Ingo Molnar
a5dd192496
Merge branch 'x86/urgent' into x86/asm to fix up conflicts and to pick up fixes
...
Conflicts:
arch/x86/entry/entry_64_compat.S
arch/x86/math-emu/get_address.c
Signed-off-by: Ingo Molnar <mingo@kernel.org >
2015-08-18 09:39:47 +02:00
Linus Torvalds
cd88ec2317
x86: fix error handling for 32-bit compat out-of-range system call numbers
...
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 >
2015-08-13 16:19:44 -07:00
Ingo Molnar
5b929bd11d
Merge branch 'x86/urgent' into x86/asm, before applying dependent patches
...
Signed-off-by: Ingo Molnar <mingo@kernel.org >
2015-07-31 10:23:35 +02:00
Denys Vlasenko
c0c3322e98
x86/asm/entry/32: Revert 'Do not use R9 in SYSCALL32' commit
...
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 >
2015-07-24 16:36:00 +02:00
Andy Lutomirski
8f7f06b87a
x86/entry/64: Fix IRQ state confusion and related warning on compat syscalls with CONFIG_AUDITSYSCALL=n
...
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 >
2015-07-08 21:10:25 +02:00
Andy Lutomirski
02bc7768fe
x86/asm/entry/64: Migrate error and IRQ exit work to C and remove 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/60e90901eee611e59e958bfdbbe39969b4f88fe5.1435952415.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org >
2015-07-07 10:59:08 +02:00
Andy Lutomirski
29ea1b258b
x86/entry/64: Migrate 64-bit and compat syscalls to the new exit handlers and remove old assembly code
...
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 >
2015-07-07 10:59:07 +02:00
Andy Lutomirski
5e99cb7c35
x86/entry/64/compat: Fix bad fast syscall arg failure path
...
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 >
2015-07-07 10:58:30 +02:00
Denys Vlasenko
c73e36b775
x86/asm/entry/32: Replace RESTORE_RSI_RDI with open-coded 32-bit reads
...
This doesn't change much, but uses shorter 32-bit insns:
-48 8b 74 24 68 mov 0x68(%rsp),%rsi
-48 8b 7c 24 70 mov 0x70(%rsp),%rdi
-48 8b 54 24 60 mov 0x60(%rsp),%rdx
+8b 54 24 60 mov 0x60(%rsp),%edx
+8b 74 24 68 mov 0x68(%rsp),%esi
+8b 7c 24 70 mov 0x70(%rsp),%edi
and does the loads in pt_regs order.
Since these are the only uses of RESTORE_RSI_RDI[_RDX], drop
these macros.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com >
Cc: Alexei Starovoitov <ast@plumgrid.com >
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/1435954742-2545-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org >
2015-07-06 14:56:50 +02:00
Denys Vlasenko
a92fde2523
x86/asm/entry/32: Shorten __audit_syscall_entry() args preparation
...
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 >
2015-06-10 08:42:13 +02:00
Denys Vlasenko
1536bb46fa
x86/asm/entry/32: Explain reloading of registers after __audit_syscall_entry()
...
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 >
2015-06-10 08:42:13 +02:00
Denys Vlasenko
aee4b013a7
x86/asm/entry/32: Fix fallout from the R9 trick removal in the SYSCALL code
...
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 >
2015-06-10 08:42:12 +02:00
Denys Vlasenko
9b47feb708
x86/asm/entry: Clean up entry*.S style, final bits
...
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 >
2015-06-09 11:48:24 +02:00
Denys Vlasenko
eb47854415
x86/asm/entry/32: Reinstate clearing of pt_regs->r8..r11 on EFAULT path
...
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 >
2015-06-08 23:43:37 +02:00
Ingo Molnar
4c8cd0c50d
x86/asm/entry: Untangle 'ia32_sysenter_target' into two entry points: entry_SYSENTER_32 and entry_SYSENTER_compat
...
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 >
2015-06-08 08:47:46 +02:00
Ingo Molnar
2cd23553b4
x86/asm/entry: Rename compat syscall entry points
...
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 >
2015-06-08 08:47:36 +02:00
Ingo Molnar
138bd56a21
x86/asm/entry/64/compat: Rename ia32entry.S -> entry_64_compat.S
...
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