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2017-03-20x86/arch_prctl/64: Rename do_arch_prctl() to do_arch_prctl_64()Kyle Huey
In order to introduce new arch_prctls that are not 64 bit only, rename the existing 64 bit implementation to do_arch_prctl_64(). Also rename the second argument of that function from 'addr' to 'arg2', because it will no longer always be an address. Signed-off-by: Kyle Huey <khuey@kylehuey.com> Reviewed-by: Andy Lutomirski <luto@kernel.org> Cc: Grzegorz Andrejczuk <grzegorz.andrejczuk@intel.com> Cc: kvm@vger.kernel.org Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: linux-kselftest@vger.kernel.org Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Robert O'Callahan <robert@ocallahan.org> Cc: Richard Weinberger <richard@nod.at> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Len Brown <len.brown@intel.com> Cc: Shuah Khan <shuah@kernel.org> Cc: user-mode-linux-devel@lists.sourceforge.net Cc: Jeff Dike <jdike@addtoit.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: user-mode-linux-user@lists.sourceforge.net Cc: David Matlack <dmatlack@google.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Dmitry Safonov <dsafonov@virtuozzo.com> Cc: linux-fsdevel@vger.kernel.org Cc: Paolo Bonzini <pbonzini@redhat.com> Link: http://lkml.kernel.org/r/20170320081628.18952-5-khuey@kylehuey.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/task_stack.h> We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task_stack.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-03Merge branch 'x86-vdso-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 vdso updates from Ingo Molnar: "The main changes in this cycle centered around adding support for 32-bit compatible C/R of the vDSO on 64-bit kernels, by Dmitry Safonov" * 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vdso: Use CONFIG_X86_X32_ABI to enable vdso prctl x86/vdso: Only define map_vdso_randomized() if CONFIG_X86_64 x86/vdso: Only define prctl_map_vdso() if CONFIG_CHECKPOINT_RESTORE x86/signal: Add SA_{X32,IA32}_ABI sa_flags x86/ptrace: Down with test_thread_flag(TIF_IA32) x86/coredump: Use pr_reg size, rather that TIF_IA32 flag x86/arch_prctl/vdso: Add ARCH_MAP_VDSO_* x86/vdso: Replace calculate_addr in map_vdso() with addr x86/vdso: Unmap vdso blob on vvar mapping failure
2016-09-15x86/asm: Move the thread_info::status field to thread_structAndy Lutomirski
Because sched.h and thread_info.h are a tangled mess, I turned in_compat_syscall() into a macro. If we had current_thread_struct() or similar and we could use it from thread_info.h, then this would be a bit cleaner. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jann Horn <jann@thejh.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/ccc8a1b2f41f9c264a41f771bb4a6539a642ad72.1473801993.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-14x86/ptrace: Down with test_thread_flag(TIF_IA32)Dmitry Safonov
As the task isn't executing at the moment of {GET,SET}REGS, return regset that corresponds to code selector, rather than value of TIF_IA32 flag. I.e. if we ptrace i386 elf binary that has just changed it's code selector to __USER_CS, than GET_REGS will return full x86_64 register set. Note, that this will work only if application has changed it's CS. If the application does 32-bit syscall with __USER_CS, ptrace will still return 64-bit register set. Which might be still confusing for tools that expect TS_COMPACT to be exposed [1, 2]. So this this change should make PTRACE_GETREGSET more reliable and this will be another step to drop TIF_{IA32,X32} flags. [1]: https://sourceforge.net/p/strace/mailman/message/30471411/ [2]: https://lkml.org/lkml/2012/1/18/320 Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com> Cc: 0x7f454c46@gmail.com Cc: oleg@redhat.com Cc: linux-mm@kvack.org Cc: luto@kernel.org Cc: Pedro Alves <palves@redhat.com> Cc: gorcunov@openvz.org Cc: xemul@virtuozzo.com Link: http://lkml.kernel.org/r/20160905133308.28234-6-dsafonov@virtuozzo.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-08Merge branch 'x86/mm' into x86/asm, to unify the two branches for simplicityIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18x86/dumpstack: Fix x86_32 kernel_stack_pointer() previous stack accessJosh Poimboeuf
On x86_32, when an interrupt happens from kernel space, SS and SP aren't pushed and the existing stack is used. So pt_regs is effectively two words shorter, and the previous stack pointer is normally the memory after the shortened pt_regs, aka '&regs->sp'. But in the rare case where the interrupt hits right after the stack pointer has been changed to point to an empty stack, like for example when call_on_stack() is used, the address immediately after the shortened pt_regs is no longer on the stack. In that case, instead of '&regs->sp', the previous stack pointer should be retrieved from the beginning of the current stack page. kernel_stack_pointer() wants to do that, but it forgets to dereference the pointer. So instead of returning a pointer to the previous stack, it returns a pointer to the beginning of the current stack. Note that it's probably outside of kernel_stack_pointer()'s scope to be switching stacks at all. The x86_64 version of this function doesn't do it, and it would be better for the caller to do it if necessary. But that's a patch for another day. This just fixes the original intent. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 0788aa6a23cb ("x86: Prepare removal of previous_esp from i386 thread_info structure") Link: http://lkml.kernel.org/r/472453d6e9f6a2d4ab16aaed4935f43117111566.1471535549.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10x86: Apply more __ro_after_init and constKees Cook
