabVoFTKrT04YmvbjsErh/dP5zeM/4EhUByeOS7s6Yl HubMXVQTkak9Wa9Eq6irYC6L41QNzz/oTwNEqL1weV1+XC3TNnht9B76lIaELyrJvRfgsp9M rE+PzGPo5h7QHWdL/Cmu8yOtPLa8Y6l/ywEJ040IoiAUfzRoaJs2csMXf0eU6gVBhCJ4bs91 jtWTXhkzdl4tdV+NOwj3j0ukPy+RjqeL2Ej+bomnPTOW8nAZ32dapmu7Fj7VApuQO/BSIHyO NkowMMjB46yohEepJaJZkcgseaus0x960c4ua/SUm/Nm6vioRsxyUmWd2nG0m089pp8LPopq WfAk1l4GciiMepp1Cxn7cnn1kmG6fhzedXZ/8FzsKjvx/aVeZwoEmucA42uGJ3Vk9TiVdZes lqMITkHqDIpHjC79xzlWkXOsDbA2UY/P18AtgJEZQPXbcrRBtdSifCuXdDfHvI+3exIdTpvj BfbgZAar8x+lcsQBugvktlQWPfAXZu4Shobi3/mDYMEDOE92dnNRD2ChNXg2IuvAL4OW40wh gXlkHC1ZgToNGoYVvGcZFug1NI+vCeCFchX+L3bXyLMg3rAfWMFPAZLzn42plIDMsBs+x2yP +bkCDQRWBSYZARAAvFJBFuX9A6eayxUPFaEczlMbGXugs0mazbOYGlyaWsiyfyc3PStHLFPj rSTaeJpPCjBJErwpZUN4BbpkBpaJiMuVO6egrC8Xy8/cnJakHPR2JPEvmj7Gm/L9DphTcE15 92rxXLesWzGBbuYxKsj8LEnrrvLyi3kNW6B5LY3Id+ZmU8YTQ2zLuGV5tLiWKKxc6s3eMXNq wrJTCzdVd6ThXrmUfAHbcFXOycUyf9vD+s+WKpcZzCXwKgm7x1LKsJx3UhuzT8ier1L363RW ZaJBZ9CTPiu8R5NCSn9V+BnrP3wlFbtLqXp6imGhazT9nJF86b5BVKpF8Vl3F0/Y+UZ4gUwL d9cmDKBcmQU/JaRUSWvvolNu1IewZZu3rFSVgcpdaj7F/1aC0t5vLdx9KQRyEAKvEOtCmP4m 38kU/6r33t3JuTJnkigda4+Sfu5kYGsogeYG6dNyjX5wpK5GJIJikEhdkwcLM+BUOOTi+I9u tX03BGSZo7FW/J7S9y0l5a8nooDs2gBRGmUgYKqQJHCDQyYut+hmcr+BGpUn9/pp2FTWijrP inb/Pc96YDQLQA1q2AeAFv3Rx3XoBTGl0RCY4KZ02c0kX/dm3eKfMX40XMegzlXCrqtzUk+N 8LeipEsnOoAQcEONAWWo1HcgUIgCjhJhBEF0AcELOQzitbJGG5UAEQEAAYkCHwQYAQIACQUC VgUmGQIbDAAKCRDzDDi9Py++PCD3D/9VCtydWDdOyMTJvEMRQGbx0GacqpydMEWbE3kUW0ha US5jz5gyJZHKR3wuf1En/3z+CEAEfP1M3xNGjZvpaKZXrgWaVWfXtGLoWAVTfE231NMQKGoB w2Dzx5ivIqxikXB6AanBSVpRpoaHWb06tPNxDL6SVV9lZpUn03DSR6gZEZvyPheNWkvz7bE6 FcqszV/PNvwm0C5Ju7NlJA8PBAQjkIorGnvN/vonbVh5GsRbhYPOc/JVwNNr63P76rZL8Gk/ hb3xtcIEi5CCzab45+URG/lzc6OV2nTj9Lg0SNcRhFZ2ILE3txrmI+aXmAu26+EkxLLfqCVT ohb2SffQha5KgGlOSBXustQSGH0yzzZVZb+HZPEvx6d/HjQ+t9sO1bCpEgPdZjyMuuMp9N1H ctbwGdQM2Qb5zgXO+8ZSzwC+6rHHIdtcB8PH2j+Nd88dVGYlWFKZ36ELeZxD7iJflsE8E8yg OpKgu3nD0ahBDqANU/ZmNNarBJEwvM2vfusmNnWm3QMIwxNuJghRyuFfx694Im1js0ZY3LEU JGSHFG4ZynA+ZFUPA6Xf0wHeJOxGKCGIyeKORsteIqgnkINW9fnKJw2pgk8qHkwVc3Vu+wGS ZiJK0xFusPQehjWTHn9WjMG1zvQ5TQQHxau/2FkP45+nRPco6vVFQe8JmgtRF8WFJA== Message-ID: <2a464b33-0b1d-ff35-5aab-77019a072593@vivier.eu> Date: Wed, 15 Jan 2020 13:19:16 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.3.