Commit abfb9498 authored by Dmitry Safonov's avatar Dmitry Safonov Committed by Ingo Molnar
Browse files

x86/entry: Rename is_{ia32,x32}_task() to in_{ia32,x32}_syscall() 



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: default avatarAndy Lutomirski <luto@amacapital.net>
Suggested-by: default avatarIngo Molnar <mingo@kernel.org>
Signed-off-by: default avatarDmitry Safonov <dsafonov@virtuozzo.com>
[ Expanded the changelog. ]
Acked-by: default avatarAndy 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: default avatarIngo Molnar <mingo@kernel.org>
parent 6666ea55

arch/x86/entry/common.c

+1 −1
Original line number Diff line number Diff line
@@ -191,7 +191,7 @@ long syscall_trace_enter_phase2(struct pt_regs *regs, u32 arch, 


long syscall_trace_enter(struct pt_regs *regs)

{

	u32 arch = is_ia32_task() ? AUDIT_ARCH_I386 : AUDIT_ARCH_X86_64;

	u32 arch = in_ia32_syscall() ? AUDIT_ARCH_I386 : AUDIT_ARCH_X86_64;

	unsigned long phase1_result = syscall_trace_enter_phase1(regs, arch);



	if (phase1_result == 0)

arch/x86/include/asm/compat.h

+2 −2
Original line number Diff line number Diff line
@@ -307,7 +307,7 @@ static inline void __user *arch_compat_alloc_user_space(long len) 
	return (void __user *)round_down(sp - len, 16);

}



static inline bool is_x32_task(void)

static inline bool in_x32_syscall(void)

{

#ifdef CONFIG_X86_X32_ABI

	if (task_pt_regs(current)->orig_ax & __X32_SYSCALL_BIT)
@@ -318,7 +318,7 @@ static inline bool is_x32_task(void) 


static inline bool in_compat_syscall(void)

{

	return is_ia32_task() || is_x32_task();

	return in_ia32_syscall() || in_x32_syscall();

}

#define in_compat_syscall in_compat_syscall	/* override the generic impl */

arch/x86/include/asm/thread_info.h

+1 −1
Original line number Diff line number Diff line
@@ -255,7 +255,7 @@ static inline bool test_and_clear_restore_sigmask(void) 
	return true;

}



static inline bool is_ia32_task(void)

static inline bool in_ia32_syscall(void)

{

#ifdef CONFIG_X86_32

	return true;

arch/x86/kernel/process_64.c

+1 −1
Original line number Diff line number Diff line
@@ -210,7 +210,7 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long sp, 
	 */

	if (clone_flags & CLONE_SETTLS) {

#ifdef CONFIG_IA32_EMULATION

		if (is_ia32_task())

		if (in_ia32_syscall())

			err = do_set_thread_area(p, -1,

				(struct user_desc __user *)tls, 0);

		else

arch/x86/kernel/ptrace.c

+1 −1
Original line number Diff line number Diff line
@@ -1266,7 +1266,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request, 
			compat_ulong_t caddr, compat_ulong_t cdata)

{

#ifdef CONFIG_X86_X32_ABI

	if (!is_ia32_task())

	if (!in_ia32_syscall())

		return x32_arch_ptrace(child, request, caddr, cdata);

#endif

#ifdef CONFIG_IA32_EMULATION

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