From: Andy Lutomirski <luto@kernel.org>
To: x86@kernel.org
Cc: linux-kernel@vger.kernel.org, Brian Gerst <brgerst@gmail.com>,
Borislav Petkov <bp@alien8.de>, Andy Lutomirski <luto@kernel.org>
Subject: [PATCH 08/11] x86: Move uaccess_err and sig_on_uaccess_err to thread_struct
Date: Thu, 14 Jul 2016 13:22:56 -0700 [thread overview]
Message-ID: <d0ac4d01c8e4d4d756264604e47445d5acc7900e.1468527351.git.luto@kernel.org> (raw)
In-Reply-To: <cover.1468527351.git.luto@kernel.org>
In-Reply-To: <cover.1468527351.git.luto@kernel.org>
thread_info is a legacy mess. To prepare for its partial removal,
move the uaccess control fields out -- they're straightforward.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
---
arch/x86/entry/vsyscall/vsyscall_64.c | 6 +++---
arch/x86/include/asm/processor.h | 3 +++
arch/x86/include/asm/thread_info.h | 2 --
arch/x86/include/asm/uaccess.h | 4 ++--
arch/x86/mm/extable.c | 2 +-
arch/x86/mm/fault.c | 2 +-
6 files changed, 10 insertions(+), 9 deletions(-)
diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c
index 174c2549939d..3aba2b043050 100644
--- a/arch/x86/entry/vsyscall/vsyscall_64.c
+++ b/arch/x86/entry/vsyscall/vsyscall_64.c
@@ -221,8 +221,8 @@ bool emulate_vsyscall(struct pt_regs *regs, unsigned long address)
* With a real vsyscall, page faults cause SIGSEGV. We want to
* preserve that behavior to make writing exploits harder.
*/
- prev_sig_on_uaccess_error = current_thread_info()->sig_on_uaccess_error;
- current_thread_info()->sig_on_uaccess_error = 1;
+ prev_sig_on_uaccess_error = current->thread.sig_on_uaccess_error;
+ current->thread.sig_on_uaccess_error = 1;
ret = -EFAULT;
switch (vsyscall_nr) {
@@ -243,7 +243,7 @@ bool emulate_vsyscall(struct pt_regs *regs, unsigned long address)
break;
}
- current_thread_info()->sig_on_uaccess_error = prev_sig_on_uaccess_error;
+ current->thread.sig_on_uaccess_error = prev_sig_on_uaccess_error;
check_fault:
if (ret == -EFAULT) {
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 62c6cc3cc5d3..f53ae57bd985 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -419,6 +419,9 @@ struct thread_struct {
/* Max allowed port in the bitmap, in bytes: */
unsigned io_bitmap_max;
+ unsigned int sig_on_uaccess_error:1;
+ unsigned int uaccess_err:1; /* uaccess failed */
+
/* Floating point and extended processor state */
struct fpu fpu;
/*
diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index 30c133ac05cd..7c47bb659ecd 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -58,8 +58,6 @@ struct thread_info {
__u32 status; /* thread synchronous flags */
__u32 cpu; /* current CPU */
mm_segment_t addr_limit;
- unsigned int sig_on_uaccess_error:1;
- unsigned int uaccess_err:1; /* uaccess failed */
};
#define INIT_THREAD_INFO(tsk) \
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index 2982387ba817..4d2a726e8e6d 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -468,13 +468,13 @@ struct __large_struct { unsigned long buf[100]; };
* uaccess_try and catch
*/
#define uaccess_try do { \
- current_thread_info()->uaccess_err = 0; \
+ current->thread.uaccess_err = 0; \
__uaccess_begin(); \
barrier();
#define uaccess_catch(err) \
__uaccess_end(); \
- (err) |= (current_thread_info()->uaccess_err ? -EFAULT : 0); \
+ (err) |= (current->thread.uaccess_err ? -EFAULT : 0); \
} while (0)
/**
diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c
index 4bb53b89f3c5..0f90cc218d04 100644
--- a/arch/x86/mm/extable.c
+++ b/arch/x86/mm/extable.c
@@ -37,7 +37,7 @@ bool ex_handler_ext(const struct exception_table_entry *fixup,
struct pt_regs *regs, int trapnr)
{
/* Special hack for uaccess_err */
- current_thread_info()->uaccess_err = 1;
+ current->thread.uaccess_err = 1;
regs->ip = ex_fixup_addr(fixup);
return true;
}
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index ca44e2e7fd00..69be03d4aca6 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -737,7 +737,7 @@ no_context(struct pt_regs *regs, unsigned long error_code,
* In this case we need to make sure we're not recursively
* faulting through the emulate_vsyscall() logic.
