Merge branch 'x86-vmware-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[pandora-kernel.git] / arch / x86 / kernel / kprobes.c

diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c
index 1bfb6cf..1cbd54c 100644 (file)
--- a/arch/x86/kernel/kprobes.c
+++ b/arch/x86/kernel/kprobes.c
@@ -230,9 +230,6 @@ static int recover_probed_instruction(kprobe_opcode_t *buf, unsigned long addr)
        return 0;
 }
 
-/* Dummy buffers for kallsyms_lookup */
-static char __dummy_buf[KSYM_NAME_LEN];
-
 /* Check if paddr is at an instruction boundary */
 static int __kprobes can_probe(unsigned long paddr)
 {
@@ -241,7 +238,7 @@ static int __kprobes can_probe(unsigned long paddr)
        struct insn insn;
        kprobe_opcode_t buf[MAX_INSN_SIZE];
 
-       if (!kallsyms_lookup(paddr, NULL, &offset, NULL, __dummy_buf))
+       if (!kallsyms_lookup_size_offset(paddr, NULL, &offset))
                return 0;
 
        /* Decode instructions */
@@ -709,6 +706,7 @@ static __used __kprobes void *trampoline_handler(struct pt_regs *regs)
        struct hlist_node *node, *tmp;
        unsigned long flags, orig_ret_address = 0;
        unsigned long trampoline_address = (unsigned long)&kretprobe_trampoline;
+       kprobe_opcode_t *correct_ret_addr = NULL;
 
        INIT_HLIST_HEAD(&empty_rp);
        kretprobe_hash_lock(current, &head, &flags);
@@ -740,14 +738,34 @@ static __used __kprobes void *trampoline_handler(struct pt_regs *regs)
                        /* another task is sharing our hash bucket */
                        continue;
 
+               orig_ret_address = (unsigned long)ri->ret_addr;
+
+               if (orig_ret_address != trampoline_address)
+                       /*
+                        * This is the real return address. Any other
+                        * instances associated with this task are for
+                        * other calls deeper on the call stack
+                        */
+                       break;
+       }
+
+       kretprobe_assert(ri, orig_ret_address, trampoline_address);
+
+       correct_ret_addr = ri->ret_addr;
+       hlist_for_each_entry_safe(ri, node, tmp, head, hlist) {
+               if (ri->task != current)
+                       /* another task is sharing our hash bucket */
+                       continue;
+
+               orig_ret_address = (unsigned long)ri->ret_addr;
                if (ri->rp && ri->rp->handler) {
                        __get_cpu_var(current_kprobe) = &ri->rp->kp;
                        get_kprobe_ctlblk()->kprobe_status = KPROBE_HIT_ACTIVE;
+                       ri->ret_addr = correct_ret_addr;
                        ri->rp->handler(ri, regs);
                        __get_cpu_var(current_kprobe) = NULL;
                }
 
-               orig_ret_address = (unsigned long)ri->ret_addr;
                recycle_rp_inst(ri, &empty_rp);
 
                if (orig_ret_address != trampoline_address)
@@ -759,8 +777,6 @@ static __used __kprobes void *trampoline_handler(struct pt_regs *regs)
                        break;
        }
 
-       kretprobe_assert(ri, orig_ret_address, trampoline_address);
-
        kretprobe_hash_unlock(current, &flags);
 
        hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) {
@@ -1110,7 +1126,7 @@ static void __kprobes synthesize_set_arg1(kprobe_opcode_t *addr,
        *(unsigned long *)addr = val;
 }
 
-void __kprobes kprobes_optinsn_template_holder(void)
+static void __used __kprobes kprobes_optinsn_template_holder(void)
 {
        asm volatile (
                        ".global optprobe_template_entry\n"
@@ -1202,7 +1218,8 @@ static int __kprobes copy_optimized_instructions(u8 *dest, u8 *src)
        }
        /* Check whether the address range is reserved */
        if (ftrace_text_reserved(src, src + len - 1) ||
-           alternatives_text_reserved(src, src + len - 1))
+           alternatives_text_reserved(src, src + len - 1) ||
+           jump_label_text_reserved(src, src + len - 1))
                return -EBUSY;
 
        return len;
@@ -1250,11 +1267,9 @@ static int __kprobes can_optimize(unsigned long paddr)
        unsigned long addr, size = 0, offset = 0;
        struct insn insn;
        kprobe_opcode_t buf[MAX_INSN_SIZE];
-       /* Dummy buffers for lookup_symbol_attrs */
-       static char __dummy_buf[KSYM_NAME_LEN];
 
        /* Lookup symbol including addr */
-       if (!kallsyms_lookup(paddr, &size, &offset, NULL, __dummy_buf))
+       if (!kallsyms_lookup_size_offset(paddr, &size, &offset))
                return 0;
 
        /* Check there is enough space for a relative jump. */