From patchwork Tue Jul 18 22:33:19 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Garnier X-Patchwork-Id: 9850033 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1EB8060392 for ; Tue, 18 Jul 2017 22:35:52 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 09FDD285B7 for ; Tue, 18 Jul 2017 22:35:52 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F1B7B285CD; Tue, 18 Jul 2017 22:35:51 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, RCVD_IN_DNSWL_MED, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id D720F285B7 for ; Tue, 18 Jul 2017 22:35:50 +0000 (UTC) Received: (qmail 26485 invoked by uid 550); 18 Jul 2017 22:34:36 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 26337 invoked from network); 18 Jul 2017 22:34:34 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=UpMEsq8AofDPyhtX1fiCHZciKW2pc/cVSIecBulyr4E=; b=tpGdBZj3ljXYWl34a0u6CUYSUCfU+WY62K0NvYIm0R7zpG1AOKm5mwUUd/QU2kxQ8L xVMdCL/VLBLcLv+9Oqj44M1/6iF78xj5KFL+k+PeDAFTYRnzLY8wKVG05z1XpADsH8rF bR+j4KeNjB7z5pysXesrm8W9NiykCW02TCiQlkjoW/H3k3kwi2KA2+J4JUn9ss66kPmW mrzLnCOFKqjUiOY6FoGSu7ey/6hdfpV9GVPqtc60B13oOcMmvd28OXPboGKRs27aA0Iq DanVrKGN4Z2b983gWB3jpX8mcFFI+2/8jurPtoCsNaY2d5gJy3w9LKC2CmwPLLEDkPOb pixA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=UpMEsq8AofDPyhtX1fiCHZciKW2pc/cVSIecBulyr4E=; b=snEq2yE5Ql3dal2QFdYuz6ix34KubLLwvkJ7fQ5Z9lPETusCPkdc/nXSOuHl0xnjwG o5UeUGmAHJSIkXeaUZPWRp/VQ8rxhOQQuvrC7PmZ6yTC8dwaXL6pcbgBGBOvF2M2cQFO RuvAFFuP/7VrJv5u9ha8sfQ+bCXuqwfVsHVhUGVKZRoaE4Gigw4LoynlABrWuX6RiOv9 KJq8eH9KzPzYQWoOfj+IuAcoFz/ZQWofGmFwm6B/20OpTkwH3cxWe2NrKltGwzrjKg9S u/C4jrcEbdxiF6kE8iUxT0J3SPqd+GhlJUTVSQDHVlPsWjRo9R7XcrXbDbdeRRycb/Gz 3rsw== X-Gm-Message-State: AIVw112hAnoq9buD6UaWVMgkbxgXnH7A1YOF5lycZZCXroafdIRmY59V DTmVXVc72YZSPNAj X-Received: by 10.98.198.87 with SMTP id m84mr3970271pfg.122.1500417262244; Tue, 18 Jul 2017 15:34:22 -0700 (PDT) From: Thomas Garnier To: Herbert Xu , "David S . Miller" , Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , Peter Zijlstra , Josh Poimboeuf , Thomas Garnier , Arnd Bergmann , Matthias Kaehlcke , Boris Ostrovsky , Juergen Gross , Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Joerg Roedel , Andy Lutomirski , Borislav Petkov , "Kirill A . Shutemov" , Brian Gerst , Borislav Petkov , Christian Borntraeger , "Rafael J . Wysocki" , Len Brown , Pavel Machek , Tejun Heo , Christoph Lameter , Kees Cook , Paul Gortmaker , Chris Metcalf , "Paul E . McKenney" , Andrew Morton , Christopher Li , Dou Liyang , Masahiro Yamada , Daniel Borkmann , Markus Trippelsdorf , Peter Foley , Steven Rostedt , Tim Chen , Ard Biesheuvel , Catalin Marinas , Matthew Wilcox , Michal Hocko , Rob Landley , Jiri Kosina , "H . J . Lu" , Paul Bolle , Baoquan He , Daniel Micay Cc: x86@kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, kvm@vger.kernel.org, linux-pm@vger.kernel.org, linux-arch@vger.kernel.org, linux-sparse@vger.kernel.org, kernel-hardening@lists.openwall.com Date: Tue, 18 Jul 2017 15:33:19 -0700 Message-Id: <20170718223333.110371-9-thgarnie@google.com> X-Mailer: git-send-email 2.13.2.932.g7449e964c-goog In-Reply-To: <20170718223333.110371-1-thgarnie@google.com> References: <20170718223333.110371-1-thgarnie@google.com> Subject: [kernel-hardening] [RFC 08/22] x86/entry/64: Adapt assembly for PIE support X-Virus-Scanned: ClamAV using ClamSMTP Change the assembly code to use only relative references of symbols for the kernel to be PIE compatible. Position Independent Executable (PIE) support will allow to extended the KASLR randomization range below the -2G memory limit. Signed-off-by: Thomas Garnier --- arch/x86/entry/entry_64.S | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index a9a8027a6c0e..691c4755269b 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -195,12 +195,15 @@ entry_SYSCALL_64_fastpath: ja 1f /* return -ENOSYS (already in pt_regs->ax) */ movq %r10, %rcx + /* Ensures the call is position independent */ + leaq sys_call_table(%rip), %r11 + /* * This call instruction is handled specially in stub_ptregs_64. * It might end up jumping to the slow path. If it jumps, RAX * and all argument registers are clobbered. */ - call *sys_call_table(, %rax, 8) + call *(%r11, %rax, 8) .Lentry_SYSCALL_64_after_fastpath_call: movq %rax, RAX(%rsp) @@ -333,7 +336,8 @@ ENTRY(stub_ptregs_64) * RAX stores a pointer to the C function implementing the syscall. * IRQs are on. */ - cmpq $.Lentry_SYSCALL_64_after_fastpath_call, (%rsp) + leaq .Lentry_SYSCALL_64_after_fastpath_call(%rip), %r11 + cmpq %r11, (%rsp) jne 1f /* @@ -1109,7 +1113,8 @@ ENTRY(error_entry) movl %ecx, %eax /* zero extend */ cmpq %rax, RIP+8(%rsp) je .Lbstep_iret - cmpq $.Lgs_change, RIP+8(%rsp) + leaq .Lgs_change(%rip), %rcx + cmpq %rcx, RIP+8(%rsp) jne .Lerror_entry_done /* @@ -1324,10 +1329,10 @@ ENTRY(nmi) * resume the outer NMI. */ - movq $repeat_nmi, %rdx + leaq repeat_nmi(%rip), %rdx cmpq 8(%rsp), %rdx ja 1f - movq $end_repeat_nmi, %rdx + leaq end_repeat_nmi(%rip), %rdx cmpq 8(%rsp), %rdx ja nested_nmi_out 1: @@ -1381,7 +1386,8 @@ nested_nmi: pushq %rdx pushfq pushq $__KERNEL_CS - pushq $repeat_nmi + leaq repeat_nmi(%rip), %rdx + pushq %rdx /* Put stack back */ addq $(6*8), %rsp @@ -1419,7 +1425,9 @@ first_nmi: addq $8, (%rsp) /* Fix up RSP */ pushfq /* RFLAGS */ pushq $__KERNEL_CS /* CS */ - pushq $1f /* RIP */ + pushq %rax /* Support Position Independent Code */ + leaq 1f(%rip), %rax /* RIP */ + xchgq %rax, (%rsp) /* Restore RAX, put 1f */ INTERRUPT_RETURN /* continues at repeat_nmi below */ 1: #endif