From 69f447cffb911bb2d9737fa905f6d983ec2aa5d3 Mon Sep 17 00:00:00 2001 From: Roman Zippel Date: Sat, 3 Sep 2005 15:57:08 -0700 Subject: [PATCH] m68k: sys_ptrace cleanup - create helper function singlestep_disable() - move variable definitions to the top of the function - use "out_eio" label as common error destination - don't clear failure value for PTRACE_SETREGS/PTRACE_GETREGS Signed-off-by: Roman Zippel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/m68k/kernel/ptrace.c | 175 +++++++++++++++++----------------------------- 1 file changed, 64 insertions(+), 111 deletions(-) (limited to 'arch/m68k') diff --git a/arch/m68k/kernel/ptrace.c b/arch/m68k/kernel/ptrace.c index 9bb25ea78677..8ed1b01a6a87 100644 --- a/arch/m68k/kernel/ptrace.c +++ b/arch/m68k/kernel/ptrace.c @@ -103,48 +103,56 @@ static inline int put_reg(struct task_struct *task, int regno, } /* - * Called by kernel/ptrace.c when detaching.. - * * Make sure the single step bit is not set. */ -void ptrace_disable(struct task_struct *child) +static inline void singlestep_disable(struct task_struct *child) { - unsigned long tmp; - /* make sure the single step bit is not set. */ - tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16); + unsigned long tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16); put_reg(child, PT_SR, tmp); child->thread.work.delayed_trace = 0; +} + +/* + * Called by kernel/ptrace.c when detaching.. + */ +void ptrace_disable(struct task_struct *child) +{ + singlestep_disable(child); child->thread.work.syscall_trace = 0; } asmlinkage int sys_ptrace(long request, long pid, long addr, long data) { struct task_struct *child; - int ret; + unsigned long tmp; + int i, ret = 0; lock_kernel(); - ret = -EPERM; if (request == PTRACE_TRACEME) { /* are we already being traced? */ - if (current->ptrace & PT_PTRACED) + if (current->ptrace & PT_PTRACED) { + ret = -EPERM; goto out; + } /* set the ptrace bit in the process flags. */ current->ptrace |= PT_PTRACED; - ret = 0; goto out; } - ret = -ESRCH; read_lock(&tasklist_lock); child = find_task_by_pid(pid); if (child) get_task_struct(child); read_unlock(&tasklist_lock); - if (!child) + if (unlikely(!child)) { + ret = -ESRCH; goto out; + } - ret = -EPERM; - if (pid == 1) /* you may not mess with init */ + /* you may not mess with init */ + if (unlikely(pid == 1)) { + ret = -EPERM; goto out_tsk; + } if (request == PTRACE_ATTACH) { ret = ptrace_attach(child); @@ -152,86 +160,62 @@ asmlinkage int sys_ptrace(long request, long pid, long addr, long data) } ret = ptrace_check_attach(child, request == PTRACE_KILL); - if (ret < 0) + if (ret) goto out_tsk; switch (request) { /* when I and D space are separate, these will need to be fixed. */ case PTRACE_PEEKTEXT: /* read word at location addr. */ - case PTRACE_PEEKDATA: { - unsigned long tmp; - int copied; - - copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); - ret = -EIO; - if (copied != sizeof(tmp)) - break; + case PTRACE_PEEKDATA: + i = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); + if (i != sizeof(tmp)) + goto out_eio; ret = put_user(tmp, (unsigned long *)data); break; - } /* read the word at location addr in the USER area. */ - case PTRACE_PEEKUSR: { - unsigned long tmp; - - ret = -EIO; - if ((addr & 3) || addr < 0 || - addr > sizeof(struct user) - 3) - break; + case PTRACE_PEEKUSR: + if (addr & 3) + goto out_eio; + addr >>= 2; /* temporary hack. */ - tmp = 0; /* Default return condition */ - addr = addr >> 2; /* temporary hack. */ - ret = -EIO; - if (addr < 19) { + if (addr >= 0 && addr < 19) { tmp = get_reg(child, addr); if (addr == PT_SR) tmp >>= 16; } else if (addr >= 21 && addr < 49) { tmp = child->thread.fp[addr - 21]; -#ifdef CONFIG_M68KFPU_EMU /* Convert internal fpu reg representation * into long double format */ if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) tmp = ((tmp & 0xffff0000) << 15) | ((tmp & 0x0000ffff) << 16); -#endif } else break; ret = put_user(tmp, (unsigned long *)data); break; - } /* when I and D space are separate, this will have to be fixed. */ case PTRACE_POKETEXT: /* write the word at location addr. */ case PTRACE_POKEDATA: - ret = 0; - if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data)) - break; - ret = -EIO; + if (access_process_vm(child, addr, &data, sizeof(data), 1) != sizeof(data)) + goto out_eio; break; case PTRACE_POKEUSR: /* write the word at location addr in the USER area */ - ret = -EIO; - if ((addr & 3) || addr < 0 || - addr > sizeof(struct user) - 3) - break; - - addr = addr >> 2; /* temporary hack. */ + if (addr & 3) + goto out_eio; + addr >>= 2; /* temporary hack. */ if (addr == PT_SR) { data &= SR_MASK; data <<= 16; data |= get_reg(child, PT_SR) & ~(SR_MASK << 16); - } - if (addr < 19) { + } else if (addr >= 0 && addr < 19) { if (put_reg(child, addr, data)) - break; - ret = 0; - break; - } - if (addr >= 21 && addr < 48) { -#ifdef CONFIG_M68KFPU_EMU + goto out_eio; + } else if (addr >= 21 && addr < 48) { /* Convert long double format * into internal fpu reg representation */ @@ -240,60 +224,42 @@ asmlinkage int sys_ptrace(long request, long pid, long addr, long data) data = (data & 0xffff0000) | ((data & 0x0000ffff) >> 1); } -#endif child->thread.fp[addr - 21] = data; - ret = 0; - } + } else + goto out_eio; break; case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ - case PTRACE_CONT: { /* restart after signal. */ - long tmp; - - ret = -EIO; + case PTRACE_CONT: /* restart after signal. */ if (!valid_signal(data)) - break; - if (request == PTRACE_SYSCALL) { + goto out_eio; + + if (request == PTRACE_SYSCALL) child->thread.work.syscall_trace = ~0; - } else { + else child->thread.work.syscall_trace = 0; - } child->exit_code = data; - /* make sure the single step bit is not set. */ - tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16); - put_reg(child, PT_SR, tmp); - child->thread.work.delayed_trace = 0; + singlestep_disable(child); wake_up_process(child); - ret = 0; break; - } /* * make the child exit. Best I can do is send it a sigkill. * perhaps it should be put in the status that it wants to * exit. */ - case PTRACE_KILL: { - long tmp; - - ret = 0; + case PTRACE_KILL: if (child->exit_state == EXIT_ZOMBIE) /* already dead */ break; child->exit_code = SIGKILL; - /* make sure the single step bit is not set. */ - tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16); - put_reg(child, PT_SR, tmp); - child->thread.work.delayed_trace = 0; + singlestep_disable(child); wake_up_process(child); break; - } - - case PTRACE_SINGLESTEP: { /* set the trap flag. */ - long tmp; - ret = -EIO; + case PTRACE_SINGLESTEP: /* set the trap flag. */ if (!valid_signal(data)) - break; + goto out_eio; + child->thread.work.syscall_trace = 0; tmp = get_reg(child, PT_SR) | (TRACE_BITS << 16); put_reg(child, PT_SR, tmp); @@ -302,39 +268,29 @@ asmlinkage int sys_ptrace(long request, long pid, long addr, long data) child->exit_code = data; /* give it a chance to run. */ wake_up_process(child); - ret = 0; break; - } case PTRACE_DETACH: /* detach a process that was attached. */ ret = ptrace_detach(child, data); break; - case PTRACE_GETREGS: { /* Get all gp regs from the child. */ - int i; - unsigned long tmp; + case PTRACE_GETREGS: /* Get all gp regs from the child. */ for (i = 0; i < 19; i++) { tmp = get_reg(child, i); if (i == PT_SR) tmp >>= 16; - if (put_user(tmp, (unsigned long *)data)) { - ret = -EFAULT; + ret = put_user(tmp, (unsigned long *)data); + if (ret) break; - } data += sizeof(long); } - ret = 0; break; - } - case PTRACE_SETREGS: { /* Set all gp regs in the child. */ - int i; - unsigned long tmp; + case PTRACE_SETREGS: /* Set all gp regs in the child. */ for (i = 0; i < 19; i++) { - if (get_user(tmp, (unsigned long *)data)) { - ret = -EFAULT; + ret = get_user(tmp, (unsigned long *)data); + if (ret) break; - } if (i == PT_SR) { tmp &= SR_MASK; tmp <<= 16; @@ -343,25 +299,19 @@ asmlinkage int sys_ptrace(long request, long pid, long addr, long data) put_reg(child, i, tmp); data += sizeof(long); } - ret = 0; break; - } - case PTRACE_GETFPREGS: { /* Get the child FPU state. */ - ret = 0; + case PTRACE_GETFPREGS: /* Get the child FPU state. */ if (copy_to_user((void *)data, &child->thread.fp, sizeof(struct user_m68kfp_struct))) ret = -EFAULT; break; - } - case PTRACE_SETFPREGS: { /* Set the child FPU state. */ - ret = 0; + case PTRACE_SETFPREGS: /* Set the child FPU state. */ if (copy_from_user(&child->thread.fp, (void *)data, sizeof(struct user_m68kfp_struct))) ret = -EFAULT; break; - } default: ret = ptrace_request(child, request, addr, data); @@ -372,6 +322,9 @@ out_tsk: out: unlock_kernel(); return ret; +out_eio: + ret = -EIO; + goto out_tsk; } asmlinkage void syscall_trace(void) -- cgit v1.2.3