linux-hardened/include/asm-arm/ptrace.h
Catalin Marinas d1cbbd6b41 [ARM] 4474/1: Do not check the PSR_F_BIT in valid_user_regs
When running Linux in non-secure mode (on ARM1176 for example),
depending on the CP15 secure configuration register, the CPSR.F bit
(6) might only be modified from the secure mode. However, the
valid_user_regs() function checks for this bit being cleared. With
commit a6c61e9d, a SIGSEGV is forced in handle_signal() if the user
registers are not considered valid.

The patch also ensures that the CPSR.A bit is cleared and the USR mode
is set if the CPU does not support the 26bit user mode.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-07-12 16:20:52 +01:00

164 lines
3.7 KiB
C

/*
* linux/include/asm-arm/ptrace.h
*
* Copyright (C) 1996-2003 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef __ASM_ARM_PTRACE_H
#define __ASM_ARM_PTRACE_H
#include <asm/hwcap.h>
#define PTRACE_GETREGS 12
#define PTRACE_SETREGS 13
#define PTRACE_GETFPREGS 14
#define PTRACE_SETFPREGS 15
/* PTRACE_ATTACH is 16 */
/* PTRACE_DETACH is 17 */
#define PTRACE_GETWMMXREGS 18
#define PTRACE_SETWMMXREGS 19
/* 20 is unused */
#define PTRACE_OLDSETOPTIONS 21
#define PTRACE_GET_THREAD_AREA 22
#define PTRACE_SET_SYSCALL 23
/* PTRACE_SYSCALL is 24 */
#define PTRACE_GETCRUNCHREGS 25
#define PTRACE_SETCRUNCHREGS 26
/*
* PSR bits
*/
#define USR26_MODE 0x00000000
#define FIQ26_MODE 0x00000001
#define IRQ26_MODE 0x00000002
#define SVC26_MODE 0x00000003
#define USR_MODE 0x00000010
#define FIQ_MODE 0x00000011
#define IRQ_MODE 0x00000012
#define SVC_MODE 0x00000013
#define ABT_MODE 0x00000017
#define UND_MODE 0x0000001b
#define SYSTEM_MODE 0x0000001f
#define MODE32_BIT 0x00000010
#define MODE_MASK 0x0000001f
#define PSR_T_BIT 0x00000020
#define PSR_F_BIT 0x00000040
#define PSR_I_BIT 0x00000080
#define PSR_A_BIT 0x00000100
#define PSR_J_BIT 0x01000000
#define PSR_Q_BIT 0x08000000
#define PSR_V_BIT 0x10000000
#define PSR_C_BIT 0x20000000
#define PSR_Z_BIT 0x40000000
#define PSR_N_BIT 0x80000000
#define PCMASK 0
/*
* Groups of PSR bits
*/
#define PSR_f 0xff000000 /* Flags */
#define PSR_s 0x00ff0000 /* Status */
#define PSR_x 0x0000ff00 /* Extension */
#define PSR_c 0x000000ff /* Control */
#ifndef __ASSEMBLY__
/*
* This struct defines the way the registers are stored on the
* stack during a system call. Note that sizeof(struct pt_regs)
* has to be a multiple of 8.
*/
struct pt_regs {
long uregs[18];
};
#define ARM_cpsr uregs[16]
#define ARM_pc uregs[15]
#define ARM_lr uregs[14]
#define ARM_sp uregs[13]
#define ARM_ip uregs[12]
#define ARM_fp uregs[11]
#define ARM_r10 uregs[10]
#define ARM_r9 uregs[9]
#define ARM_r8 uregs[8]
#define ARM_r7 uregs[7]
#define ARM_r6 uregs[6]
#define ARM_r5 uregs[5]
#define ARM_r4 uregs[4]
#define ARM_r3 uregs[3]
#define ARM_r2 uregs[2]
#define ARM_r1 uregs[1]
#define ARM_r0 uregs[0]
#define ARM_ORIG_r0 uregs[17]
#ifdef __KERNEL__
#define user_mode(regs) \
(((regs)->ARM_cpsr & 0xf) == 0)
#ifdef CONFIG_ARM_THUMB
#define thumb_mode(regs) \
(((regs)->ARM_cpsr & PSR_T_BIT))
#else
#define thumb_mode(regs) (0)
#endif
#define isa_mode(regs) \
((((regs)->ARM_cpsr & PSR_J_BIT) >> 23) | \
(((regs)->ARM_cpsr & PSR_T_BIT) >> 5))
#define processor_mode(regs) \
((regs)->ARM_cpsr & MODE_MASK)
#define interrupts_enabled(regs) \
(!((regs)->ARM_cpsr & PSR_I_BIT))
#define fast_interrupts_enabled(regs) \
(!((regs)->ARM_cpsr & PSR_F_BIT))
/* Are the current registers suitable for user mode?
* (used to maintain security in signal handlers)
*/
static inline int valid_user_regs(struct pt_regs *regs)
{
if (user_mode(regs) && (regs->ARM_cpsr & PSR_I_BIT) == 0) {
regs->ARM_cpsr &= ~(PSR_F_BIT | PSR_A_BIT);
return 1;
}
/*
* Force CPSR to something logical...
*/
regs->ARM_cpsr &= PSR_f | PSR_s | (PSR_x & ~PSR_A_BIT) | PSR_T_BIT | MODE32_BIT;
if (!(elf_hwcap & HWCAP_26BIT))
regs->ARM_cpsr |= USR_MODE;
return 0;
}
#endif /* __KERNEL__ */
#define pc_pointer(v) \
((v) & ~PCMASK)
#define instruction_pointer(regs) \
(pc_pointer((regs)->ARM_pc))
#ifdef CONFIG_SMP
extern unsigned long profile_pc(struct pt_regs *regs);
#else
#define profile_pc(regs) instruction_pointer(regs)
#endif
#ifdef __KERNEL__
#define predicate(x) ((x) & 0xf0000000)
#define PREDICATE_ALWAYS 0xe0000000
#endif
#endif /* __ASSEMBLY__ */
#endif