From patchwork Mon Jun 15 13:00:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11604923 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 6E7CC1392 for ; Mon, 15 Jun 2020 13:02:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4F31C2078A for ; Mon, 15 Jun 2020 13:02:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="TE4FcjGc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730320AbgFONAs (ORCPT ); Mon, 15 Jun 2020 09:00:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52358 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730262AbgFONAn (ORCPT ); Mon, 15 Jun 2020 09:00:43 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E63DC061A0E; Mon, 15 Jun 2020 06:00:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=R3jVFYS/2IFPi5AjMtMLrTJqX+oMKfiLgBtiR94GLYw=; b=TE4FcjGcDoL2yigYOoInoDk2TC rI6G8Rnsv3Ce5/r0yBqFXXo9JbYQGXrGU2jjUWILXv5FP/UuLflI6ZrreFMIUngq8wvu37Dm/gAYc cfh9WKWAVHwKbV0l8YRQ/MzuAmlrZ3igm6pGp80zOlHoTyE4FEH3lcSP/gbQjlsQ4xvmBeiN3HIri lzJfZlwhBvNkFA/Fu8p3pGft8ySWLApkfdonOGtMzr64M1pa/Qd1Qb1vj7g0i4lJZcXZxzEAMq/NI VQEHTJ2dxfilgUzIYZPGJb664X1E5ZN+EGs4Dwru3hZp2TVfbppjsGLSbHvufik7gv5DbXXT9klwk YuU++6Pg==; Received: from 195-192-102-148.dyn.cablelink.at ([195.192.102.148] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jkoj6-0007nd-TW; Mon, 15 Jun 2020 13:00:37 +0000 From: Christoph Hellwig To: Al Viro Cc: Arnd Bergmann , Luis Chamberlain , linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/6] exec: cleanup the execve wrappers Date: Mon, 15 Jun 2020 15:00:27 +0200 Message-Id: <20200615130032.931285-2-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200615130032.931285-1-hch@lst.de> References: <20200615130032.931285-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Remove a whole bunch of wrappers that eventually all call __do_execve_file, and consolidate the execvce helpers to: (1) __do_execveat, which is the lowest level helper implementing the actual functionality (2) do_execvat, which is used by all callers that want native pointers (3) do_compat_execve, which is used by all compat syscalls Signed-off-by: Christoph Hellwig --- fs/exec.c | 98 +++++++++++------------------------------ include/linux/binfmts.h | 12 ++--- init/main.c | 7 +-- kernel/umh.c | 16 +++---- 4 files changed, 41 insertions(+), 92 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index e6e8a9a7032784..354fdaa536ae7d 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1815,10 +1815,7 @@ static int exec_binprm(struct linux_binprm *bprm) return 0; } -/* - * sys_execve() executes a new program. - */ -static int __do_execve_file(int fd, struct filename *filename, +static int __do_execveat(int fd, struct filename *filename, struct user_arg_ptr argv, struct user_arg_ptr envp, int flags, struct file *file) @@ -1972,74 +1969,16 @@ static int __do_execve_file(int fd, struct filename *filename, return retval; } -static int do_execveat_common(int fd, struct filename *filename, - struct user_arg_ptr argv, - struct user_arg_ptr envp, - int flags) -{ - return __do_execve_file(fd, filename, argv, envp, flags, NULL); -} - -int do_execve_file(struct file *file, void *__argv, void *__envp) -{ - struct user_arg_ptr argv = { .ptr.native = __argv }; - struct user_arg_ptr envp = { .ptr.native = __envp }; - - return __do_execve_file(AT_FDCWD, NULL, argv, envp, 0, file); -} - -int do_execve(struct filename *filename, - const char __user *const __user *__argv, - const char __user *const __user *__envp) -{ - struct user_arg_ptr argv = { .ptr.native = __argv }; - struct user_arg_ptr envp = { .ptr.native = __envp }; - return do_execveat_common(AT_FDCWD, filename, argv, envp, 0); -} - int do_execveat(int fd, struct filename *filename, const char __user *const __user *__argv, const char __user *const __user *__envp, - int flags) + int flags, struct file *file) { struct user_arg_ptr argv = { .ptr.native = __argv }; struct user_arg_ptr envp = { .ptr.native = __envp }; - return do_execveat_common(fd, filename, argv, envp, flags); -} - -#ifdef CONFIG_COMPAT -static int compat_do_execve(struct filename *filename, - const compat_uptr_t __user *__argv, - const compat_uptr_t __user *__envp) -{ - struct user_arg_ptr argv = { - .is_compat = true, - .ptr.compat = __argv, - }; - struct user_arg_ptr envp = { - .is_compat = true, - .ptr.compat = __envp, - }; - return do_execveat_common(AT_FDCWD, filename, argv, envp, 0); -} - -static int compat_do_execveat(int fd, struct filename *filename, - const compat_uptr_t __user *__argv, - const compat_uptr_t __user *__envp, - int flags) -{ - struct user_arg_ptr argv = { - .is_compat = true, - .ptr.compat = __argv, - }; - struct user_arg_ptr envp = { - .is_compat = true, - .ptr.compat = __envp, - }; - return do_execveat_common(fd, filename, argv, envp, flags); + return __do_execveat(fd, filename, argv, envp, flags, file); } -#endif void set_binfmt(struct linux_binfmt *new) { @@ -2070,7 +2009,7 @@ SYSCALL_DEFINE3(execve, const char __user *const __user *, argv, const char __user *const __user *, envp) { - return do_execve(getname(filename), argv, envp); + return do_execveat(AT_FDCWD, getname(filename), argv, envp, 0, NULL); } SYSCALL_DEFINE5(execveat, @@ -2080,18 +2019,34 @@ SYSCALL_DEFINE5(execveat, int, flags) { int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0; + struct filename *name = getname_flags(filename, lookup_flags, NULL); - return do_execveat(fd, - getname_flags(filename, lookup_flags, NULL), - argv, envp, flags); + return do_execveat(fd, name, argv, envp, flags, NULL); } #ifdef CONFIG_COMPAT +static int do_compat_execve(int fd, struct filename *filename, + const compat_uptr_t __user *__argv, + const compat_uptr_t __user *__envp, + int flags) +{ + struct user_arg_ptr argv = { + .is_compat = true, + .ptr.compat = __argv, + }; + struct user_arg_ptr envp = { + .is_compat = true, + .ptr.compat = __envp, + }; + + return __do_execveat(fd, filename, argv, envp, flags, NULL); +} + COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename, const compat_uptr_t __user *, argv, const compat_uptr_t __user *, envp) { - return compat_do_execve(getname(filename), argv, envp); + return do_compat_execve(AT_FDCWD, getname(filename), argv, envp, 0); } COMPAT_SYSCALL_DEFINE5(execveat, int, fd, @@ -2101,9 +2056,8 @@ COMPAT_SYSCALL_DEFINE5(execveat, int, fd, int, flags) { int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0; + struct filename *name = getname_flags(filename, lookup_flags, NULL); - return compat_do_execveat(fd, - getname_flags(filename, lookup_flags, NULL), - argv, envp, flags); + return do_compat_execve(fd, name, argv, envp, flags); } #endif diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h index 4a20b7517dd036..bed702e4b1fbd9 100644 --- a/include/linux/binfmts.h +++ b/include/linux/binfmts.h @@ -134,13 +134,9 @@ int copy_string_kernel(const char *arg, struct linux_binprm *bprm); extern void set_binfmt(struct linux_binfmt *new); extern ssize_t read_code(struct file *, unsigned long, loff_t, size_t); -extern int do_execve(struct filename *, - const char __user * const __user *, - const char __user * const __user *); -extern int do_execveat(int, struct filename *, - const char __user * const __user *, - const char __user * const __user *, - int); -int do_execve_file(struct file *file, void *__argv, void *__envp); +int do_execveat(int fd, struct filename *filename, + const char __user *const __user *__argv, + const char __user *const __user *__envp, + int flags, struct file *file); #endif /* _LINUX_BINFMTS_H */ diff --git a/init/main.c b/init/main.c index 0ead83e86b5aa2..838950ea7bca22 100644 --- a/init/main.c +++ b/init/main.c @@ -1329,9 +1329,10 @@ static int run_init_process(const char *init_filename) pr_debug(" with environment:\n"); for (p = envp_init; *p; p++) pr_debug(" %s\n", *p); - return do_execve(getname_kernel(init_filename), - (const char __user *const __user *)argv_init, - (const char __user *const __user *)envp_init); + return do_execveat(AT_FDCWD, getname_kernel(init_filename), + (const char __user *const __user *)argv_init, + (const char __user *const __user *)envp_init, + 0, NULL); } static int try_to_run_init_process(const char *init_filename) diff --git a/kernel/umh.c b/kernel/umh.c index 79f139a7ca03c6..7aa9a5817582ca 100644 --- a/kernel/umh.c +++ b/kernel/umh.c @@ -103,15 +103,13 @@ static int call_usermodehelper_exec_async(void *data) commit_creds(new); sub_info->pid = task_pid_nr(current); - if (sub_info->file) { - retval = do_execve_file(sub_info->file, - sub_info->argv, sub_info->envp); - if (!retval) - current->flags |= PF_UMH; - } else - retval = do_execve(getname_kernel(sub_info->path), - (const char __user *const __user *)sub_info->argv, - (const char __user *const __user *)sub_info->envp); + retval = do_execveat(AT_FDCWD, + sub_info->path ? getname_kernel(sub_info->path) : NULL, + (const char __user *const __user *)sub_info->argv, + (const char __user *const __user *)sub_info->envp, + 0, sub_info->file); + if (sub_info->file && !retval) + current->flags |= PF_UMH; out: sub_info->retval = retval; /* From patchwork Mon Jun 15 13:00:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11604903 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 A725892A for ; Mon, 15 Jun 2020 13:01:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7586A20757 for ; Mon, 15 Jun 2020 13:01:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="O+zn5Tp2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730339AbgFONAs (ORCPT ); Mon, 15 Jun 2020 09:00:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52370 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730291AbgFONAp (ORCPT ); Mon, 15 Jun 2020 09:00:45 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5B3AFC05BD43; Mon, 15 Jun 2020 06:00:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=rpFgFIoTb0aGoKIT7/JiwFrDf3IrsE97GBcxnYtYTnw=; b=O+zn5Tp2u7TqQR3d8hGCqey8vR tmoTgaHHj79VKrOkdc5+K+MwfXw3/F9AAdRxK1Uxr3djNgKpHvjkR1AC6HF+o8LVpmj8VHDw9dyl3 CXvH16a63bpVsTQgrtq298oLi0rZcfDCl2qicTYiWJPQgDt8XdxteuUz6myd66Wi6DkxdQyyy9VX4 inpb/lu1VP5kuFf4YMnBF9Zm/n/W0DAfQ+TV5V2CVxz+grBD/XhBF0q/fxyno5on8VrYJkBeZBfcU oZvDfx0+K//aqoQjx7o0Lv/xU9DwzXtk8LK49GVzf1za57+T5OvR1eKB/2ZCjnr9xteDctF1mGIaQ pk6f7jyg==; Received: from 195-192-102-148.dyn.cablelink.at ([195.192.102.148] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jkoj9-0007pR-GH; Mon, 15 Jun 2020 13:00:40 +0000 From: Christoph Hellwig To: Al Viro Cc: Arnd Bergmann , Luis Chamberlain , linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/6] exec: simplify the compat syscall handling Date: Mon, 15 Jun 2020 15:00:28 +0200 Message-Id: <20200615130032.931285-3-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200615130032.931285-1-hch@lst.de> References: <20200615130032.931285-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org The only differenence betweeen the compat exec* syscalls and their native versions is that compat_ptr sign extension, and the fact that the pointer arithmetics for the two dimensional arrays needs to use the compat pointer size. Instead of the compat wrappers and the struct user_arg_ptr machinery just use in_compat_syscall() to do the right thing for the compat case deep inside get_user_arg_ptr(). Signed-off-by: Christoph Hellwig --- arch/arm64/include/asm/unistd32.h | 4 +- arch/mips/kernel/syscalls/syscall_n32.tbl | 4 +- arch/mips/kernel/syscalls/syscall_o32.tbl | 4 +- arch/parisc/kernel/syscalls/syscall.tbl | 4 +- arch/powerpc/kernel/syscalls/syscall.tbl | 4 +- arch/s390/kernel/syscalls/syscall.tbl | 4 +- arch/sparc/kernel/syscalls.S | 4 +- arch/x86/entry/syscalls/syscall_32.tbl | 4 +- fs/exec.c | 89 ++++++------------- include/linux/compat.h | 7 -- include/uapi/asm-generic/unistd.h | 4 +- tools/include/uapi/asm-generic/unistd.h | 4 +- .../arch/powerpc/entry/syscalls/syscall.tbl | 4 +- .../perf/arch/s390/entry/syscalls/syscall.tbl | 4 +- 14 files changed, 53 insertions(+), 91 deletions(-) diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h index 6d95d0c8bf2f47..141f5d2ff1c34f 100644 --- a/arch/arm64/include/asm/unistd32.h +++ b/arch/arm64/include/asm/unistd32.h @@ -33,7 +33,7 @@ __SYSCALL(__NR_link, sys_link) #define __NR_unlink 10 __SYSCALL(__NR_unlink, sys_unlink) #define __NR_execve 11 -__SYSCALL(__NR_execve, compat_sys_execve) +__SYSCALL(__NR_execve, sys_execve) #define __NR_chdir 12 __SYSCALL(__NR_chdir, sys_chdir) /* 13 was sys_time */ @@ -785,7 +785,7 @@ __SYSCALL(__NR_memfd_create, sys_memfd_create) #define __NR_bpf 386 __SYSCALL(__NR_bpf, sys_bpf) #define __NR_execveat 387 -__SYSCALL(__NR_execveat, compat_sys_execveat) +__SYSCALL(__NR_execveat, sys_execveat) #define __NR_userfaultfd 388 __SYSCALL(__NR_userfaultfd, sys_userfaultfd) #define __NR_membarrier 389 diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl index f777141f52568f..e861b5ab7179c9 100644 --- a/arch/mips/kernel/syscalls/syscall_n32.tbl +++ b/arch/mips/kernel/syscalls/syscall_n32.tbl @@ -64,7 +64,7 @@ 54 n32 getsockopt compat_sys_getsockopt 55 n32 clone __sys_clone 56 n32 fork __sys_fork -57 n32 execve compat_sys_execve +57 n32 execve sys_execve 58 n32 exit sys_exit 59 n32 wait4 compat_sys_wait4 60 n32 kill sys_kill @@ -328,7 +328,7 @@ 317 n32 getrandom sys_getrandom 318 n32 memfd_create sys_memfd_create 319 n32 bpf sys_bpf -320 n32 execveat compat_sys_execveat +320 n32 execveat sys_execveat 321 n32 userfaultfd sys_userfaultfd 322 n32 membarrier sys_membarrier 323 n32 mlock2 sys_mlock2 diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl index 13280625d312e9..bba80f74e9968e 100644 --- a/arch/mips/kernel/syscalls/syscall_o32.tbl +++ b/arch/mips/kernel/syscalls/syscall_o32.tbl @@ -18,7 +18,7 @@ 8 o32 creat sys_creat 9 o32 link sys_link 10 o32 unlink sys_unlink -11 o32 execve sys_execve compat_sys_execve +11 o32 execve sys_execve 12 o32 chdir sys_chdir 13 o32 time sys_time32 14 o32 mknod sys_mknod @@ -367,7 +367,7 @@ 353 o32 getrandom sys_getrandom 354 o32 memfd_create sys_memfd_create 355 o32 bpf sys_bpf -356 o32 execveat sys_execveat compat_sys_execveat +356 o32 execveat sys_execveat 357 o32 userfaultfd sys_userfaultfd 358 o32 membarrier sys_membarrier 359 o32 mlock2 sys_mlock2 diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl index 5a758fa6ec5242..23fa0d0edf3384 100644 --- a/arch/parisc/kernel/syscalls/syscall.tbl +++ b/arch/parisc/kernel/syscalls/syscall.tbl @@ -18,7 +18,7 @@ 8 common creat sys_creat 9 common link sys_link 10 common unlink sys_unlink -11 common execve sys_execve compat_sys_execve +11 common execve sys_execve 12 common chdir sys_chdir 13 32 time sys_time32 13 64 time sys_time @@ -385,7 +385,7 @@ 339 common getrandom sys_getrandom 340 common memfd_create sys_memfd_create 341 common bpf sys_bpf -342 common execveat sys_execveat compat_sys_execveat +342 common execveat sys_execveat 343 common membarrier sys_membarrier 344 common userfaultfd sys_userfaultfd 345 common mlock2 sys_mlock2 diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl index f833a319082247..c52cdab89dc0ae 100644 --- a/arch/powerpc/kernel/syscalls/syscall.tbl +++ b/arch/powerpc/kernel/syscalls/syscall.tbl @@ -20,7 +20,7 @@ 8 common creat sys_creat 9 common link sys_link 10 common unlink sys_unlink -11 nospu execve sys_execve compat_sys_execve +11 nospu execve sys_execve 12 common chdir sys_chdir 13 32 time sys_time32 13 64 time sys_time @@ -460,7 +460,7 @@ 359 common getrandom sys_getrandom 360 common memfd_create sys_memfd_create 361 common bpf sys_bpf -362 nospu execveat sys_execveat compat_sys_execveat +362 nospu execveat sys_execveat 363 32 switch_endian sys_ni_syscall 363 64 switch_endian sys_switch_endian 363 spu switch_endian sys_ni_syscall diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl index bfdcb763395735..bd2275db2026ea 100644 --- a/arch/s390/kernel/syscalls/syscall.tbl +++ b/arch/s390/kernel/syscalls/syscall.tbl @@ -18,7 +18,7 @@ 8 common creat sys_creat sys_creat 9 common link sys_link sys_link 10 common unlink sys_unlink sys_unlink -11 common execve sys_execve compat_sys_execve +11 common execve sys_execve sys_execve 12 common chdir sys_chdir sys_chdir 13 32 time - sys_time32 14 common mknod sys_mknod sys_mknod @@ -361,7 +361,7 @@ 351 common bpf sys_bpf sys_bpf 352 common s390_pci_mmio_write sys_s390_pci_mmio_write sys_s390_pci_mmio_write 353 common s390_pci_mmio_read sys_s390_pci_mmio_read sys_s390_pci_mmio_read -354 common execveat sys_execveat compat_sys_execveat +354 common execveat sys_execveat sys_execveat 355 common userfaultfd sys_userfaultfd sys_userfaultfd 356 common membarrier sys_membarrier sys_membarrier 357 common recvmmsg sys_recvmmsg compat_sys_recvmmsg_time32 diff --git a/arch/sparc/kernel/syscalls.S b/arch/sparc/kernel/syscalls.S index db42b4fb370844..70463972152a92 100644 --- a/arch/sparc/kernel/syscalls.S +++ b/arch/sparc/kernel/syscalls.S @@ -16,12 +16,12 @@ sys64_execveat: sunos_execv: mov %g0, %o2 sys32_execve: - set compat_sys_execve, %g1 + set sys_execve, %g1 jmpl %g1, %g0 flushw sys32_execveat: - set compat_sys_execveat, %g1 + set sys_execveat, %g1 jmpl %g1, %g0 flushw #endif diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index d8f8a1a69ed11f..2b1eccd3f8f697 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -22,7 +22,7 @@ 8 i386 creat sys_creat 9 i386 link sys_link 10 i386 unlink sys_unlink -11 i386 execve sys_execve compat_sys_execve +11 i386 execve sys_execve 12 i386 chdir sys_chdir 13 i386 time sys_time32 14 i386 mknod sys_mknod @@ -369,7 +369,7 @@ 355 i386 getrandom sys_getrandom 356 i386 memfd_create sys_memfd_create 357 i386 bpf sys_bpf -358 i386 execveat sys_execveat compat_sys_execveat +358 i386 execveat sys_execveat 359 i386 socket sys_socket 360 i386 socketpair sys_socketpair 361 i386 bind sys_bind diff --git a/fs/exec.c b/fs/exec.c index 354fdaa536ae7d..94107eceda8a67 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -386,34 +386,25 @@ static int bprm_mm_init(struct linux_binprm *bprm) return err; } -struct user_arg_ptr { -#ifdef CONFIG_COMPAT - bool is_compat; -#endif - union { - const char __user *const __user *native; -#ifdef CONFIG_COMPAT - const compat_uptr_t __user *compat; -#endif - } ptr; -}; - -static const char __user *get_user_arg_ptr(struct user_arg_ptr argv, int nr) +static const char __user * +get_user_arg_ptr(const char __user *const __user *argv, int nr) { const char __user *native; #ifdef CONFIG_COMPAT - if (unlikely(argv.is_compat)) { + if (in_compat_syscall()) { + const compat_uptr_t __user *compat_argv = + compat_ptr((unsigned long)argv); compat_uptr_t compat; - if (get_user(compat, argv.ptr.compat + nr)) + if (get_user(compat, compat_argv + nr)) return ERR_PTR(-EFAULT); return compat_ptr(compat); } #endif - if (get_user(native, argv.ptr.native + nr)) + if (get_user(native, argv + nr)) return ERR_PTR(-EFAULT); return native; @@ -422,11 +413,11 @@ static const char __user *get_user_arg_ptr(struct user_arg_ptr argv, int nr) /* * count() counts the number of strings in array ARGV. */ -static int count(struct user_arg_ptr argv, int max) +static int count(const char __user *const __user *argv, int max) { int i = 0; - if (argv.ptr.native != NULL) { + if (argv) { for (;;) { const char __user *p = get_user_arg_ptr(argv, i); @@ -449,7 +440,8 @@ static int count(struct user_arg_ptr argv, int max) } static int prepare_arg_pages(struct linux_binprm *bprm, - struct user_arg_ptr argv, struct user_arg_ptr envp) + const char __user *const __user *argv, + const char __user *const __user *envp) { unsigned long limit, ptr_size; @@ -497,7 +489,7 @@ static int prepare_arg_pages(struct linux_binprm *bprm, * processes's memory to the new process's stack. The call to get_user_pages() * ensures the destination page is created and not swapped out. */ -static int copy_strings(int argc, struct user_arg_ptr argv, +static int copy_strings(int argc, const char __user *const __user *argv, struct linux_binprm *bprm) { struct page *kmapped_page = NULL; @@ -1815,10 +1807,10 @@ static int exec_binprm(struct linux_binprm *bprm) return 0; } -static int __do_execveat(int fd, struct filename *filename, - struct user_arg_ptr argv, - struct user_arg_ptr envp, - int flags, struct file *file) +int do_execveat(int fd, struct filename *filename, + const char __user *const __user *argv, + const char __user *const __user *envp, + int flags, struct file *file) { char *pathbuf = NULL; struct linux_binprm *bprm; @@ -1969,17 +1961,6 @@ static int __do_execveat(int fd, struct filename *filename, return retval; } -int do_execveat(int fd, struct filename *filename, - const char __user *const __user *__argv, - const char __user *const __user *__envp, - int flags, struct file *file) -{ - struct user_arg_ptr argv = { .ptr.native = __argv }; - struct user_arg_ptr envp = { .ptr.native = __envp }; - - return __do_execveat(fd, filename, argv, envp, flags, file); -} - void set_binfmt(struct linux_binfmt *new) { struct mm_struct *mm = current->mm; @@ -2024,40 +2005,28 @@ SYSCALL_DEFINE5(execveat, return do_execveat(fd, name, argv, envp, flags, NULL); } -#ifdef CONFIG_COMPAT -static int do_compat_execve(int fd, struct filename *filename, - const compat_uptr_t __user *__argv, - const compat_uptr_t __user *__envp, - int flags) -{ - struct user_arg_ptr argv = { - .is_compat = true, - .ptr.compat = __argv, - }; - struct user_arg_ptr envp = { - .is_compat = true, - .ptr.compat = __envp, - }; - - return __do_execveat(fd, filename, argv, envp, flags, NULL); -} - +/* + * x32 syscalls are listed in the same table as x86_64 ones, so we need to + * define compat syscalls that are exactly the same as the native version for + * the syscall table machinery to work. Sigh.. + */ +#ifdef CONFIG_X86_X32 COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename, - const compat_uptr_t __user *, argv, - const compat_uptr_t __user *, envp) + const char __user *const __user *, argv, + const char __user *const __user *, envp) { - return do_compat_execve(AT_FDCWD, getname(filename), argv, envp, 0); + return do_execveat(AT_FDCWD, getname(filename), argv, envp, 0, NULL); } COMPAT_SYSCALL_DEFINE5(execveat, int, fd, const char __user *, filename, - const compat_uptr_t __user *, argv, - const compat_uptr_t __user *, envp, + const char __user *const __user *, argv, + const char __user *const __user *, envp, int, flags) { int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0; struct filename *name = getname_flags(filename, lookup_flags, NULL); - return do_compat_execve(fd, name, argv, envp, flags); + return do_execveat(fd, name, argv, envp, flags, NULL); } -#endif +#endif /* CONFIG_X86_X32 */ diff --git a/include/linux/compat.h b/include/linux/compat.h index e90100c0de72e4..5e8f6a588e0d43 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -752,10 +752,6 @@ asmlinkage long compat_sys_recvmsg(int fd, struct compat_msghdr __user *msg, asmlinkage long compat_sys_keyctl(u32 option, u32 arg2, u32 arg3, u32 arg4, u32 arg5); -/* arch/example/kernel/sys_example.c */ -asmlinkage long compat_sys_execve(const char __user *filename, const compat_uptr_t __user *argv, - const compat_uptr_t __user *envp); - /* mm/fadvise.c: No generic prototype for fadvise64_64 */ /* mm/, CONFIG_MMU only */ @@ -806,9 +802,6 @@ asmlinkage ssize_t compat_sys_process_vm_writev(compat_pid_t pid, const struct compat_iovec __user *lvec, compat_ulong_t liovcnt, const struct compat_iovec __user *rvec, compat_ulong_t riovcnt, compat_ulong_t flags); -asmlinkage long compat_sys_execveat(int dfd, const char __user *filename, - const compat_uptr_t __user *argv, - const compat_uptr_t __user *envp, int flags); asmlinkage ssize_t compat_sys_preadv2(compat_ulong_t fd, const struct