Guided by grsecurity's analogous __read_only markings in arch/x86, this applies several uses of __ro_after_init to structures that are only updated during __init, and const for some structures that are never updated. Additionally extends __init markings to some functions that are only used during __init, and cleans up some missing C99 style static initializers. Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brad Spengler <spender@grsecurity.net> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Brown <david.brown@linaro.org> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Emese Revfy <re.emese@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathias Krause <minipli@googlemail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: PaX Team <pageexec@freemail.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20160808232906.GA29731@www.outflux.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-27x86/ptrace: Stop setting TS_COMPAT in ptrace codeAndy Lutomirski
Setting TS_COMPAT in ptrace is wrong: if we happen to do it during syscall entry, then we'll confuse seccomp and audit. (The former isn't a security problem: seccomp is currently entirely insecure if a malicious ptracer is attached.) As a minimal fix, this patch adds a new flag TS_I386_REGS_POKED that handles the ptrace special case. Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Pedro Alves <palves@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/5383ebed38b39fa37462139e337aff7f2314d1ca.1469599803.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-20x86/fsgsbase/64: Use TASK_SIZE_MAX for FSBASE/GSBASE upper limitsAndy Lutomirski
The GSBASE upper limit exists to prevent user code from confusing the paranoid idtentry path. The FSBASE upper limit is just for consistency. There's no need to enforce a smaller limit for 32-bit tasks. Just use TASK_SIZE_MAX. This simplifies the logic and will save a few bytes of code. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/5357f2fe0f103eabf005773b70722451eab09a89.1462897104.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-29x86/asm/64: Rename thread_struct's fs and gs to fsbase and gsbaseAndy Lutomirski
Unlike ds and es, these are base addresses, not selectors. Rename them so their meaning is more obvious. On x86_32, the field is still called fs. Fixing that could make sense as a future cleanup. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/69a18a51c4cba0ce29a241e570fc618ad721d908.1461698311.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-29x86/arch_prctl/64: Remove FSBASE/GSBASE < 4G optimizationAndy Lutomirski
As far as I know, the optimization doesn't work on any modern distro because modern distros use high addresses for ASLR. Remove it. The ptrace code was either wrong or very strange, but the behavior with this patch should be essentially identical to the behavior without this patch unless user code goes out of its way to mislead ptrace. On newer CPUs, once the FSGSBASE instructions are enabled, we won't want to use the optimized variant anyway. This isn't actually much of a performance regression, it has no effect on normal dynamically linked programs, and it's a considerably simplification. It also removes some nasty special cases from code that is already way too full of special cases for comfort. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/dd1599b08866961dba9d2458faa6bbd7fba471d7.1461698311.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-19x86/entry: Rename is_{ia32,x32}_task() to in_{ia32,x32}_syscall()Dmitry Safonov
The is_ia32_task()/is_x32_task() function names are a big misnomer: they suggests that the compat-ness of a system call is a task property, which is not true, the compatness of a system call purely depends on how it was invoked through the system call layer. A task may call 32-bit and 64-bit and x32 system calls without changing any of its kernel visible state. This specific minomer is also actively dangerous, as it might cause kernel developers to use the wrong kind of security checks within system calls. So rename it to in_{ia32,x32}_syscall(). Suggested-by: Andy Lutomirski <luto@amacapital.net> Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com> [ Expanded the changelog. ] Acked-by: Andy Lutomirski <luto@kernel.org> Cc: 0x7f454c46@gmail.com Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: akpm@linux-foundation.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1460987025-30360-1-git-send-email-dsafonov@virtuozzo.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-12-29arch/x86/kernel/ptrace.c: Remove unused arg_offs_tablechengang@emindsoft.com.cn
The related warning from gcc 6.0: arch/x86/kernel/ptrace.c:127:18: warning: ‘arg_offs_table’ defined but not used [-Wunused-const-variable] static const int arg_offs_table[] = { ^~~~~~~~~~~~~~ Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Link: http://lkml.kernel.org/r/1451137798-28701-1-git-send-email-chengang@emindsoft.com.cn Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-07x86/entry: Move C entry and exit code to arch/x86/entry/common.cAndy Lutomirski
The entry and exit C helpers were confusingly scattered between ptrace.c and signal.c, even though they aren't specific to ptrace or signal handling. Move them together in a new file. This change just moves code around. It doesn't change anything. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/324d686821266544d8572423cc281f961da445f4.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06x86/compat: Factor out ia32 compat code from compat_arch_ptrace()Brian Gerst
Move the ia32-specific code in compat_arch_ptrace() into its own function. Signed-off-by: Brian Gerst <brgerst@gmail.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1434974121-32575-6-git-send-email-brgerst@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19x86/fpu: Factor out fpu/regset.h from fpu/internal.hIngo Molnar
