syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64 (f8781c4a) · Commits · e / devices / android_kernel_fairphone_FP5

arch/x86/Kconfig

+1 −5

Original line number	Original line	Diff line number	Diff line
	@@ -29,6 +29,7 @@ config X86_64
	select HAVE_ARCH_SOFT_DIRTY		select HAVE_ARCH_SOFT_DIRTY
	select MODULES_USE_ELF_RELA		select MODULES_USE_ELF_RELA
	select X86_DEV_DMA_OPS		select X86_DEV_DMA_OPS
			select ARCH_HAS_SYSCALL_WRAPPER

	#		#
	# Arch settings		# Arch settings
	@@ -2954,8 +2955,3 @@ source "crypto/Kconfig"
	source "arch/x86/kvm/Kconfig"		source "arch/x86/kvm/Kconfig"

	source "lib/Kconfig"		source "lib/Kconfig"

	config SYSCALL_PTREGS
	def_bool y
	depends on X86_64
	select ARCH_HAS_SYSCALL_WRAPPER

arch/x86/entry/common.c

+2 −8

Original line number	Original line	Diff line number	Diff line
	@@ -284,13 +284,7 @@ __visible void do_syscall_64(unsigned long nr, struct pt_regs *regs)
	nr &= __SYSCALL_MASK;		nr &= __SYSCALL_MASK;
	if (likely(nr < NR_syscalls)) {		if (likely(nr < NR_syscalls)) {
	nr = array_index_nospec(nr, NR_syscalls);		nr = array_index_nospec(nr, NR_syscalls);
	#ifdef CONFIG_SYSCALL_PTREGS
	regs->ax = sys_call_table[nr](regs);		regs->ax = sys_call_table[nr](regs);
	#else
	regs->ax = sys_call_table[nr](
	regs->di, regs->si, regs->dx,
	regs->r10, regs->r8, regs->r9);
	#endif
	}		}

	syscall_return_slowpath(regs);		syscall_return_slowpath(regs);
	@@ -325,7 +319,7 @@ static __always_inline void do_syscall_32_irqs_on(struct pt_regs *regs)

	if (likely(nr < IA32_NR_syscalls)) {		if (likely(nr < IA32_NR_syscalls)) {
	nr = array_index_nospec(nr, IA32_NR_syscalls);		nr = array_index_nospec(nr, IA32_NR_syscalls);
	#ifdef CONFIG_SYSCALL_PTREGS		#ifdef CONFIG_IA32_EMULATION
	regs->ax = ia32_sys_call_table[nr](regs);		regs->ax = ia32_sys_call_table[nr](regs);
	#else		#else
	/*		/*
	@@ -338,7 +332,7 @@ static __always_inline void do_syscall_32_irqs_on(struct pt_regs *regs)
	(unsigned int)regs->bx, (unsigned int)regs->cx,		(unsigned int)regs->bx, (unsigned int)regs->cx,
	(unsigned int)regs->dx, (unsigned int)regs->si,		(unsigned int)regs->dx, (unsigned int)regs->si,
	(unsigned int)regs->di, (unsigned int)regs->bp);		(unsigned int)regs->di, (unsigned int)regs->bp);
	#endif /* CONFIG_SYSCALL_PTREGS */		#endif /* CONFIG_IA32_EMULATION */
	}		}

	syscall_return_slowpath(regs);		syscall_return_slowpath(regs);

arch/x86/entry/syscall_32.c

+3 −3

Original line number	Original line	Diff line number	Diff line
	@@ -7,17 +7,17 @@
	#include <asm/asm-offsets.h>		#include <asm/asm-offsets.h>
	#include <asm/syscall.h>		#include <asm/syscall.h>

	#ifdef CONFIG_SYSCALL_PTREGS		#ifdef CONFIG_IA32_EMULATION
	/* On X86_64, we use struct pt_regs * to pass parameters to syscalls */		/* On X86_64, we use struct pt_regs * to pass parameters to syscalls */
	#define __SYSCALL_I386(nr, sym, qual) extern asmlinkage long sym(const struct pt_regs *);		#define __SYSCALL_I386(nr, sym, qual) extern asmlinkage long sym(const struct pt_regs *);

	/* this is a lie, but it does not hurt as sys_ni_syscall just returns -EINVAL */		/* this is a lie, but it does not hurt as sys_ni_syscall just returns -EINVAL */
	extern asmlinkage long sys_ni_syscall(const struct pt_regs *);		extern asmlinkage long sys_ni_syscall(const struct pt_regs *);

