commit 6b8cf5cc9965673951f1ab3f0e3cf23d06e3e2ee upstream.
At entry userspace may have populated registers with values that could
otherwise be useful in a speculative execution attack. Clear them to
minimize the kernel's attack surface.
Originally-From: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>
Cc: 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: 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/151787989697.7847.4083702787288600552.stgit@dwillia2-desk3.amr.corp.intel.com
[ Made small improvements to the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com>
Reviewed-by: Alexey Makhalov <amakhalov@vmware.com>
Reviewed-by: Bo Gan <ganb@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 778843f934e362ed4ed734520f60a44a78a074b4 upstream
Use of a temporary R8 register here seems to be unnecessary.
"push %r8" is a two-byte insn (it needs REX prefix to specify R8),
"push $0" is two-byte too. It seems just using the latter would be
no worse.
Thus, code had an unnecessary "xorq %r8,%r8" insn.
It probably costs nothing in execution time here since we are probably
limited by store bandwidth at this point, but still.
Run-tested under QEMU: 32-bit calls still work:
/ # ./test_syscall_vdso32
[RUN] Executing 6-argument 32-bit syscall via VDSO
[OK] Arguments are preserved across syscall
[NOTE] R11 has changed:0000000000200ed7 - assuming clobbered by SYSRET insn
[OK] R8..R15 did not leak kernel data
[RUN] Executing 6-argument 32-bit syscall via INT 80
[OK] Arguments are preserved across syscall
[OK] R8..R15 did not leak kernel data
[RUN] Running tests under ptrace
[RUN] Executing 6-argument 32-bit syscall via VDSO
[OK] Arguments are preserved across syscall
[NOTE] R11 has changed:0000000000200ed7 - assuming clobbered by SYSRET insn
[OK] R8..R15 did not leak kernel data
[RUN] Executing 6-argument 32-bit syscall via INT 80
[OK] Arguments are preserved across syscall
[OK] R8..R15 did not leak kernel data
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-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: 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: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1462201010-16846-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com>
Reviewed-by: Alexey Makhalov <amakhalov@vmware.com>
Reviewed-by: Bo Gan <ganb@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merged performance improvements to Kaiser, using distinct kernel
and user Process Context Identifiers to minimize the TLB flushing.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch introduces our implementation of KAISER (Kernel Address Isolation to
have Side-channels Efficiently Removed), a kernel isolation technique to close
hardware side channels on kernel address information.
More information about the patch can be found on:
https://github.com/IAIK/KAISER
From: Richard Fellner <richard.fellner@student.tugraz.at>
From: Daniel Gruss <daniel.gruss@iaik.tugraz.at>
X-Subject: [RFC, PATCH] x86_64: KAISER - do not map kernel in user mode
Date: Thu, 4 May 2017 14:26:50 +0200
Link: http://marc.info/?l=linux-kernel&m=149390087310405&w=2
Kaiser-4.10-SHA1: c4b1831d44c6144d3762ccc72f0c4e71a0c713e5
To: <linux-kernel@vger.kernel.org>
To: <kernel-hardening@lists.openwall.com>
Cc: <clementine.maurice@iaik.tugraz.at>
Cc: <moritz.lipp@iaik.tugraz.at>
Cc: Michael Schwarz <michael.schwarz@iaik.tugraz.at>
Cc: Richard Fellner <richard.fellner@student.tugraz.at>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <kirill.shutemov@linux.intel.com>
Cc: <anders.fogh@gdata-adan.de>
After several recent works [1,2,3] KASLR on x86_64 was basically
considered dead by many researchers. We have been working on an
efficient but effective fix for this problem and found that not mapping
the kernel space when running in user mode is the solution to this
problem [4] (the corresponding paper [5] will be presented at ESSoS17).
With this RFC patch we allow anybody to configure their kernel with the
flag CONFIG_KAISER to add our defense mechanism.
If there are any questions we would love to answer them.
We also appreciate any comments!
