Merge branch 'perf/urgent' into perf/core, to pick up fixes

[karo-tx-linux.git] / kernel / kprobes.c

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 699c5bc51a9219d664578e4d7978dee94d291c82..d733479a10eeebc79250cf3905437a082b7300c9 100644 (file)
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1391,21 +1391,19 @@ bool within_kprobe_blacklist(unsigned long addr)
  * This returns encoded errors if it fails to look up symbol or invalid
  * combination of parameters.
  */
-static kprobe_opcode_t *kprobe_addr(struct kprobe *p)
+static kprobe_opcode_t *_kprobe_addr(kprobe_opcode_t *addr,
+                       const char *symbol_name, unsigned int offset)
 {
-       kprobe_opcode_t *addr = p->addr;
-
-       if ((p->symbol_name && p->addr) ||
-           (!p->symbol_name && !p->addr))
+       if ((symbol_name && addr) || (!symbol_name && !addr))
                goto invalid;
 
-       if (p->symbol_name) {
-               kprobe_lookup_name(p->symbol_name, addr);
+       if (symbol_name) {
+               kprobe_lookup_name(symbol_name, addr);
                if (!addr)
                        return ERR_PTR(-ENOENT);
        }
 
-       addr = (kprobe_opcode_t *)(((char *)addr) + p->offset);
+       addr = (kprobe_opcode_t *)(((char *)addr) + offset);
        if (addr)
                return addr;
 
@@ -1413,6 +1411,11 @@ invalid:
        return ERR_PTR(-EINVAL);
 }
 
+static kprobe_opcode_t *kprobe_addr(struct kprobe *p)
+{
+       return _kprobe_addr(p->addr, p->symbol_name, p->offset);
+}
+
 /* Check passed kprobe is valid and return kprobe in kprobe_table. */
 static struct kprobe *__get_valid_kprobe(struct kprobe *p)
 {
@@ -1740,11 +1743,12 @@ void unregister_kprobes(struct kprobe **kps, int num)
 }
 EXPORT_SYMBOL_GPL(unregister_kprobes);
 
-int __weak __kprobes kprobe_exceptions_notify(struct notifier_block *self,
-                                             unsigned long val, void *data)
+int __weak kprobe_exceptions_notify(struct notifier_block *self,
+                                       unsigned long val, void *data)
 {
        return NOTIFY_DONE;
 }
+NOKPROBE_SYMBOL(kprobe_exceptions_notify);
 
 static struct notifier_block kprobe_exceptions_nb = {
        .notifier_call = kprobe_exceptions_notify,
@@ -1875,6 +1879,25 @@ static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs)
 }
 NOKPROBE_SYMBOL(pre_handler_kretprobe);
 
+bool __weak arch_function_offset_within_entry(unsigned long offset)
+{
+       return !offset;
+}
+
+bool function_offset_within_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset)
+{
+       kprobe_opcode_t *kp_addr = _kprobe_addr(addr, sym, offset);
+
+       if (IS_ERR(kp_addr))
+               return false;
+
+       if (!kallsyms_lookup_size_offset((unsigned long)kp_addr, NULL, &offset) ||
+                                               !arch_function_offset_within_entry(offset))
+               return false;
+
+       return true;
+}
+
 int register_kretprobe(struct kretprobe *rp)
 {
        int ret = 0;
@@ -1882,6 +1905,9 @@ int register_kretprobe(struct kretprobe *rp)
        int i;
        void *addr;
 
+       if (!function_offset_within_entry(rp->kp.addr, rp->kp.symbol_name, rp->kp.offset))
+               return -EINVAL;
+
        if (kretprobe_blacklist_size) {
                addr = kprobe_addr(&rp->kp);
                if (IS_ERR(addr))