Only a few places use the regset definitions, so factor them out. Also fix related header dependency assumptions. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19x86/fpu: Split out fpu/signal.h from fpu/internal.h for signal frame ↵Ingo Molnar
handling functions Most of the FPU does not use them, so split it out and include them in signal.c and ia32_signal.c Also fix header file dependency assumption in fpu/core.c. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19x86/fpu: Rename regset FPU register accessorsIngo Molnar
Rename regset accessors to prefix them with 'regset_', because we want to start using the 'fpregs_active' name elsewhere. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19x86/fpu: Rename fpu-internal.h to fpu/internal.hIngo Molnar
This unifies all the FPU related header files under a unified, hiearchical naming scheme: - asm/fpu/types.h: FPU related data types, needed for 'struct task_struct', widely included in almost all kernel code, and hence kept as small as possible. - asm/fpu/api.h: FPU related 'public' methods exported to other subsystems. - asm/fpu/internal.h: FPU subsystem internal methods - asm/fpu/xsave.h: XSAVE support internal methods (Also standardize the header guard in asm/fpu/internal.h.) Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19x86/fpu: Fix header file dependencies of fpu-internal.hIngo Molnar
Fix a minor header file dependency bug in asm/fpu-internal.h: it relies on i387.h but does not include it. All users of fpu-internal.h included it explicitly. Also remove unnecessary includes, to reduce compilation time. This also makes it easier to use it as a standalone header file for FPU internals, such as an upcoming C module in arch/x86/kernel/fpu/. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-23x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()'Andy Lutomirski
user_mode_vm() and user_mode() are now the same. Change all callers of user_mode_vm() to user_mode(). The next patch will remove the definition of user_mode_vm. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brad Spengler <spender@grsecurity.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/43b1f57f3df70df5a08b0925897c660725015554.1426728647.git.luto@kernel.org [ Merged to a more recent kernel. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-25x86/ptrace: Remove checks for TIF_IA32 when changing CS and SSAndy Lutomirski
The ability for modified CS and/or SS to be useful has nothing to do with TIF_IA32. Similarly, if there's an exploit involving changing CS or SS, it's exploitable with or without a TIF_IA32 check. So just delete the check. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Link: http://lkml.kernel.org/r/71c7ab36456855d11ae07edd4945a7dfe80f9915.1424822291.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-11-20x86, syscall: Fix _TIF_NOHZ handling in syscall_trace_enter_phase1Andy Lutomirski
TIF_NOHZ is 19 (i.e. _TIF_SYSCALL_TRACE | _TIF_NOTIFY_RESUME | _TIF_SINGLESTEP), not (1<<19). This code is involved in Dave's trinity lockup, but I don't see why it would cause any of the problems he's seeing, except inadvertently by causing a different path through entry_64.S's syscall handling. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Don Zickus <dzickus@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dave Jones <davej@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/a6cd3b60a3f53afb6e1c8081b0ec30ff19003dd7.1416434075.git.luto@amacapital.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-10-19Merge git://git.infradead.org/users/eparis/auditLinus Torvalds
Pull audit updates from Eric Paris: "So this change across a whole bunch of arches really solves one basic problem. We want to audit when seccomp is killing a process. seccomp hooks in before the audit syscall entry code. audit_syscall_entry took as an argument the arch of the given syscall. Since the arch is part of what makes a syscall number meaningful it's an important part of the record, but it isn't available when seccomp shoots the syscall... For most arch's we have a better way to get the arch (syscall_get_arch) So the solution was two fold: Implement syscall_get_arch() everywhere there is audit which didn't have it. Use syscall_get_arch() in the seccomp audit code. Having syscall_get_arch() everywhere meant it was a useless flag on the stack and we could get rid of it for the typical syscall entry. The other changes inside the audit system aren't grand, fixed some records that had invalid spaces. Better locking around the task comm field. Removing some dead functions and structs. Make some things static. Really minor stuff" * git://git.infradead.org/users/eparis/audit: (31 commits) audit: rename audit_log_remove_rule to disambiguate for trees audit: cull redundancy in audit_rule_change audit: WARN if audit_rule_change called illegally audit: put rule existence check in canonical order next: openrisc: Fix build audit: get comm using lock to avoid race in string printing audit: remove open_arg() function that is never used audit: correct AUDIT_GET_FEATURE return message type audit: set nlmsg_len for multicast messages. audit: use union for audit_field values since they are mutually exclusive audit: invalid op= values for rules audit: use atomic_t to simplify audit_serial() kernel/audit.c: use ARRAY_SIZE instead of sizeof/sizeof[0] audit: reduce scope of audit_log_fcaps audit: reduce scope of audit_net_id audit: arm64: Remove the audit arch argument to audit_syscall_entry arm64: audit: Add audit hook in syscall_trace_enter/exit() audit: x86: drop arch from __audit_syscall_entry() interface sparc: implement is_32bit_task sparc: properly conditionalize use of TIF_32BIT ...