Cheers,
Daniel (+ the KAISER team from Graz University of Technology)
[1] http://www.ieee-security.org/TC/SP2013/papers/4977a191.pdf
[2] https://www.blackhat.com/docs/us-16/materials/us-16-Fogh-Using-Undocumented-CPU-Behaviour-To-See-Into-Kernel-Mode-And-Break-KASLR-In-The-Process.pdf
[3] https://www.blackhat.com/docs/us-16/materials/us-16-Jang-Breaking-Kernel-Address-Space-Layout-Randomization-KASLR-With-Intel-TSX.pdf
[4] https://github.com/IAIK/KAISER
[5] https://gruss.cc/files/kaiser.pdf
[patch based also on
https://raw.githubusercontent.com/IAIK/KAISER/master/KAISER/0001-KAISER-Kernel-Address-Isolation.patch]
Signed-off-by: Richard Fellner <richard.fellner@student.tugraz.at>
Signed-off-by: Moritz Lipp <moritz.lipp@iaik.tugraz.at>
Signed-off-by: Daniel Gruss <daniel.gruss@iaik.tugraz.at>
Signed-off-by: Michael Schwarz <michael.schwarz@iaik.tugraz.at>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3d44d51bd339766f0178f0cf2e8d048b4a4872aa upstream.
This doesn't seem to fix a regression -- I don't think the CLAC was
ever there.
I double-checked in a debugger: entries through the int80 gate do
not automatically clear AC.
Stable maintainers: I can provide a backport to 4.3 and earlier if
needed. This needs to be backported all the way to 3.10.
Reported-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
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>
Fixes: 63bcff2a30 ("x86, smap: Add STAC and CLAC instructions to control user space access")
Link: http://lkml.kernel.org/r/b02b7e71ae54074be01fc171cbd4b72517055c0e.1456345086.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It turns out that some Android versions hardcode the SYSENTER
calling convention. This is buggy and will cause problems no
matter what the kernel does. Nonetheless, we should try to
support it.
Credit goes to Linus for pointing out a clean way to handle
the SYSENTER/SYSCALL clobber differences while preserving
straightforward DWARF annotations.
I believe that the original offending Android commit was:
https://android.googlesource.com/platform%2Fbionic/+/7dc3684d7a2587e43e6d2a8e0e3f39bf759bd535
Reported-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-and-tested-by: Borislav Petkov <bp@alien8.de>
Cc: <mark.gross@intel.com>
Cc: Su Tao <tao.su@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: <frank.wang@intel.com>
Cc: <borun.fu@intel.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Mingwei Shi <mingwei.shi@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
After 32-bit syscall rewrite, and specifically after commit:
5f310f739b ("x86/entry/32: Re-implement SYSENTER using the new C path")
... the stack frame that is passed to xen_sysexit is no longer a
"standard" one (i.e. it's not pt_regs).
Since we end up calling xen_iret from xen_sysexit we don't need
to fix up the stack and instead follow entry_SYSENTER_32's IRET
path directly to xen_iret.
We can do the same thing for compat mode even though stack does
not need to be fixed. This will allow us to drop usergs_sysret32
paravirt op (in the subsequent patch)
Suggested-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: david.vrabel@citrix.com
Cc: konrad.wilk@oracle.com
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1447970147-1733-2-git-send-email-boris.ostrovsky@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When I rewrote entry_INT80_32, I thought that int80 was an
interrupt gate. It's a trap gate. *facepalm*
Thanks to Brian Gerst for pointing out that it's better to
change the entry code than to change the gate type.
Suggested-by: Brian Gerst <brgerst@gmail.com>
Reported-and-tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
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>
Fixes: 150ac78d63 ("x86/entry/32: Switch INT80 to the new C syscall path")
Link: http://lkml.kernel.org/r/dc09d9b574a5c1dcca996847875c73f8341ce0ad.1445035014.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The code under the label can normally be inline, without the
jumping back and forth but the latter is an optimization.
