[FIX] uprobe: memory access to US for x86 81/48681/2
authorVyacheslav Cherkashin <v.cherkashin@samsung.com>
Thu, 24 Sep 2015 15:33:49 +0000 (18:33 +0300)
committerDmitry Kovalenko <d.kovalenko@samsung.com>
Thu, 24 Sep 2015 15:36:24 +0000 (08:36 -0700)
Change-Id: Ib24db9b392855a82ace15dfe282119c1047e4470
Signed-off-by: Vyacheslav Cherkashin <v.cherkashin@samsung.com>
uprobe/arch/x86/swap-asm/swap_uprobes.c

index c743cde..518c304 100644 (file)
@@ -189,21 +189,22 @@ int arch_prepare_uretprobe(struct uretprobe_instance *ri, struct pt_regs *regs)
 {
        /* Replace the return addr with trampoline addr */
        unsigned long ra = trampoline_addr(&ri->rp->up);
+       unsigned long ret_addr;
        ri->sp = (kprobe_opcode_t *)regs->sp;
 
-       if (!read_proc_vm_atomic(current, regs->EREG(sp), &(ri->ret_addr),
-                                sizeof(ri->ret_addr))) {
-               printk(KERN_ERR "failed to read user space func ra %lx addr=%p!\n",
-                               regs->EREG(sp), ri->rp->up.kp.addr);
+       if (get_user(ret_addr, (unsigned long *)regs->sp)) {
+               pr_err("failed to read user space func ra %lx addr=%p!\n",
+                      regs->sp, ri->rp->up.kp.addr);
                return -EINVAL;
        }
 
-       if (!write_proc_vm_atomic(current, regs->EREG(sp), &ra, sizeof(ra))) {
-               printk(KERN_ERR "failed to write user space func ra %lx!\n",
-                      regs->EREG(sp));
+       if (put_user(ra, (unsigned long *)regs->sp)) {
+               pr_err("failed to write user space func ra %lx!\n", regs->sp);
                return -EINVAL;
        }
 
+       ri->ret_addr = (kprobe_opcode_t *)ret_addr;
+
        return 0;
 }
 
@@ -218,7 +219,6 @@ int arch_prepare_uretprobe(struct uretprobe_instance *ri, struct pt_regs *regs)
 int arch_disarm_urp_inst(struct uretprobe_instance *ri,
                         struct task_struct *task, unsigned long tr)
 {
-       int len;
        unsigned long ret_addr;
        unsigned long sp = (unsigned long)ri->sp;
        unsigned long tramp_addr;
@@ -228,17 +228,14 @@ int arch_disarm_urp_inst(struct uretprobe_instance *ri,
        else
                tramp_addr = tr; /* ri - invalid */
 
-       len = read_proc_vm_atomic(task, sp, &ret_addr, sizeof(ret_addr));
-       if (len != sizeof(ret_addr)) {
+       if (get_user(ret_addr, (unsigned long *)sp)) {
                printk(KERN_INFO "---> %s (%d/%d): failed to read stack from %08lx\n",
                       task->comm, task->tgid, task->pid, sp);
                return -EFAULT;
        }
 
        if (tramp_addr == ret_addr) {
-               len = write_proc_vm_atomic(task, sp, &ri->ret_addr,
-                                          sizeof(ri->ret_addr));
-               if (len != sizeof(ri->ret_addr)) {
+               if (put_user((unsigned long)ri->ret_addr, (unsigned long *)sp)) {
                        printk(KERN_INFO "---> %s (%d/%d): failed to write "
                               "orig_ret_addr to %08lx",
                               task->comm, task->tgid, task->pid, sp);
@@ -329,10 +326,9 @@ static void set_user_jmp_op(void *from, void *to)
        jop.raddr = (long)(to) - ((long)(from) + 5);
        jop.op = RELATIVEJUMP_INSTRUCTION;
 
-       if (!write_proc_vm_atomic(current, (unsigned long)from, &jop,
-                                 sizeof(jop)))
-               printk(KERN_WARNING
-                      "failed to write jump opcode to user space %p\n", from);
+       if (put_user(jop.op, (char *)from) ||
+           put_user(jop.raddr, (long *)(from + 1)))
+               pr_err("failed to write jump opcode to user space %p\n", from);
 }
 
 static void resume_execution(struct kprobe *p,
@@ -347,19 +343,13 @@ static void resume_execution(struct kprobe *p,
        regs->EREG(flags) &= ~TF_MASK;
 
        tos = (unsigned long *)&tos_dword;
-       if (!read_proc_vm_atomic(current, regs->EREG(sp), &tos_dword,
-                                sizeof(tos_dword))) {
-               printk(KERN_WARNING
-                      "failed to read dword from top of the user space stack %lx!\n",
-                      regs->sp);
+       if (get_user(tos_dword, (unsigned long *)regs->sp)) {
+               pr_err("failed to read from user space sp=%lx!\n", regs->sp);
                return;
        }
 
-       if (!read_proc_vm_atomic(current, (unsigned long)p->ainsn.insn, insns,
-                                2 * sizeof(kprobe_opcode_t))) {
-               printk(KERN_WARNING
-                      "failed to read first 2 opcodes of instruction copy from user space %p!\n",
-                      p->ainsn.insn);
+       if (get_user(*(unsigned short *)insns, (unsigned short *)p->ainsn.insn)) {
+               pr_err("failed to read first 2 opcodes %p!\n", p->ainsn.insn);
                return;
        }
 
@@ -383,13 +373,8 @@ static void resume_execution(struct kprobe *p,
        case 0x9a: /* call absolute -- same as call absolute, indirect */
                *tos = orig_eip + (*tos - copy_eip);
 
-               if (!write_proc_vm_atomic(current,
-                                         regs->EREG(sp),
-                                         &tos_dword,
-                                         sizeof(tos_dword))) {
-                       printk(KERN_WARNING
-                              "failed to write dword to top of the user space stack %lx!\n",
-                              regs->sp);
+               if (put_user(tos_dword, (unsigned long *)regs->sp)) {
+                       pr_err("failed to write dword to sp=%lx\n", regs->sp);
                        return;
                }
 
@@ -403,12 +388,8 @@ static void resume_execution(struct kprobe *p,
                         */
                        *tos = orig_eip + (*tos - copy_eip);
 
-                       if (!write_proc_vm_atomic(current, regs->EREG(sp),
-                                                 &tos_dword,
-                                                 sizeof(tos_dword))) {
-                               printk(KERN_WARNING
-                                      "failed to write dword to top of the user space stack %lx!\n",
-                                      regs->EREG(sp));
+                       if (put_user(tos_dword, (unsigned long *)regs->sp)) {
+                               pr_err("failed to write dword to sp=%lx\n", regs->sp);
                                return;
                        }
 
@@ -430,11 +411,8 @@ static void resume_execution(struct kprobe *p,
                break;
        }
 
-       if (!write_proc_vm_atomic(current, regs->EREG(sp), &tos_dword,
-                                 sizeof(tos_dword))) {
-               printk(KERN_WARNING
-                      "failed to write dword to top of the user space stack %lx!\n",
-                      regs->EREG(sp));
+       if (put_user(tos_dword, (unsigned long *)regs->sp)) {
+               pr_err("failed to write dword to sp=%lx\n", regs->sp);
                return;
        }