2014-09-23ARCH: AUDIT: audit_syscall_entry() should not require the archEric Paris
We have a function where the arch can be queried, syscall_get_arch(). So rather than have every single piece of arch specific code use and/or duplicate syscall_get_arch(), just have the audit code use the syscall_get_arch() code. Based-on-patch-by: Richard Briggs <rgb@redhat.com> Signed-off-by: Eric Paris <eparis@redhat.com> Cc: linux-alpha@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-ia64@vger.kernel.org Cc: microblaze-uclinux@itee.uq.edu.au Cc: linux-mips@linux-mips.org Cc: linux@lists.openrisc.net Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: user-mode-linux-devel@lists.sourceforge.net Cc: linux-xtensa@linux-xtensa.org Cc: x86@kernel.org
2014-09-08x86: Split syscall_trace_enter into two phasesAndy Lutomirski
This splits syscall_trace_enter into syscall_trace_enter_phase1 and syscall_trace_enter_phase2. Only phase 2 has full pt_regs, and only phase 2 is permitted to modify any of pt_regs except for orig_ax. The intent is that phase 1 can be called from the syscall fast path. In this implementation, phase1 can handle any combination of TIF_NOHZ (RCU context tracking), TIF_SECCOMP, and TIF_SYSCALL_AUDIT, unless seccomp requests a ptrace event, in which case phase2 is forced. In principle, this could yield a big speedup for TIF_NOHZ as well as for TIF_SECCOMP if syscall exit work were similarly split up. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/2df320a600020fda055fccf2b668145729dd0c04.1409954077.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-09-08x86, entry: Only call user_exit if TIF_NOHZAndy Lutomirski
The RCU context tracking code requires that arch code call user_exit() on any entry into kernel code if TIF_NOHZ is set. This patch adds a check for TIF_NOHZ and a comment to the syscall entry tracing code. The main purpose of this patch is to make the code easier to follow: one can read the body of user_exit and of every function it calls without finding any explanation of why it's called for traced syscalls but not for untraced syscalls. This makes it clear when user_exit() is necessary. Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/0b13e0e24ec0307d67ab7a23b58764f6b1270116.1409954077.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-09-08x86, x32, audit: Fix x32's AUDIT_ARCH wrt auditAndy Lutomirski
is_compat_task() is the wrong check for audit arch; the check should be is_ia32_task(): x32 syscalls should be AUDIT_ARCH_X86_64, not AUDIT_ARCH_I386. CONFIG_AUDITSYSCALL is currently incompatible with x32, so this has no visible effect. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/a0138ed8c709882aec06e4acc30bfa9b623b8717.1409954077.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-09-03seccomp,x86,arm,mips,s390: Remove nr parameter from secure_computingAndy Lutomirski
The secure_computing function took a syscall number parameter, but it only paid any attention to that parameter if seccomp mode 1 was enabled. Rather than coming up with a kludge to get the parameter to work in mode 2, just remove the parameter. To avoid churn in arches that don't have seccomp filters (and may not even support syscall_get_nr right now), this leaves the parameter in secure_computing_strict, which is now a real function. For ARM, this is a bit ugly due to the fact that ARM conditionally supports seccomp filters. Fixing that would probably only be a couple of lines of code, but it should be coordinated with the audit maintainers. This will be a slight slowdown on some arches. The right fix is to pass in all of seccomp_data instead of trying to make just the syscall nr part be fast. This is a prerequisite for making two-phase seccomp work cleanly. Cc: Russell King <linux@arm.linux.org.uk> Cc: linux-arm-kernel@lists.infradead.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux-s390@vger.kernel.org Cc: x86@kernel.org Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Kees Cook <keescook@chromium.org>
2014-03-06x86: Keep thread_info on thread stack in x86_32Steven Rostedt
x86_64 uses a per_cpu variable kernel_stack to always point to the thread stack of current. This is where the thread_info is stored and is accessed from this location even when the irq or exception stack is in use. This removes the complexity of having to maintain the thread info on the stack when interrupts are running and having to copy the preempt_count and other fields to the interrupt stack. x86_32 uses the old method of copying the thread_info from the thread stack to the exception stack just before executing the exception. Having the two different requires #ifdefs and also the x86_32 way is a bit of a pain to maintain. By converting x86_32 to the same method of x86_64, we can remove #ifdefs, clean up the x86_32 code a little, and remove the overhead of the copy. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Brian Gerst <brgerst@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20110806012354.263834829@goodmis.org Link: http://lkml.kernel.org/r/20140206144321.852942014@goodmis.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-06x86: Prepare removal of previous_esp from i386 thread_info structureSteven Rostedt