Document that.
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-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/20151009170859.GA24266@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If CS, SS and IP are as expected and FLAGS is compatible with
SYSRETL, then return from fast compat syscalls (both SYSCALL and
SYSENTER) using SYSRETL.
Unlike native 64-bit opportunistic SYSRET, this is not invisible
to user code: RCX and R8-R15 end up in a different state than
shown saved in pt_regs. To compensate, we only do this when
returning to the vDSO fast syscall return path. This won't
interfere with syscall restart, as we won't use SYSRETL when
returning to the INT80 restart instruction.
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>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/aa15e49db33773eb10b73d73466b6d5466d7856a.1444091585.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
What, you didn't realize that SYSENTER and SYSCALL were actually
the same thing? :)
Unlike the old code, this actually passes the ptrace_syscall_32
test on AMD systems.
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>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/b74615af58d785aa02d917213ec64e2022a2c796.1444091585.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This is conceptually simpler. More importantly, it eliminates
the PTREGSCALL and execve stubs, which were not compatible with
the C ABI. This means that C code can call through the compat
syscall table.
The execve stubs are a bit subtle. They did two things: they
cleared some registers and they forced slow-path return.
Neither is necessary any more: elf_common_init clears the extra
registers and start_thread calls force_iret().
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>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/f95b7f7dfaacf88a8cae85bb06226cae53769287.1444091584.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We now have only one code path that calls through the compat
syscall table. This will make it much more pleasant to change
the pt_regs vs register calling convention, which we need to do
to move the call into C.
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>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/320cda5573cefdc601b955d23fbe8f36c085432d.1444091584.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
These audit optimizations are messy and hard to maintain. We'll
get a similar effect from opportunistic sysret when fast compat
system calls are re-implemented.
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>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/0bcca79ac7ff835d0e5a38725298865b01347a82.1444091584.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We've disabled the vDSO helpers to call them, so turn off the
entries entirely (temporarily) in preparation for cleaning them
up.
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>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/8d6e84bf651519289dc532dcc230adfabbd2a3eb.1444091584.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We eventually want to make it all the way into C code before
enabling interrupts. We need to rework our flags handling
slightly to delay enabling interrupts.
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>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/35d24d2a9305da3182eab7b2cdfd32902e90962c.1444091584.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Clearing NT is part of the prologue, whereas loading up arg6
makes more sense to think about as part of syscall processing.
Reorder them.
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>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/19eb235828b2d2a52c53459e09f2974e15e65a35.1444091584.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit 3f5159a922 ("x86/asm/entry/32: Update -ENOSYS handling to match
the 64-bit logic") broke the ENOSYS handling for the 32-bit compat case.
The proper error return value was never loaded into %rax, except if
things just happened to go through the audit paths, which ended up
reloading the return value.
This moves the loading or %rax into the normal system call path, just to
make sure the error case triggers it. It's kind of sad, since it adds a
useless instruction to reload the register to the fast path, but it's
not like that single load from the stack is going to be noticeable.
Reported-by: David Drysdale <drysdale@google.com>
Tested-by: Kees Cook <keescook@chromium.org>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This change reverts most of commit 53e9accf0f 'Do not use R9 in
SYSCALL32'. I don't yet understand how, but code in that commit
sometimes fails to preserve EBP.
See https://bugzilla.kernel.org/show_bug.cgi?id=101061
"Problems while executing 32-bit code on AMD64"
Reported-and-tested-by: Krzysztof A. Sobiecki <sobkas@gmail.com>
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Will Drewry <wad@chromium.org>
Cc: Kees Cook <keescook@chromium.org>
CC: x86@kernel.org
Link: http://lkml.kernel.org/r/1437740203-11552-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
int_ret_from_sys_call now expects IRQs to be enabled. I got
this right in the real sysexit_audit and sysretl_audit asm
paths, but I missed it in the #defined-away versions when
CONFIG_AUDITSYSCALL=n. This is a straightforward fix for
CONFIG_AUDITSYSCALL=n
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>
Fixes: 29ea1b258b ("x86/entry/64: Migrate 64-bit and compat syscalls to the new exit handlers and remove old assembly code")
Link: http://lkml.kernel.org/r/25cf0a01e01c6008118dd8f8d9f043020416700c.1436291493.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
These need to be migrated together, as the compat case used to
jump into the middle of the 64-bit exit code.