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: fr Content-Transfer-Encoding: 8bit X-Provags-ID: V03:K1:rzRuXGOLOhVdHCUnIp0jlhvpy9y2n1TLQC1eG4D3zAmByzWNm32 tcTt1JPbq79q/gG3KDTeoZ3w/CIF9x9jJG4bXbhvAEXJ3dQHp5aJXqp5hV02PWu2nOywu1P onzgiXaBgwEzA+3j9cwuJWa0snLoUeEhpmUrTfPfHvxxl51C2xSydnJU00qvc0vgTBfTtX8 v0ymUvbqYMUo8TVuJbpCQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:ZLwRR0oePp0=:rTdyxLthyF8D5mpHxzzxUy srzGsb2RIkLY0zDPKBN/yJFHbzvuWwc9m+q0g4XP60gvakStlFiZ8UAXN4xEqajvyOzM4ZRiU 2+nxo+sZBt1/wbxzSO9uL8jIDPh35irVvqhjWMex/NCnIXAhPyIrMxfoC/BzFEhtXKLlof4Km 57DAApi+zkpznlb/W7g2BE9Odo4eIC6oL7ZT7gMAdPrco35kLMzJSkDNWcVIKylyMEXCnw+kJ DhrkKwudB1inKT0bLLbIaE4ir815SI+jBiQMJlN/ym0SP1MSbJciem8G9kGfPeKR2t98T8msC l/1Z/81p+JuXpKjcJEWIdg6i6wpPqiyQZyuP4DQ9R1HOymMw8tn19/3saqRpWDjWj32AQgmrs xC2OEncaj2L2CRr/P2DGQRd5m5FmNhq2f41+OyVAZITpAb9WV3IbEzPl7vGOM8y1PLeYeYngp 9ZuI1EzcXrwbtDFwzxLMvYJJOR0ENBGlB7KD3jFmkHIDTvW9QonO5bk9n3FH7XHInszCo1ktk U3ph6qFMM3H7+AdRSl1oLp2TjHkMC8o+KL+7qZPCt8wJFaV1bybOXsW2CWFsgnyVWvjvlOwUl l/X3wUC3MLI3oDL+oTjtQN7Es0O1ZJ1XXlNx/HKVyAJTi98eGdA/9xyh1jL+yyN2nganwZnRE hGWRvl9fxSx78Tx8LbkC1YPTCv0ArYmskBnRArRpwkjIpJpW6N6UHC2g+hAfm8DTfV+SqXYPp vQAA7mTyOURpOMb7l8S76cXeagaDUYauVZi6w6CVixO/ydfCrYfov//G3/9g+iHlXDFnooMSk K3EwbqU1axD9IMZLrLvCmY102HBrTVIOqw2Eb84t6xAW2RvEO/PaExCPuOksoth3hkMiZJpPc Pf6CjdG0eFVu31d8U4b2xg64gNC/s6Rm0PGzFFJ30= Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Le 07/01/2020 à 15:50, Laurent Vivier a écrit : > Hi, > > this change is simple, easy to read and understand but it is really > needed by user space application interpreter to know the status of the > system configuration. > > Could we have a comment saying if there is a problem or if it is good to > be merged? Anyone? > Thanks, > Laurent > > Le 22/11/2019 à 16:08, Laurent Vivier a écrit : >> It can be useful to the interpreter to know which flags are in use. >> >> For instance, knowing if the preserve-argv[0] is in use would >> allow to skip the pathname argument. >> >> This patch uses an unused auxiliary vector, AT_FLAGS, to pass the >> content of the binfmt flags (special flags: P, F, C, O). >> >> Signed-off-by: Laurent Vivier >> --- >> >> Notes: >> v2: only pass special flags (remove Magic and Enabled flags) >> >> fs/binfmt_elf.c | 2 +- >> fs/binfmt_elf_fdpic.c | 2 +- >> fs/binfmt_misc.c | 6 ++++++ >> include/linux/binfmts.h | 2 +- >> 4 files changed, 9 insertions(+), 3 deletions(-) >> >> diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c >> index c5642bcb6b46..7a34c03e5857 100644 >> --- a/fs/binfmt_elf.c >> +++ b/fs/binfmt_elf.c >> @@ -250,7 +250,7 