From: Thomas Garnier <thgarnie@google.com> To: "Herbert Xu" <herbert@gondor.apana.org.au>, "David S . Miller" <davem@davemloft.net>, "Thomas Gleixner" <tglx@linutronix.de>, "Ingo Molnar" <mingo@redhat.com>, "H . Peter Anvin" <hpa@zytor.com>, "Peter Zijlstra" <peterz@infradead.org>, "Josh Poimboeuf" <jpoimboe@redhat.com>, "Thomas Garnier" <thgarnie@google.com>, "Arnd Bergmann" <arnd@arndb.de>, "Matthias Kaehlcke" <mka@chromium.org>, "Boris Ostrovsky" <boris.ostrovsky@oracle.com>, "Juergen Gross" <jgross@suse.com>, "Paolo Bonzini" <pbonzini@redhat.com>, "Radim Krčmář" <rkrcmar@redhat.com>, "Joerg Roedel" <joro@8bytes.org>, "Andy Lutomirski" <luto@kernel.org>, "Borislav Petkov" <bp@alien8.de>, "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>, "Brian Gerst" <brgerst@gmail.com>, "Borislav Petkov" <bp@suse.de>, "Christian Borntraeger" <borntraeger@de.ibm.com>, "Rafael J . Wysocki" <rjw@rjwysocki.net> Cc: linux-arch@vger.kernel.org, kvm@vger.kernel.org, linux-pm@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, linux-sparse@vger.kernel.org, linux-crypto@vger.kernel.org, kernel-hardening@lists.openwall.com, xen-devel@lists.xenproject.org Subject: [RFC 08/22] x86/entry/64: Adapt assembly for PIE support Date: Tue, 18 Jul 2017 15:33:19 -0700 [thread overview] Message-ID: <20170718223333.110371-9-thgarnie@google.com> (raw) In-Reply-To: <20170718223333.110371-1-thgarnie@google.com> 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 <thgarnie@google.com> --- 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 -- 2.13.2.932.g7449e964c-goog _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel
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From: Thomas Garnier <thgarnie@google.com> To: "Herbert Xu" <herbert@gondor.apana.org.au>, "David S . Miller" <davem@davemloft.net>, "Thomas Gleixner" <tglx@linutronix.de>, "Ingo Molnar" <mingo@redhat.com>, "H . Peter Anvin" <hpa@zytor.com>, "Peter Zijlstra" <peterz@infradead.org>, "Josh Poimboeuf" <jpoimboe@redhat.com>, "Thomas Garnier" <thgarnie@google.com>, "Arnd Bergmann" <arnd@arndb.de>, "Matthias Kaehlcke" <mka@chromium.org>, "Boris Ostrovsky" <boris.ostrovsky@oracle.com>, "Juergen Gross" <jgross@suse.com>, "Paolo Bonzini" <pbonzini@redhat.com>, "Radim Krčmář" <rkrcmar@redhat.com>, "Joerg Roedel" <joro@8bytes.org>, "Andy Lutomirski" <luto@kernel.org>, "Borislav Petkov" <bp@alien8.de>, "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>, "Brian Gerst" <brgerst@gmail.com>, "Borislav Petkov" <bp@suse.de>, "Christian Borntraeger" <borntraeger@de.ibm.com>, "Rafael J . Wysocki" <rjw@rjwysocki.net>, "Len Brown" <len.brown@intel.com>, "Pavel Machek" <pavel@ucw.cz>, "Tejun Heo" <tj@kernel.org>, "Christoph Lameter" <cl@linux.com>, "Kees Cook" <keescook@chromium.org>, "Paul Gortmaker" <paul.gortmaker@windriver.com>, "Chris Metcalf" <cmetcalf@mellanox.com>, "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>, "Andrew Morton" <akpm@linux-foundation.org>, "Christopher Li" <sparse@chrisli.org>, "Dou Liyang" <douly.fnst@cn.fujitsu.com>, "Masahiro Yamada" <yamada.masahiro@socionext.com>, "Daniel Borkmann" <daniel@iogearbox.net>, "Markus Trippelsdorf" <markus@trippelsdorf.de>, "Peter Foley" <pefoley2@pefoley.com>, "Steven Rostedt" <rostedt@goodmis.org>, "Tim Chen" <tim.c.chen@linux.intel.com>, "Ard Biesheuvel" <ard.biesheuvel@linaro.org>, "Catalin Marinas" <catalin.marinas@arm.com>, "Matthew Wilcox" <mawilcox@microsoft.com>, "Michal Hocko" <mhocko@suse.com>, "Rob Landley" <rob@landley.net>, "Jiri Kosina" <jkosina@suse.cz>, "H . J . Lu" <hjl.tools@gmail.com>, "Paul Bolle" <pebolle@tiscali.nl>, "Baoquan He" <bhe@redhat.com>, "Daniel Micay" <danielmicay@gmail.com> 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 Subject: [kernel-hardening] [RFC 08/22] x86/entry/64: Adapt assembly for PIE support Date: Tue, 18 Jul 2017 15:33:19 -0700 [thread overview] Message-ID: <20170718223333.110371-9-thgarnie@google.com> (raw) In-Reply-To: <20170718223333.110371-1-thgarnie@google.com> 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 <thgarnie@google.com> --- 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 -- 2.13.2.932.g7449e964c-goog