The i386 thread_info contains a previous_esp field that is used to daisy chain the different stacks for dump_stack() (ie. irq, softirq, thread stacks). The goal is to eventual make i386 handling of thread_info the same as x86_64, which means that the thread_info will not be in the stack but as a per_cpu variable. We will no longer depend on thread_info being able to daisy chain different stacks as it will only exist in one location (the thread stack). By moving previous_esp to the end of thread_info and referencing it as an offset instead of using a thread_info field, this becomes a stepping stone to moving the thread_info. The offset to get to the previous stack is rather ugly in this patch, but this is only temporary and the prev_esp will be changed in the next commit. This commit is more for sanity checks of the change. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Robert Richter <rric@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20110806012353.891757693@goodmis.org Link: http://lkml.kernel.org/r/20140206144321.608754481@goodmis.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-07-09ptrace/x86: cleanup ptrace_set_debugreg()Oleg Nesterov
ptrace_set_debugreg() is trivial but looks horrible. Kill the unnecessary goto's and return's to cleanup the code. This matches ptrace_get_debugreg() which also needs the trivial whitespace cleanups. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jan Kratochvil <jan.kratochvil@redhat.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Prasad <prasad@linux.vnet.ibm.com> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09ptrace/x86: ptrace_write_dr7() should create bp if !disabledOleg Nesterov
Commit 24f1e32c60c4 ("hw-breakpoints: Rewrite the hw-breakpoints layer on top of perf events") introduced the minor regression. Before this commit PTRACE_POKEUSER DR7, enableDR0 PTRACE_POKEUSER DR0, address was perfectly valid, now PTRACE_POKEUSER(DR7) fails if DR0 was not previously initialized by PTRACE_POKEUSER(DR0). Change ptrace_write_dr7() to do ptrace_register_breakpoint(addr => 0) if !bp && !disabled. This fixes watchpoint-zeroaddr from ptrace-tests, see https://bugzilla.redhat.com/show_bug.cgi?id=660204. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reported-by: Jan Kratochvil <jan.kratochvil@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Michael Neuling <mikey@neuling.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Prasad <prasad@linux.vnet.ibm.com> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09ptrace/x86: introduce ptrace_register_breakpoint()Oleg Nesterov
No functional changes, preparation. Extract the "register breakpoint" code from ptrace_get_debugreg() into the new/generic helper, ptrace_register_breakpoint(). It will have more users. The patch also adds another simple helper, ptrace_fill_bp_fields(), to factor out the arch_bp_generic_fields() logic in register/modify. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jan Kratochvil <jan.kratochvil@redhat.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Prasad <prasad@linux.vnet.ibm.com> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09ptrace/x86: dont delay "disable" till second pass in ptrace_write_dr7()Oleg Nesterov
ptrace_write_dr7() skips ptrace_modify_breakpoint(disabled => true) unless second_pass, this buys nothing but complicates the code and means that we always do the main loop twice even if "disabled" was never true. The comment says: Don't unregister the breakpoints right-away, unless all register_user_hw_breakpoint() requests have succeeded. Firstly, we do not do register_user_hw_breakpoint(), it was removed by commit 24f1e32c60c4 ("hw-breakpoints: Rewrite the hw-breakpoints layer on top of perf events"). We are going to restore register_user_hw_breakpoint() (see the next patch) but this doesn't matter: after commit 44234adcdce3 ("hw-breakpoints: Modify breakpoints without unregistering them") perf_event_disable() can not hurt, hw_breakpoint_del() does not free the slot. Remove the "second_pass" check from the main loop and simplify the code. Since we have to check "bp != NULL" anyway, the patch also removes the same check in ptrace_modify_breakpoint() and moves the comment into ptrace_write_dr7(). With this patch the second pass is only needed to restore the saved old_dr7. This should never fail, so the patch adds WARN_ON() to catch the potential problems as Frederic suggested. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jan Kratochvil <jan.kratochvil@redhat.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Prasad <prasad@linux.vnet.ibm.com> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09ptrace/x86: simplify the "disable" logic in ptrace_write_dr7()Oleg Nesterov