*/
- if (current_thread_info()->sig_on_uaccess_error && signal) {
+ if (current->thread.sig_on_uaccess_error && signal) {
tsk->thread.trap_nr = X86_TRAP_PF;
tsk->thread.error_code = error_code | PF_USER;
tsk->thread.cr2 = address;
--
2.7.4
next prev parent reply other threads:[~2016-07-14 20:23 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-14 20:22 [PATCH 00/11] x86: misc prep patches for virtually mapped stacks Andy Lutomirski
2016-07-14 20:22 ` [PATCH 01/11] x86/mm/hotplug: Don't remove PGD entries in remove_pagetable() Andy Lutomirski
2016-07-15 11:59 ` [tip:x86/mm] " tip-bot for Ingo Molnar
2016-07-14 20:22 ` [PATCH 02/11] x86/cpa: In populate_pgd, don't set the pgd entry until it's populated Andy Lutomirski
2016-07-15 11:59 ` [tip:x86/mm] x86/mm/cpa: In populate_pgd(), don't set the PGD " tip-bot for Andy Lutomirski
2016-07-14 20:22 ` [PATCH 03/11] x86/mm: Remove kernel_unmap_pages_in_pgd() and efi_cleanup_page_tables() Andy Lutomirski
2016-07-15 12:00 ` [tip:x86/mm] " tip-bot for Andy Lutomirski
2016-07-14 20:22 ` [PATCH 04/11] x86/dumpstack: Try harder to get a call trace on stack overflow Andy Lutomirski
2016-07-15 12:00 ` [tip:x86/mm] " tip-bot for Andy Lutomirski
2016-07-14 20:22 ` [PATCH 05/11] x86/dumpstack/64: Handle faults when printing the "Stack:" part of an OOPS Andy Lutomirski
2016-07-15 12:01 ` [tip:x86/mm] x86/dumpstack/64: Handle faults when printing the "Stack: " " tip-bot for Andy Lutomirski
2016-07-14 20:22 ` [PATCH 06/11] x86/mm/64: In vmalloc_fault(), use CR3 instead of current->active_mm Andy Lutomirski
2016-07-15 12:01 ` [tip:x86/mm] " tip-bot for Andy Lutomirski
2016-07-14 20:22 ` [PATCH 07/11] x86/dumpstack: When OOPSing, rewind the stack before do_exit() Andy Lutomirski
2016-07-15 12:02 ` [tip:x86/mm] " tip-bot for Andy Lutomirski
2016-07-14 20:22 ` Andy Lutomirski [this message]
2016-07-15 8:14 ` [PATCH 08/11] x86: Move uaccess_err and sig_on_uaccess_err to thread_struct Ingo Molnar
2016-07-15 12:02 ` [tip:x86/mm] x86/uaccess: Move thread_info::uaccess_err and thread_info::sig_on_uaccess_err " tip-bot for Andy Lutomirski
2016-07-14 20:22 ` [PATCH 09/11] x86: Move addr_limit " Andy Lutomirski
2016-07-15 12:03 ` [tip:x86/mm] x86/uaccess: Move thread_info::addr_limit " tip-bot for Andy Lutomirski
2016-07-14 20:22 ` [PATCH 10/11] x86/smp: Remove stack_smp_processor_id() Andy Lutomirski
2016-07-15 12:04 ` [tip:x86/mm] " tip-bot for Andy Lutomirski
2016-07-14 20:22 ` [PATCH 11/11] x86/smp: Remove unnecessary initialization of thread_info::cpu Andy Lutomirski
2016-07-15 12:04 ` [tip:x86/mm] " tip-bot for Andy Lutomirski
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