compat_iovec __user *vec, compat_ulong_t vlen, u32 pos_low, u32 pos_high, rwf_t flags); diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h index f4a01305d9a65c..c639d04a094b8b 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h @@ -640,7 +640,7 @@ __SC_COMP(__NR_keyctl, sys_keyctl, compat_sys_keyctl) #define __NR_clone 220 __SYSCALL(__NR_clone, sys_clone) #define __NR_execve 221 -__SC_COMP(__NR_execve, sys_execve, compat_sys_execve) +__SYSCALL(__NR_execve, sys_execve) #define __NR3264_mmap 222 __SC_3264(__NR3264_mmap, sys_mmap2, sys_mmap) @@ -751,7 +751,7 @@ __SYSCALL(__NR_memfd_create, sys_memfd_create) #define __NR_bpf 280 __SYSCALL(__NR_bpf, sys_bpf) #define __NR_execveat 281 -__SC_COMP(__NR_execveat, sys_execveat, compat_sys_execveat) +__SYSCALL(__NR_execveat, sys_execveat) #define __NR_userfaultfd 282 __SYSCALL(__NR_userfaultfd, sys_userfaultfd) #define __NR_membarrier 283 diff --git a/tools/include/uapi/asm-generic/unistd.h b/tools/include/uapi/asm-generic/unistd.h index 3a3201e4618ef8..a6dbc8af8bd577 100644 --- a/tools/include/uapi/asm-generic/unistd.h +++ b/tools/include/uapi/asm-generic/unistd.h @@ -640,7 +640,7 @@ __SC_COMP(__NR_keyctl, sys_keyctl, compat_sys_keyctl) #define __NR_clone 220 __SYSCALL(__NR_clone, sys_clone) #define __NR_execve 221 -__SC_COMP(__NR_execve, sys_execve, compat_sys_execve) +__SYSCALL(__NR_execve, sys_execve) #define __NR3264_mmap 222 __SC_3264(__NR3264_mmap, sys_mmap2, sys_mmap) @@ -751,7 +751,7 @@ __SYSCALL(__NR_memfd_create, sys_memfd_create) #define __NR_bpf 280 __SYSCALL(__NR_bpf, sys_bpf) #define __NR_execveat 281 -__SC_COMP(__NR_execveat, sys_execveat, compat_sys_execveat) +__SYSCALL(__NR_execveat, sys_execveat) #define __NR_userfaultfd 282 __SYSCALL(__NR_userfaultfd, sys_userfaultfd) #define __NR_membarrier 283 diff --git a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl index 35b61bfc1b1ae9..42bf8b461a0ed6 100644 --- a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl +++ b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl @@ -18,7 +18,7 @@ 8 common creat sys_creat 9 common link sys_link 10 common unlink sys_unlink -11 nospu execve sys_execve compat_sys_execve +11 nospu execve sys_execve sys_execve 12 common chdir sys_chdir 13 32 time sys_time32 13 64 time sys_time @@ -454,7 +454,7 @@ 359 common getrandom sys_getrandom 360 common memfd_create sys_memfd_create 361 common bpf sys_bpf -362 nospu execveat sys_execveat compat_sys_execveat +362 nospu execveat sys_execveat sys_execveat 363 32 switch_endian sys_ni_syscall 363 64 switch_endian ppc_switch_endian 363 spu switch_endian sys_ni_syscall diff --git a/tools/perf/arch/s390/entry/syscalls/syscall.tbl b/tools/perf/arch/s390/entry/syscalls/syscall.tbl index b38d48464368dc..f3c16f2d9746ac 100644 --- a/tools/perf/arch/s390/entry/syscalls/syscall.tbl +++ b/tools/perf/arch/s390/entry/syscalls/syscall.tbl @@ -18,7 +18,7 @@ 8 common creat sys_creat compat_sys_creat 9 common link sys_link compat_sys_link 10 common unlink sys_unlink compat_sys_unlink -11 common execve sys_execve compat_sys_execve +11 common execve sys_execve sys_execve 12 common chdir sys_chdir compat_sys_chdir 13 32 time - compat_sys_time 14 common mknod sys_mknod compat_sys_mknod @@ -361,7 +361,7 @@ 351 common bpf sys_bpf compat_sys_bpf 352 common s390_pci_mmio_write sys_s390_pci_mmio_write compat_sys_s390_pci_mmio_write 353 common s390_pci_mmio_read sys_s390_pci_mmio_read compat_sys_s390_pci_mmio_read -354 common execveat sys_execveat compat_sys_execveat +354 common execveat sys_execveat sys_execveat 355 common userfaultfd sys_userfaultfd sys_userfaultfd 356 common membarrier sys_membarrier sys_membarrier 357 common recvmmsg sys_recvmmsg compat_sys_recvmmsg From patchwork Mon Jun 15 13:00:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11604907 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 EB42992A for ; Mon, 15 Jun 2020 13:02:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D40B82076A for ; Mon, 15 Jun 2020 13:02:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="IH5rGn9P" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730409AbgFONBv (ORCPT ); Mon, 15 Jun 2020 09:01:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52392 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730357AbgFONAx (ORCPT ); Mon, 15 Jun 2020 09:00:53 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EAEC7C061A0E; Mon, 15 Jun 2020 06:00:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=SM2vwUzS1lS5JPIE11hnWuY4020BCObQGWMmPP5iv+U=; b=IH5rGn9PdguQ/MJmSQeWa39CS5 xYhYsW2KOhQ7JARWxoLOcrAASLH7Mg9nT9bOWMT2QsLkXgR1PiM53SOGyGhcJ/pOT2uQ2oAoMYCea FMpsAX3009azgrIIbJwwa4ZNiutR+PuL4iA9/LrosE5OcMBEFLoo9a/4A5MCyCVQaW8T31HswmFa0 E+juO8zuJ7Y80JJqixESrR+bfEJ20AqTuLGcZIjJ8Ej5wzqh4V67dC0vKsf1bGZNzGSX+tMr9bm2o d3vFWAelmSJD0mv1AatU2ckIMAIiODHoH1OoVQriwq0EsCjoMCtY8lbWHO55db++0T6OOrImMQcPW J59ZlUjA==; Received: from 195-192-102-148.dyn.cablelink.at ([195.192.102.148] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jkojC-0007sl-3K; Mon, 15 Jun 2020 13:00:42 +0000 From: Christoph Hellwig To: Al Viro Cc: Arnd Bergmann , Luis Chamberlain , linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/6] exec: cleanup the count() function Date: Mon, 15 Jun 2020 15:00:29 +0200 Message-Id: <20200615130032.931285-4-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200615130032.931285-1-hch@lst.de> References: <20200615130032.931285-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Remove the max argument as it is hard wired to MAX_ARG_STRINGS, and give the function a slightly less generic name. Signed-off-by: Christoph Hellwig --- fs/exec.