ptrace_write_dr7() looks unnecessarily overcomplicated. We can factor out ptrace_modify_breakpoint() and do not do "continue" twice, just we need to pass the proper "disabled" argument to ptrace_modify_breakpoint(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jan Kratochvil <jan.kratochvil@redhat.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Prasad <prasad@linux.vnet.ibm.com> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09ptrace/x86: revert "hw_breakpoints: Fix racy access to ptrace breakpoints"Oleg Nesterov
This reverts commit 87dc669ba257 ("hw_breakpoints: Fix racy access to ptrace breakpoints"). The patch was fine but we can no longer race with SIGKILL after commit 9899d11f6544 ("ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL"), the __TASK_TRACED tracee can't be woken up and ->ptrace_bps[] can't go away. The patch only removes ptrace_get_breakpoints/ptrace_put_breakpoints and does a couple of "while at it" cleanups, it doesn't remove other changes from the reverted commit. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Jan Kratochvil <jan.kratochvil@redhat.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Prasad <prasad@linux.vnet.ibm.com> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-14x86: ptrace.c only needs export.h and not the full module.hPaul Gortmaker
Commit cb57a2b4cff7edf2a4e32c0163200e9434807e0a ("x86-32: Export kernel_stack_pointer() for modules") added an include of the module.h header in conjunction with adding an EXPORT_SYMBOL_GPL of kernel_stack_pointer. But module.h should be avoided for simple exports, since it in turn includes the world. Swap the module.h for export.h instead. Cc: Jiri Kosina <trivial@kernel.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Link: http://lkml.kernel.org/r/1360872842-28417-1-git-send-email-paul.gortmaker@windriver.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-12-03Merge branch 'rcu/next' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Conflicts: arch/x86/kernel/ptrace.c Pull the latest RCU tree from Paul E. McKenney: " The major features of this series are: 1. A first version of no-callbacks CPUs. This version prohibits offlining CPU 0, but only when enabled via CONFIG_RCU_NOCB_CPU=y. Relaxing this constraint is in progress, but not yet ready for prime time. These commits were posted to LKML at https://lkml.org/lkml/2012/10/30/724, and are at branch rcu/nocb. 2. Changes to SRCU that allows statically initialized srcu_struct structures. These commits were posted to LKML at https://lkml.org/lkml/2012/10/30/296, and are at branch rcu/srcu. 3. Restructuring of RCU's debugfs output. These commits were posted to LKML at https://lkml.org/lkml/2012/10/30/341, and are at branch rcu/tracing. 4. Additional CPU-hotplug/RCU improvements, posted to LKML at https://lkml.org/lkml/2012/10/30/327, and are at branch rcu/hotplug. Note that the commit eliminating __stop_machine() was judged to be too-high of risk, so is deferred to 3.9. 5. Changes to RCU's idle interface, most notably a new module parameter that redirects normal grace-period operations to their expedited equivalents. These were posted to LKML at https://lkml.org/lkml/2012/10/30/739, and are at branch rcu/idle. 6. Additional diagnostics for RCU's CPU stall warning facility, posted to LKML at https://lkml.org/lkml/2012/10/30/315, and are at branch rcu/stall. The most notable change reduces the default RCU CPU stall-warning time from 60 seconds to 21 seconds, so that it once again happens sooner than the softlockup timeout. 7. Documentation updates, which were posted to LKML at https://lkml.org/lkml/2012/10/30/280, and are at branch rcu/doc. A couple of late-breaking changes were posted at https://lkml.org/lkml/2012/11/16/634 and https://lkml.org/lkml/2012/11/16/547. 8. Miscellaneous fixes, which were posted to LKML at https://lkml.org/lkml/2012/10/30/309, along with a late-breaking change posted at Fri, 16 Nov 2012 11:26:25 -0800 with message-ID <20121116192625.GA447@linux.vnet.ibm.com>, but which lkml.org seems to have missed. These are at branch rcu/fixes. 9. Finally, a fix for an lockdep-RCU splat was posted to LKML at https://lkml.org/lkml/2012/11/7/486. This is at rcu/next. " Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-12-01Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU fix from Ingo Molnar: "Fix leaking RCU extended quiescent state, which might trigger warnings and mess up the extended quiescent state tracking logic into thinking that we are in "RCU user mode" while we aren't." * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rcu: Fix unrecovered RCU user mode in syscall_trace_leave()
2012-11-30context_tracking: New context tracking susbsystemFrederic Weisbecker