next prev parent reply other threads:[~2017-07-18 22:33 UTC|newest] Thread overview: 151+ messages / expand[flat|nested] mbox.gz Atom feed top 2017-07-18 22:33 x86: PIE support and option to extend KASLR randomization Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 01/22] x86/crypto: Adapt assembly for PIE support Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` Thomas Garnier 2017-07-18 22:33 ` [RFC 02/22] x86: Use symbol name on bug table " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 03/22] x86: Use symbol name in jump " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 04/22] x86: Add macro to get symbol address " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 05/22] xen: Adapt assembly " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 06/22] kvm: " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-19 2:49 ` Brian Gerst 2017-07-19 2:49 ` Brian Gerst 2017-07-19 2:49 ` [kernel-hardening] " Brian Gerst 2017-07-19 15:40 ` Thomas Garnier 2017-07-19 15:40 ` [kernel-hardening] " Thomas Garnier 2017-07-19 22:27 ` H. Peter Anvin 2017-07-19 22:27 ` H. Peter Anvin 2017-07-19 22:27 ` [kernel-hardening] " H. Peter Anvin 2017-07-19 22:44 ` Thomas Garnier 2017-07-19 22:44 ` [kernel-hardening] " Thomas Garnier 2017-07-19 22:44 ` Thomas Garnier 2017-07-19 22:58 ` Ard Biesheuvel 2017-07-19 22:58 ` Ard Biesheuvel 2017-07-19 22:58 ` [kernel-hardening] " Ard Biesheuvel 2017-07-19 23:47 ` H. Peter Anvin 2017-07-19 23:47 ` H. Peter Anvin 2017-07-19 23:47 ` H. Peter Anvin 2017-07-19 23:47 ` H. Peter Anvin 2017-07-19 23:47 ` H. Peter Anvin 2017-07-19 23:47 ` H. Peter Anvin 2017-07-19 23:47 ` H. Peter Anvin 2017-07-19 15:40 ` Thomas Garnier 2017-07-18 22:33 ` [RFC 07/22] x86: relocate_kernel - " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-19 22:58 ` H. Peter Anvin 2017-07-19 22:58 ` H. Peter Anvin 2017-07-19 22:58 ` [kernel-hardening] " H. Peter Anvin 2017-07-19 23:23 ` Thomas Garnier 2017-07-19 23:23 ` [kernel-hardening] " Thomas Garnier 2017-07-19 23:23 ` Thomas Garnier 2017-07-18 22:33 ` Thomas Garnier [this message] 2017-07-18 22:33 ` [kernel-hardening] [RFC 08/22] x86/entry/64: " Thomas Garnier 2017-07-18 22:33 ` [RFC 09/22] x86: pm-trace - " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 10/22] x86/CPU: " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 11/22] x86/acpi: " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 12/22] x86/boot/64: " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 13/22] x86/power/64: " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-19 18:41 ` Pavel Machek 2017-07-19 18:41 ` [kernel-hardening] " Pavel Machek 2017-07-19 18:41 ` Pavel Machek 2017-07-18 22:33 ` [RFC 14/22] x86/paravirt: " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 15/22] x86/boot/64: Use _text in a global " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 16/22] x86/percpu: Adapt percpu " Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-19 3:08 ` Brian Gerst 2017-07-19 3:08 ` [kernel-hardening] " Brian Gerst 2017-07-19 18:26 ` Thomas Garnier 2017-07-19 18:26 ` Thomas Garnier 2017-07-19 18:26 ` [kernel-hardening] " Thomas Garnier 2017-07-19 23:33 ` H. Peter Anvin 2017-07-19 23:33 ` H. Peter Anvin 2017-07-19 23:33 ` [kernel-hardening] " H. Peter Anvin 2017-07-20 2:21 ` H. Peter Anvin 2017-07-20 2:21 ` H. Peter Anvin 2017-07-20 2:21 ` [kernel-hardening] " H. Peter Anvin 2017-07-20 3:03 ` H. Peter Anvin 2017-07-20 3:03 ` H. Peter Anvin 2017-07-20 3:03 ` [kernel-hardening] " H. Peter Anvin 2017-07-20 14:26 ` Thomas Garnier 2017-07-20 14:26 ` [kernel-hardening] " Thomas Garnier 2017-08-02 16:42 ` Thomas Garnier 2017-08-02 16:42 ` Thomas Garnier 2017-08-02 16:42 ` [kernel-hardening] " Thomas Garnier 2017-08-02 16:56 ` Kees Cook 2017-08-02 16:56 ` [kernel-hardening] " Kees Cook 2017-08-02 18:05 ` Thomas Garnier 2017-08-02 18:05 ` [kernel-hardening] " Thomas Garnier 2017-08-02 18:05 ` Thomas Garnier 2017-08-02 16:56 ` Kees Cook 2017-07-20 14:26 ` Thomas Garnier 2017-07-19 3:08 ` Brian Gerst 2017-07-18 22:33 ` [RFC 17/22] compiler: Option to default to hidden symbols Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 18/22] x86/relocs: Handle DYN relocations for PIE support Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 19/22] x86/pie: Add option to build the kernel as PIE for x86_64 Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-18 22:33 ` [RFC 20/22] x86/relocs: Add option to generate 64-bit relocations Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-19 22:33 ` H. Peter Anvin 2017-07-19 22:33 ` H. Peter Anvin 2017-07-19 22:33 ` [kernel-hardening] " H. Peter Anvin 2017-07-19 22:47 ` Thomas Garnier 2017-07-19 22:47 ` Thomas Garnier 2017-07-19 22:47 ` [kernel-hardening] " Thomas Garnier 2017-07-19 23:08 ` H. Peter Anvin 2017-07-19 23:08 ` [kernel-hardening] " H. Peter Anvin 2017-07-19 23:25 ` Thomas Garnier 2017-07-19 23:25 ` [kernel-hardening] " Thomas Garnier 2017-07-19 23:45 ` H. Peter Anvin 2017-07-19 23:45 ` H. Peter Anvin 2017-07-19 23:45 ` H. Peter Anvin 2017-07-19 23:45 ` H. Peter Anvin 2017-07-19 23:45 ` H. Peter Anvin 2017-07-19 23:45 ` H. Peter Anvin 2017-07-19 23:45 ` H. Peter Anvin 2017-07-19 23:25 ` Thomas Garnier 2017-07-19 23:08 ` H. Peter Anvin 2017-07-18 22:33 ` [RFC 21/22] x86/module: Add support for mcmodel large and PLTs Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-19 1:35 ` H. Peter Anvin 2017-07-19 1:35 ` H. Peter Anvin 2017-07-19 1:35 ` [kernel-hardening] " H. Peter Anvin 2017-07-19 3:59 ` Brian Gerst 2017-07-19 3:59 ` Brian Gerst 2017-07-19 3:59 ` [kernel-hardening] " Brian Gerst 2017-07-19 15:58 ` Thomas Garnier 2017-07-19 15:58 ` Thomas Garnier 2017-07-19 15:58 ` [kernel-hardening] " Thomas Garnier 2017-07-19 17:34 ` Brian Gerst 2017-07-19 17:34 ` [kernel-hardening] " Brian Gerst 2017-07-24 16:32 ` Thomas Garnier 2017-07-24 16:32 ` [kernel-hardening] " Thomas Garnier 2017-07-24 16:32 ` Thomas Garnier 2017-07-19 17:34 ` Brian Gerst 2017-07-18 22:33 ` [RFC 22/22] x86/kaslr: Add option to extend KASLR range from 1GB to 3GB Thomas Garnier 2017-07-18 22:33 ` [kernel-hardening] " Thomas Garnier 2017-07-19 12:10 ` Baoquan He 2017-07-19 12:10 ` [kernel-hardening] " Baoquan He 2017-07-19 13:49 ` Baoquan He 2017-07-19 13:49 ` Baoquan He 2017-07-19 13:49 ` [kernel-hardening] " Baoquan He 2017-07-19 12:10 ` Baoquan He 2017-07-19 14:08 ` x86: PIE support and option to extend KASLR randomization Christopher Lameter 2017-07-19 14:08 ` [kernel-hardening] " Christopher Lameter 2017-07-19 19:21 ` Kees Cook 2017-07-19 19:21 ` Kees Cook 2017-07-19 19:21 ` [kernel-hardening] " Kees Cook 2017-07-19 14:08 ` Christopher Lameter
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