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 94107eceda8a67..6e4d9d1ffa35fa 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -411,9 +411,9 @@ get_user_arg_ptr(const char __user *const __user *argv, int nr) } /* - * count() counts the number of strings in array ARGV. + * count_strings() counts the number of strings in array ARGV. */ -static int count(const char __user *const __user *argv, int max) +static int count_strings(const char __user *const __user *argv) { int i = 0; @@ -427,7 +427,7 @@ static int count(const char __user *const __user *argv, int max) if (IS_ERR(p)) return -EFAULT; - if (i >= max) + if (i >= MAX_ARG_STRINGS) return -E2BIG; ++i; @@ -445,11 +445,11 @@ static int prepare_arg_pages(struct linux_binprm *bprm, { unsigned long limit, ptr_size; - bprm->argc = count(argv, MAX_ARG_STRINGS); + bprm->argc = count_strings(argv); if (bprm->argc < 0) return bprm->argc; - bprm->envc = count(envp, MAX_ARG_STRINGS); + bprm->envc = count_strings(envp); if (bprm->envc < 0) return bprm->envc; From patchwork Mon Jun 15 13:00:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11604887 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 1A2E792A for ; Mon, 15 Jun 2020 13:01:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EFC38207D4 for ; Mon, 15 Jun 2020 13:01:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="o2RhlHWQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730377AbgFONA5 (ORCPT ); Mon, 15 Jun 2020 09:00:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52402 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730365AbgFONAz (ORCPT ); Mon, 15 Jun 2020 09:00:55 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 232CBC05BD43; Mon, 15 Jun 2020 06:00:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=ZZGHsoXTnXgAmRUOcfo4lrl/+NT7PZj7FPHx1htWx6U=; b=o2RhlHWQ1U73lI4UBKreMeuh1d V96c20aFyOomEbcWIphJ3pyFjo5ItIgAm/KJIp5Sh1J+gPI5HXmI2YG1i19dy0QhOUqa5pA81t8KD 8/u9BQVaEmeq5snWMfRRjHfqH9pEVoWlA2NmGYotUCCMF4BVxoOflkeOJwlSnXr92QyTzmss9vYvp 2FljztR/Rre+glKjpQSOqFsSl+so6GyRD1Gz9+tBqcY5EzihIIRZ/cHIDuBAmZeBeHYYSHNAPg77K 9wpc/KR89+aovx2wkhPYW15B4NlsBqIVk/0t+F3bcJ4qSvUnBH8prQVTmMXJr70LHsZmWncdVjCvE mVSsqGbw==; Received: from 195-192-102-148.dyn.cablelink.at ([195.192.102.148] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jkojF-0007w7-BU; Mon, 15 Jun 2020 13:00:45 +0000 From: Christoph Hellwig To: Al Viro Cc: Arnd Bergmann , Luis Chamberlain , linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 4/6] exec: split prepare_arg_pages Date: Mon, 15 Jun 2020 15:00:30 +0200 Message-Id: <20200615130032.931285-5-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200615130032.931285-1-hch@lst.de> References: <20200615130032.931285-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Move counting the arguments and enviroment variables out of prepare_arg_pages and rename the rest of the function to check_arg_limit. This prepares for a version of do_execvat that takes kernel pointers. Signed-off-by: Christoph Hellwig --- fs/exec.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 6e4d9d1ffa35fa..696b1e8180d7d8 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -439,20 +439,10 @@ static int count_strings(const char __user *const __user *argv) return i; } -static int prepare_arg_pages(struct linux_binprm *bprm, - const char __user *const __user *argv, - const char __user *const __user *envp) +static int check_arg_limit(struct linux_binprm *bprm) { unsigned long limit, ptr_size; - bprm->argc = count_strings(argv); - if (bprm->argc < 0) - return bprm->argc; - - bprm->envc = count_strings(envp); - if (bprm->envc < 0) - return bprm->envc; - /* * Limit to 1/4 of the max stack size or 3/4 of _STK_LIM * (whichever is smaller) for the argv+env strings. @@ -1890,7 +1880,19 @@ int do_execveat(int fd, struct filename *filename, if (retval) goto out_unmark; - retval = prepare_arg_pages(bprm, argv, envp); + bprm->argc = count_strings(argv); + if (bprm->argc < 0) { + retval = bprm->argc; + goto out; + } + + bprm->envc = count_strings(envp); + if (bprm->envc < 0) { + retval = bprm->envc; + goto out; + } + + retval = check_arg_limit(bprm); if (retval < 0) goto out; From patchwork Mon Jun 15 13:00:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11604895 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 F30341392 for ; Mon, 15 Jun 2020 13:01:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D6E20207D3 for ; Mon, 15 Jun 2020 13:01:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="SbuDdgG9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730370AbgFONA4 (ORCPT ); Mon, 15 Jun 2020 09:00:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730364AbgFONAz (ORCPT ); Mon, 15 Jun 2020 09:00:55 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CA15DC061A0E; Mon, 15 Jun 2020 06:00:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=1WDBC7LjIDLfthejFif7qd4aQJk//njgbp0UqqID8LI=; b=SbuDdgG9DUPs6mvsGQMt+8misj 5kHBZGkHxM3jQ7zqbZ/ewsnJj/VY7RX0rh/TMfrCJ6z2f6BHbL+MR6wlcBzjKnVj4A/lET5PMR7Lt 9WtYHkwGMw9P6UltieiCOTF1uQBs42hlEmiNzkZjmMknpHyn6MNx2hrFvwqAEsIxLpbQqsfgtnmrz mCR8ZP+UgFeyi3+LjwsR+01g1phSvfbc/W+EebhRjftc35Am4tXC6xdpoSh0KXpZ7jCNwmtJRCVKS xn/O5+JIL0Q1YduEAE1fqSrfMNJe1o1QEZ+3vc+9JCVxsJ1xoUcqhhbCM9OZCeJDXieTdvYOIXC07 Dqn7Uiww==; Received: from 195-192-102-148.dyn.cablelink.at ([195.192.102.148] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jkojH-0007yw-T8; Mon, 15 Jun 2020 13:00:48 +0000 From: Christoph Hellwig To: Al Viro Cc: Arnd Bergmann , Luis Chamberlain , linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 5/6] exec: add a kernel_execveat helper Date: Mon, 15 Jun 2020 15:00:31 +0200 Message-Id: <20200615130032.931285-6-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200615130032.931285-1-hch@lst.de> References: <20200615130032.931285-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Add a kernel_execveat helper to execute a binary with kernel space argv and envp pointers. Switch executing init and user mode helpers to this new helper instead of relying on the implicit set_fs(KERNEL_DS) for early init code and kernel threads, and move the getname call into the do_execve helper. Signed-off-by: Christoph Hellwig --- fs/exec.c | 116 +++++++++++++++++++++++++++++++--------- include/linux/binfmts.h | 6 +-- init/main.c | 6 +-- kernel/umh.c | 8 ++- 4 files changed, 97 insertions(+), 39 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 696b1e8180d7d8..9e16d56aa53e86 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -439,6 +439,21 @@ static int count_strings(const char __user *const __user *argv) return i; } +static int count_kernel_strings(const char *const *argv) +{ + int i; + + if (!argv) + return 0; + + for (i = 0; argv[i]; i++) { + if (i >= MAX_ARG_STRINGS) + return -E2BIG; + } + + return i; +} + static int check_arg_limit(struct linux_binprm *bprm) { unsigned long limit, ptr_size; @@ -615,6 +630,19 @@ int copy_string_kernel(const char *arg, struct linux_binprm *bprm) } EXPORT_SYMBOL(copy_string_kernel); +static int copy_strings_kernel(int argc, const char *const *argv, + struct linux_binprm *bprm) +{ + int ret; + + while (argc-- > 0) { + ret = copy_string_kernel(argv[argc], bprm); + if (ret) + break; + } + return ret; +} + #ifdef CONFIG_MMU /* @@ -1797,9 +1825,11 @@ static int exec_binprm(struct linux_binprm *bprm) return 0; } -int do_execveat(int fd, struct filename *filename, +static int __do_execveat(int fd, struct filename *filename, const char __user *const __user *argv, const char __user *const __user *envp, + const char *const *kernel_argv, + const char *const *kernel_envp, int flags, struct file *file) { char *pathbuf = NULL; @@ -1880,16 +1910,30 @@ int do_execveat(int fd, struct filename *filename, if (retval) goto out_unmark; - bprm->argc = count_strings(argv); - if (bprm->argc < 0) { - retval = bprm->argc; - goto out; - } + if (unlikely(kernel_argv)) { + bprm->argc = count_kernel_strings(kernel_argv); + if (bprm->argc < 0) { + retval = bprm->argc; + goto out; + } - bprm->envc = count_strings(envp); - if (bprm->envc < 0) { - retval = bprm->envc; - goto out; + bprm->envc = count_kernel_strings(kernel_envp); + if (bprm->envc < 0) { + retval = bprm->envc; + goto out; + } + } else { + bprm->argc = count_strings(argv); + if (bprm->argc < 0) { + retval = bprm->argc; + goto out; + } + + bprm->envc = count_strings(envp); + if (bprm->envc < 0) { + retval = bprm->envc; + goto out; + } } retval = check_arg_limit(bprm); @@ -1906,13 +1950,22 @@ int do_execveat(int fd, struct filename *filename, goto out; bprm->exec = bprm->p; - retval = copy_strings(bprm->envc, envp, bprm); - if (retval < 0) - goto out; - retval = copy_strings(bprm->argc, argv, bprm); - if (retval < 0) - goto out; + if (unlikely(kernel_argv)) { + retval = copy_strings_kernel(bprm->envc, kernel_envp, bprm); + if (retval < 0) + goto out; + retval = copy_strings_kernel(bprm->argc, kernel_argv, bprm); + if (retval < 0) + goto out; + } else { + retval = copy_strings(bprm->envc, envp, bprm); + if (retval < 0) + goto out; + retval = copy_strings(bprm->argc, argv, bprm); + if (retval < 0) + goto out; + } retval = exec_binprm(bprm); if (retval < 0) @@ -1963,6 +2016,23 @@ int do_execveat(int fd, struct filename *filename, return retval; } +static int do_execveat(int fd, const char *filename, + const char __user *const __user *argv, + const char __user *const __user *envp, int flags) +{ + int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0; + struct filename *name = getname_flags(filename, lookup_flags, NULL); + + return __do_execveat(fd, name, argv, envp, NULL, NULL, flags, NULL); +} + +int kernel_execveat(int fd, const char *filename, const char *const *argv, + const char *const *envp, int flags, struct file *file) +{ + return __do_execveat(fd, getname_kernel(filename), NULL, NULL, argv, + envp, flags, file); +} + void set_binfmt(struct linux_binfmt *new) { struct mm_struct *mm = current->mm; @@ -1992,7 +2062,7 @@ SYSCALL_DEFINE3(execve, const char __user *const __user *, argv, const char __user *const __user *, envp) { - return do_execveat(AT_FDCWD, getname(filename), argv, envp, 0, NULL); + return do_execveat(AT_FDCWD, filename, argv, envp, 0); } SYSCALL_DEFINE5(execveat, @@ -2001,10 +2071,7 @@ SYSCALL_DEFINE5(execveat, const char __user *const __user *, envp, int, flags) { - int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0; - struct filename *name = getname_flags(filename, lookup_flags, NULL); - - return do_execveat(fd, name, argv, envp, flags, NULL); + return do_execveat(fd, filename, argv, envp, flags); } /* @@ -2017,7 +2084,7 @@ COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename, const char __user *const __user *, argv, const char __user *const __user *, envp) { - return do_execveat(AT_FDCWD, getname(filename), argv, envp, 0, NULL); + return do_execveat(AT_FDCWD, filename, argv, envp, 0); } COMPAT_SYSCALL_DEFINE5(execveat, int, fd, @@ -2026,9 +2093,6 @@ COMPAT_SYSCALL_DEFINE5(execveat, int, fd, const char __user *const __user *, envp, int, flags) { - int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0; - struct filename *name = getname_flags(filename, lookup_flags, NULL); - - return do_execveat(fd, name, argv, envp, flags, NULL); + return do_execveat(fd, filename, argv, envp, flags); } #endif /* CONFIG_X86_X32 */ diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h index bed702e4b1fbd9..1e61c980c16354 100644 --- a/include/linux/binfmts.h +++ b/include/linux/binfmts.h @@ -134,9 +134,7 @@ int copy_string_kernel(const char *arg, struct linux_binprm *bprm); extern void set_binfmt(struct linux_binfmt *new); extern ssize_t read_code(struct file *, unsigned long, loff_t, size_t); -int do_execveat(int fd, struct filename *filename, - const char __user *const __user *__argv, - const char __user *const __user *__envp, - int flags, struct file *file); +int kernel_execveat(int fd, const char *filename, const char *const *argv, + const char *const *envp, int flags, struct file *file); #endif /* _LINUX_BINFMTS_H */ diff --git a/init/main.c b/init/main.c index 838950ea7bca22..33de235dc2aa00 100644 --- a/init/main.c +++ b/init/main.c @@ -1329,10 +1329,8 @@ static int run_init_process(const char *init_filename) pr_debug(" with environment:\n"); for (p = envp_init; *p; p++) pr_debug(" %s\n", *p); - return do_execveat(AT_FDCWD, getname_kernel(init_filename), - (const char __user *const __user *)argv_init, - (const char __user *const __user *)envp_init, - 0, NULL); + return kernel_execveat(AT_FDCWD, init_filename, argv_init, envp_init, 0, + NULL); } static int try_to_run_init_process(const char *init_filename) diff --git a/kernel/umh.c b/kernel/umh.c index 7aa9a5817582ca..1284823dbad338 100644 --- a/kernel/umh.c +++ b/kernel/umh.c @@ -103,11 +103,9 @@ static int call_usermodehelper_exec_async(void *data) commit_creds(new); sub_info->pid = task_pid_nr(current); - retval = do_execveat(AT_FDCWD, - sub_info->path ? getname_kernel(sub_info->path) : NULL, - (const char __user *const __user *)sub_info->argv, - (const char __user *const __user *)sub_info->envp, - 0, sub_info->file); + retval = kernel_execveat(AT_FDCWD, sub_info->path, + (const char *const *)sub_info->argv, + (const char *const *)sub_info->envp, 0, sub_info->file); if (sub_info->file && !retval) current->flags |= PF_UMH; out: From patchwork Mon Jun 15 13:00:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11604879 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 49AA592A for ; Mon, 15 Jun 2020 13:01:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 30A56207D4 for ; Mon, 15 Jun 2020 13:01:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Qo5IGkkz" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730109AbgFONBA (ORCPT ); Mon, 15 Jun 2020 09:01:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52414 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730251AbgFONA6 (ORCPT ); Mon, 15 Jun 2020 09:00:58 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A280DC061A0E; Mon, 15 Jun 2020 06:00:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=T94kCvjMg3POOYY9QZ5B+bKnsinmf9rCUNlS0Naq4B0=; b=Qo5IGkkztcUZUo+cF8SPeORX9i w8KjM/VC9s4RMbj4LN1fKVtGCejc53i0Zu2X7+dZHUKqbl+/UWNGou0bWdNaQSGZGFBALkNZyyX7G 7WPcNWmdxBXgCdcQmbNo4w+COAtvJ909XyC6k/F9jHQD/7PTa4oq2W1vPCOQ0q/U7pcIct/SwXOFK ttpKACNil9TDb9+ef+c4u10g1xvHGoDSCuYvcugulrM6h5bvWrzi4gpMUu3jqFiIt+7jLRAhrE1wo AYbI592N/mkwbu7osPGGfCrVJQGOe+sP14GCKFKsGMmY+XEQIT5qRRum69TNwcvDRsf4IHCkpK76+ SpOrojPQ==; Received: from 195-192-102-148.dyn.cablelink.at ([195.192.102.148] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jkojK-00081b-G3; Mon, 15 Jun 2020 13:00:51 +0000 From: Christoph Hellwig To: Al Viro Cc: Arnd Bergmann , Luis Chamberlain , linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 6/6] kernel: add a kernel_wait helper Date: Mon, 15 Jun 2020 15:00:32 +0200 Message-Id: <20200615130032.931285-7-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200615130032.931285-1-hch@lst.de> References: <20200615130032.931285-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Add a helper that waits for a pid and stores the status in the passed in kernel pointer. Use it to fix the usage of kernel_wait4 in call_usermodehelper_exec_sync that only happens to work due to the implicit set_fs(KERNEL_DS) for kernel threads. Signed-off-by: Christoph Hellwig --- include/linux/sched/task.h | 1 + kernel/exit.c | 16 ++++++++++++++++ kernel/umh.c | 29 ++++------------------------- 3 files changed, 21 insertions(+), 25 deletions(-) diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h index 38359071236ad7..a80007df396e95 100644 --- a/include/linux/sched/task.h +++ b/include/linux/sched/task.h @@ -102,6 +102,7 @@ struct task_struct *fork_idle(int); struct mm_struct *copy_init_mm(void); extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); extern long kernel_wait4(pid_t, int __user *, int, struct rusage *); +int kernel_wait(pid_t pid, int *stat); extern void free_task(struct task_struct *tsk); diff --git a/kernel/exit.c b/kernel/exit.c index 727150f2810338..fd598846df0b17 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -1626,6 +1626,22 @@ long kernel_wait4(pid_t upid, int __user *stat_addr, int options, return ret; } +int kernel_wait(pid_t pid, int *stat) +{ + struct wait_opts wo = { + .wo_type = PIDTYPE_PID, + .wo_pid = find_get_pid(pid), + .wo_flags = WEXITED, + }; + int ret; + + ret = do_wait(&wo); + if (ret > 0 && wo.wo_stat) + *stat = wo.wo_stat; + put_pid(wo.wo_pid); + return ret; +} + SYSCALL_DEFINE4(wait4, pid_t, upid, int __user *, stat_addr, int, options, struct rusage __user *, ru) { diff --git a/kernel/umh.c b/kernel/umh.c index 1284823dbad338..6fd948e478bec4 100644 --- a/kernel/umh.c +++ b/kernel/umh.c @@ -126,37 +126,16 @@ static void call_usermodehelper_exec_sync(struct subprocess_info *sub_info) { pid_t pid; - /* If SIGCLD is ignored kernel_wait4 won't populate the status. */ + /* If SIGCLD is ignored do_wait won't populate the status. */ kernel_sigaction(SIGCHLD, SIG_DFL); pid = kernel_thread(call_usermodehelper_exec_async, sub_info, SIGCHLD); - if (pid < 0) { + if (pid < 0) sub_info->retval = pid; - } else { - int ret = -ECHILD; - /* - * Normally it is bogus to call wait4() from in-kernel because - * wait4() wants to write the exit code to a userspace address. - * But call_usermodehelper_exec_sync() always runs as kernel - * thread (workqueue) and put_user() to a kernel address works - * OK for kernel threads, due to their having an mm_segment_t - * which spans the entire address space. - * - * Thus the __user pointer cast is valid here. - */ - kernel_wait4(pid, (int __user *)&ret, 0, NULL); - - /* - * If ret is 0, either call_usermodehelper_exec_async failed and - * the real error code is already in sub_info->retval or - * sub_info->retval is 0 anyway, so don't mess with it then. - */ - if (ret) - sub_info->retval = ret; - } + else + kernel_wait(pid, &sub_info->retval); /* Restore default kernel sig handler */ kernel_sigaction(SIGCHLD, SIG_IGN); - umh_complete(sub_info); }