Create a new subsystem that probes on kernel boundaries to keep track of the transitions between level contexts with two basic initial contexts: user or kernel. This is an abstraction of some RCU code that use such tracking to implement its userspace extended quiescent state. We need to pull this up from RCU into this new level of indirection because this tracking is also going to be used to implement an "on demand" generic virtual cputime accounting. A necessary step to shutdown the tick while still accounting the cputime. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Gilad Ben-Yossef <gilad@benyossef.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> [ paulmck: fix whitespace error and email address. ] Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-20x86-32: Export kernel_stack_pointer() for modulesH. Peter Anvin
Modules, in particular oprofile (and possibly other similar tools) need kernel_stack_pointer(), so export it using EXPORT_SYMBOL_GPL(). Cc: Yang Wei <wei.yang@windriver.com> Cc: Robert Richter <robert.richter@amd.com> Cc: Jun Zhang <jun.zhang@intel.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20120912135059.GZ8285@erda.amd.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-11-20x86-32: Fix invalid stack address while in softirqRobert Richter
In 32 bit the stack address provided by kernel_stack_pointer() may point to an invalid range causing NULL pointer access or page faults while in NMI (see trace below). This happens if called in softirq context and if the stack is empty. The address at &regs->sp is then out of range. Fixing this by checking if regs and &regs->sp are in the same stack context. Otherwise return the previous stack pointer stored in struct thread_info. If that address is invalid too, return address of regs. BUG: unable to handle kernel NULL pointer dereference at 0000000a IP: [<c1004237>] print_context_stack+0x6e/0x8d *pde = 00000000 Oops: 0000 [#1] SMP Modules linked in: Pid: 4434, comm: perl Not tainted 3.6.0-rc3-oprofile-i386-standard-g4411a05 #4 Hewlett-Packard HP xw9400 Workstation/0A1Ch EIP: 0060:[<c1004237>] EFLAGS: 00010093 CPU: 0 EIP is at print_context_stack+0x6e/0x8d EAX: ffffe000 EBX: 0000000a ECX: f4435f94 EDX: 0000000a ESI: f4435f94 EDI: f4435f94 EBP: f5409ec0 ESP: f5409ea0 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 CR0: 8005003b CR2: 0000000a CR3: 34ac9000 CR4: 000007d0 DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 DR6: ffff0ff0 DR7: 00000400 Process perl (pid: 4434, ti=f5408000 task=f5637850 task.ti=f4434000) Stack: 000003e8 ffffe000 00001ffc f4e39b00 00000000 0000000a f4435f94 c155198c f5409ef0 c1003723 c155198c f5409f04 00000000 f5409edc 00000000 00000000 f5409ee8 f4435f94 f5409fc4 00000001 f5409f1c c12dce1c 00000000 c155198c Call Trace: [<c1003723>] dump_trace+0x7b/0xa1 [<c12dce1c>] x86_backtrace+0x40/0x88 [<c12db712>] ? oprofile_add_sample+0x56/0x84 [<c12db731>] oprofile_add_sample+0x75/0x84 [<c12ddb5b>] op_amd_check_ctrs+0x46/0x260 [<c12dd40d>] profile_exceptions_notify+0x23/0x4c [<c1395034>] nmi_handle+0x31/0x4a [<c1029dc5>] ? ftrace_define_fields_irq_handler_entry+0x45/0x45 [<c13950ed>] do_nmi+0xa0/0x2ff [<c1029dc5>] ? ftrace_define_fields_irq_handler_entry+0x45/0x45 [<c13949e5>] nmi_stack_correct+0x28/0x2d [<c1029dc5>] ? ftrace_define_fields_irq_handler_entry+0x45/0x45 [<c1003603>] ? do_softirq+0x4b/0x7f <IRQ> [<c102a06f>] irq_exit+0x35/0x5b [<c1018f56>] smp_apic_timer_interrupt+0x6c/0x7a [<c1394746>] apic_timer_interrupt+0x2a/0x30 Code: 89 fe eb 08 31 c9 8b 45 0c ff 55 ec 83 c3 04 83 7d 10 00 74 0c 3b 5d 10 73 26 3b 5d e4 73 0c eb 1f 3b 5d f0 76 1a 3b 5d e8 73 15 <8b> 13 89 d0 89 55 e0 e8 ad 42 03 00 85 c0 8b 55 e0 75 a6 eb cc EIP: [<c1004237>] print_context_stack+0x6e/0x8d SS:ESP 0068:f5409ea0 CR2: 000000000000000a ---[ end trace 62afee3481b00012 ]--- Kernel panic - not syncing: Fatal exception in interrupt V2: * add comments to kernel_stack_pointer() * always return a valid stack address by falling back to the address of regs Reported-by: Yang Wei <wei.yang@windriver.com> Cc: <stable@vger.kernel.org> Signed-off-by: Robert Richter <robert.richter@amd.com> Link: http://lkml.kernel.org/r/20120912135059.GZ8285@erda.amd.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Jun Zhang <jun.zhang@intel.com>
2012-10-27rcu: Fix unrecovered RCU user mode in syscall_trace_leave()Frederic Weisbecker
On x86-64 syscall exit, 3 non exclusive events may happen looping in the following order: 1) Check if we need resched for user preemption, if so call schedule_user() 2) Check if we have pending signals, if so call do_notify_resume() 3) Check if we do syscall tracing, if so call syscall_trace_leave() However syscall_trace_leave() has been written assuming it directly follows the syscall and forget about the above possible 1st and 2nd steps. Now schedule_user() and do_notify_resume() exit in RCU user mode because they have most chances to resume userspace immediately and this avoids an rcu_user_enter() call in the syscall fast path. So by the time we call syscall_trace_leave(), we may well be in RCU user mode. To fix this up, simply call rcu_user_exit() in the beginning of this function. This fixes some reported RCU uses in extended quiescent state. Reported-by: Dave Jones <davej@redhat.com> Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-10-01Merge branch 'x86-fpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/fpu update from Ingo