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec, >> NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr)); >> NEW_AUX_ENT(AT_PHNUM, exec->e_phnum); >> NEW_AUX_ENT(AT_BASE, interp_load_addr); >> - NEW_AUX_ENT(AT_FLAGS, 0); >> + NEW_AUX_ENT(AT_FLAGS, bprm->fmt_flags); >> NEW_AUX_ENT(AT_ENTRY, exec->e_entry); >> NEW_AUX_ENT(AT_UID, from_kuid_munged(cred->user_ns, cred->uid)); >> NEW_AUX_ENT(AT_EUID, from_kuid_munged(cred->user_ns, cred->euid)); >> diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c >> index d86ebd0dcc3d..8fe839be125e 100644 >> --- a/fs/binfmt_elf_fdpic.c >> +++ b/fs/binfmt_elf_fdpic.c >> @@ -647,7 +647,7 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm, >> NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr)); >> NEW_AUX_ENT(AT_PHNUM, exec_params->hdr.e_phnum); >> NEW_AUX_ENT(AT_BASE, interp_params->elfhdr_addr); >> - NEW_AUX_ENT(AT_FLAGS, 0); >> + NEW_AUX_ENT(AT_FLAGS, bprm->fmt_flags); >> NEW_AUX_ENT(AT_ENTRY, exec_params->entry_addr); >> NEW_AUX_ENT(AT_UID, (elf_addr_t) from_kuid_munged(cred->user_ns, cred->uid)); >> NEW_AUX_ENT(AT_EUID, (elf_addr_t) from_kuid_munged(cred->user_ns, cred->euid)); >> diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c >> index cdb45829354d..25a392f23409 100644 >> --- a/fs/binfmt_misc.c >> +++ b/fs/binfmt_misc.c >> @@ -48,6 +48,9 @@ enum {Enabled, Magic}; >> #define MISC_FMT_OPEN_BINARY (1 << 30) >> #define MISC_FMT_CREDENTIALS (1 << 29) >> #define MISC_FMT_OPEN_FILE (1 << 28) >> +#define MISC_FMT_FLAGS_MASK (MISC_FMT_PRESERVE_ARGV0 | MISC_FMT_OPEN_BINARY | \ >> + MISC_FMT_CREDENTIALS | MISC_FMT_OPEN_FILE) >> + >> >> typedef struct { >> struct list_head list; >> @@ -149,6 +152,9 @@ static int load_misc_binary(struct linux_binprm *bprm) >> if (!fmt) >> return retval; >> >> + /* pass special flags to the interpreter */ >> + bprm->fmt_flags = fmt->flags & MISC_FMT_FLAGS_MASK; >> + >> /* Need to be able to load the file after exec */ >> retval = -ENOENT; >> if (bprm->interp_flags & BINPRM_FLAGS_PATH_INACCESSIBLE) >> diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h >> index b40fc633f3be..dae0d0d7b84d 100644 >> --- a/include/linux/binfmts.h >> +++ b/include/linux/binfmts.h >> @@ -60,7 +60,7 @@ struct linux_binprm { >> different for binfmt_{misc,script} */ >> unsigned interp_flags; >> unsigned interp_data; >> - unsigned long loader, exec; >> + unsigned long loader, exec, fmt_flags; >> >> struct rlimit rlim_stack; /* Saved RLIMIT_STACK used during exec. */ >> >> >