Remove the old assembly 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: 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/d4d1d70de08ac3640badf50048a9e8f18fe2497f.1435952415.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If user code does SYSCALL32 or SYSENTER without a valid stack,
then our attempt to determine the syscall args will result in a
failed uaccess fault. Previously, we would try to recover by
jumping to the syscall exit code, but we'd run the syscall exit
work even though we never made it to the syscall entry work.
Clean it up by treating the failure path as a non-syscall entry
and exit pair.
This fixes strace's output when running the syscall_arg_fault
test. Without this fix, strace would get out of sync and would
fail to associate syscall entries with syscall exits.
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/903010762c07a3d67df914fea2da84b52b0f8f1d.1435952415.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We use three MOVs to swap edx and ecx. We can use one XCHG
instead.
Expand the comments. It's difficult to keep track which arg#
every register corresponds to, so spell it out.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.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: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1433876051-26604-3-git-send-email-dvlasenk@redhat.com
[ Expanded the comments some more. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Here it is not obvious why we load pt_regs->cx to %esi etc.
Lets improve comments.
Explain that here we combine two things: first, we reload
registers since some of them are clobbered by the C function we
just called; and we also convert 32-bit syscall params to 64-bit
C ABI, because we are going to jump back to syscall dispatch
code.
Move reloading of 6th argument into the macro instead of having
it after each of two macro invocations.
No actual code changes here.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
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: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1433876051-26604-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
I put %ebp restoration code too late. Under strace, it is not
reached and %ebp is not restored upon return to userspace.
This is the fix. Run-tested.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
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: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1433876051-26604-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A few bits were missed.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
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>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
I broke this recently when I changed pt_regs->r8..r11 clearing
logic in INT 80 code path.
There is a branch from SYSENTER/SYSCALL code to INT 80 code:
if we fail to retrieve arg6, we return EFAULT. Before this
patch, in this case we don't clear pt_regs->r8..r11.
This patch fixes this. The resulting code is smaller and
simpler.
While at it, remove incorrect comment about syscall dispatching
CALL insn: it does not use RIP-relative addressing form (the
comment was meant to be "TODO: make this rip-relative", and
morphed since then, dropping "TODO").
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
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: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1433701470-28800-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
So the SYSENTER instruction is pretty quirky and it has different behavior
depending on bitness and CPU maker.
Yet we create a false sense of coherency by naming it 'ia32_sysenter_target'
in both of the cases.
Split the name into its two uses:
ia32_sysenter_target (32) -> entry_SYSENTER_32
ia32_sysenter_target (64) -> entry_SYSENTER_compat
As per the generic naming scheme for x86 system call entry points:
entry_MNEMONIC_qualifier
where 'qualifier' is one of _32, _64 or _compat.
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>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Rename the following system call entry points:
ia32_cstar_target -> entry_SYSCALL_compat
ia32_syscall -> entry_INT80_compat
The generic naming scheme for x86 system call entry points is:
entry_MNEMONIC_qualifier
where 'qualifier' is one of _32, _64 or _compat.
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>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
So we now have the following system entry code related
files, which define the following system call instruction
and other entry paths:
entry_32.S # 32-bit binaries on 32-bit kernels
entry_64.S # 64-bit binaries on 64-bit kernels
entry_64_compat.S # 32-bit binaries on 64-bit kernels
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.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: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Triplett <josh@joshtriplett.org>
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: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-07 14:56:50 +02:00
Renamed from arch/x86/entry/ia32entry.S (Browse further)