Molnar: "The biggest change is the addition of the non-lazy (eager) FPU saving support model and enabling it on CPUs with optimized xsaveopt/xrstor FPU state saving instructions. There are also various Sparse fixes" Fix up trivial add-add conflict in arch/x86/kernel/traps.c * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, kvm: fix kvm's usage of kernel_fpu_begin/end() x86, fpu: remove cpu_has_xmm check in the fx_finit() x86, fpu: make eagerfpu= boot param tri-state x86, fpu: enable eagerfpu by default for xsaveopt x86, fpu: decouple non-lazy/eager fpu restore from xsave x86, fpu: use non-lazy fpu restore for processors supporting xsave lguest, x86: handle guest TS bit for lazy/non-lazy fpu host models x86, fpu: always use kernel_fpu_begin/end() for in-kernel FPU usage x86, kvm: use kernel_fpu_begin/end() in kvm_load/put_guest_fpu() x86, fpu: remove unnecessary user_fpu_end() in save_xstate_sig() x86, fpu: drop_fpu() before restoring new state from sigframe x86, fpu: Unify signal handling code paths for x86 and x86_64 kernels x86, fpu: Consolidate inline asm routines for saving/restoring fpu state x86, signal: Cleanup ifdefs and is_ia32, is_x32
2012-09-26x86: Syscall hooks for userspace RCU extended QSFrederic Weisbecker
Add syscall slow path hooks to notify syscall entry and exit on CPUs that want to support userspace RCU extended quiescent state. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Alessio Igor Bogani <abogani@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Gilad Ben Yossef <gilad@benyossef.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kevin Hilman <khilman@ti.com> Cc: Max Krasnyansky <maxk@qualcomm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-18x86, fpu: Unify signal handling code paths for x86 and x86_64 kernelsSuresh Siddha
Currently for x86 and x86_32 binaries, fpstate in the user sigframe is copied to/from the fpstate in the task struct. And in the case of signal delivery for x86_64 binaries, if the fpstate is live in the CPU registers, then the live state is copied directly to the user sigframe. Otherwise fpstate in the task struct is copied to the user sigframe. During restore, fpstate in the user sigframe is restored directly to the live CPU registers. Historically, different code paths led to different bugs. For example, x86_64 code path was not preemption safe till recently. Also there is lot of code duplication for support of new features like xsave etc. Unify signal handling code paths for x86 and x86_64 kernels. New strategy is as follows: Signal delivery: Both for 32/64-bit frames, align the core math frame area to 64bytes as needed by xsave (this where the main fpu/extended state gets copied to and excludes the legacy compatibility fsave header for the 32-bit [f]xsave frames). If the state is live, copy the register state directly to the user frame. If not live, copy the state in the thread struct to the user frame. And for 32-bit [f]xsave frames, construct the fsave header separately before the actual [f]xsave area. Signal return: As the 32-bit frames with [f]xstate has an additional 'fsave' header, copy everything back from the user sigframe to the fpstate in the task structure and reconstruct the fxstate from the 'fsave' header (Also user passed pointers may not be correctly aligned for any attempt to directly restore any partial state). At the next fpstate usage, everything will be restored to the live CPU registers. For all the 64-bit frames and the 32-bit fsave frame, restore the state from the user sigframe directly to the live CPU registers. 64-bit signals always restored the math frame directly, so we can expect the math frame pointer to be correctly aligned. For 32-bit fsave frames, there are no alignment requirements, so we can restore the state directly. "lat_sig catch" microbenchmark numbers (for x86, x86_64, x86_32 binaries) are with in the noise range with this change. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1343171129-2747-4-git-send-email-suresh.b.siddha@intel.com [ Merged in compilation fix ] Link: http://lkml.kernel.org/r/1344544736.8326.17.camel@sbsiddha-desk.sc.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-06-01x86, x32, ptrace: Remove PTRACE_ARCH_PRCTL for x32H.J. Lu
When I added x32 ptrace to 3.4 kernel, I also include PTRACE_ARCH_PRCTL support for x32 GDB For ARCH_GET_FS/GS, it takes a pointer to int64. But at user level, ARCH_GET_FS/GS takes a pointer to int32. So I have to add x32 ptrace to glibc to handle it with a temporary int64 passed to kernel and copy it back to GDB as int32. Roland suggested that PTRACE_ARCH_PRCTL is obsolete and x32 GDB should use fs_base and gs_base fields of user_regs_struct instead. Accordingly, remove PTRACE_ARCH_PRCTL completely from the x32 code to avoid possible memory overrun when pointer to int32 is passed to kernel. Link: http://lkml.kernel.org/r/CAMe9rOpDzHfS7NH7m1vmD9QRw8SSj4Sc%2BaNOgcWm_WJME2eRsQ@mail.gmail.com Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: <stable@vger.kernel.org> v3.4