	#else /* CONFIG_SYSCALL_PTREGS */		#else /* CONFIG_IA32_EMULATION */
	#define __SYSCALL_I386(nr, sym, qual) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);		#define __SYSCALL_I386(nr, sym, qual) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
	extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);		extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
	#endif /* CONFIG_SYSCALL_PTREGS */		#endif /* CONFIG_IA32_EMULATION */

	#include <asm/syscalls_32.h>		#include <asm/syscalls_32.h>
	#undef __SYSCALL_I386		#undef __SYSCALL_I386

arch/x86/entry/syscall_64.c

+0 −5

Original line number	Original line	Diff line number	Diff line
	@@ -7,14 +7,9 @@
	#include <asm/asm-offsets.h>		#include <asm/asm-offsets.h>
	#include <asm/syscall.h>		#include <asm/syscall.h>

	#ifdef CONFIG_SYSCALL_PTREGS
	/* this is a lie, but it does not hurt as sys_ni_syscall just returns -EINVAL */		/* this is a lie, but it does not hurt as sys_ni_syscall just returns -EINVAL */
	extern asmlinkage long sys_ni_syscall(const struct pt_regs *);		extern asmlinkage long sys_ni_syscall(const struct pt_regs *);
	#define __SYSCALL_64(nr, sym, qual) extern asmlinkage long sym(const struct pt_regs *);		#define __SYSCALL_64(nr, sym, qual) extern asmlinkage long sym(const struct pt_regs *);
	#else /* CONFIG_SYSCALL_PTREGS */
	extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
	#define __SYSCALL_64(nr, sym, qual) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
	#endif /* CONFIG_SYSCALL_PTREGS */
	#include <asm/syscalls_64.h>		#include <asm/syscalls_64.h>
	#undef __SYSCALL_64		#undef __SYSCALL_64

arch/x86/entry/vsyscall/vsyscall_64.c

+0 −18

Original line number	Original line	Diff line number	Diff line
	@@ -127,9 +127,7 @@ bool emulate_vsyscall(struct pt_regs *regs, unsigned long address)
	int vsyscall_nr, syscall_nr, tmp;		int vsyscall_nr, syscall_nr, tmp;
	int prev_sig_on_uaccess_err;		int prev_sig_on_uaccess_err;
	long ret;		long ret;
	#ifdef CONFIG_SYSCALL_PTREGS
	unsigned long orig_dx;		unsigned long orig_dx;
	#endif

	/*		/*
	* No point in checking CS -- the only way to get here is a user mode		* No point in checking CS -- the only way to get here is a user mode
	@@ -230,38 +228,22 @@ bool emulate_vsyscall(struct pt_regs *regs, unsigned long address)
	ret = -EFAULT;		ret = -EFAULT;
	switch (vsyscall_nr) {		switch (vsyscall_nr) {
	case 0:		case 0:
	#ifdef CONFIG_SYSCALL_PTREGS
	/* this decodes regs->di and regs->si on its own */		/* this decodes regs->di and regs->si on its own */
	ret = sys_gettimeofday(regs);		ret = sys_gettimeofday(regs);
	#else
	ret = sys_gettimeofday(
	(struct timeval __user *)regs->di,
	(struct timezone __user *)regs->si);
	#endif /* CONFIG_SYSCALL_PTREGS */
	break;		break;

	case 1:		case 1:
	#ifdef CONFIG_SYSCALL_PTREGS
	/* this decodes regs->di on its own */		/* this decodes regs->di on its own */
	ret = sys_time(regs);		ret = sys_time(regs);
	#else
	ret = sys_time((time_t __user *)regs->di);
	#endif /* CONFIG_SYSCALL_PTREGS */
	break;		break;

	case 2:		case 2:
	#ifdef CONFIG_SYSCALL_PTREGS
	/* while we could clobber regs->dx, we didn't in the past... */		/* while we could clobber regs->dx, we didn't in the past... */
	orig_dx = regs->dx;		orig_dx = regs->dx;
	regs->dx = 0;		regs->dx = 0;
	/* this decodes regs->di, regs->si and regs->dx on its own */		/* this decodes regs->di, regs->si and regs->dx on its own */
	ret = sys_getcpu(regs);		ret = sys_getcpu(regs);
	regs->dx = orig_dx;		regs->dx = orig_dx;
	#else
	ret = sys_getcpu((unsigned __user *)regs->di,
	(unsigned __user *)regs->si,
	NULL);
	#endif /* CONFIG_SYSCALL_PTREGS */
	break;		break;
	}		}