kprobes, ftrace: Allow probing on some functions

There is no need to prohibit probing on the functions
used for preparation and uprobe only fetch functions.
Those are safely probed because those are not invoked
from kprobe's breakpoint/fault/debug handlers. So there
is no chance to cause recursive exceptions.

Following functions are now removed from the kprobes blacklist:

	update_bitfield_fetch_param
	free_bitfield_fetch_param
	kprobe_register
	FETCH_FUNC_NAME(stack, type) in trace_uprobe.c
	FETCH_FUNC_NAME(memory, type) in trace_uprobe.c
	FETCH_FUNC_NAME(memory, string) in trace_uprobe.c
	FETCH_FUNC_NAME(memory, string_size) in trace_uprobe.c
	FETCH_FUNC_NAME(file_offset, type) in trace_uprobe.c

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20140417081800.26341.56504.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 903ae28962be7f513c2a382631da4da2aeef377e..aa5f0bfcdf7b13a3107ebbdcd23e60e1ef177c6d 100644 (file)
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1196,9 +1196,8 @@ kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
  * kprobe_trace_self_tests_init() does enable_trace_probe/disable_trace_probe
  * lockless, but we can't race with this __init function.
  */
-static __kprobes
-int kprobe_register(struct ftrace_event_call *event,
-                   enum trace_reg type, void *data)
+static int kprobe_register(struct ftrace_event_call *event,
+                          enum trace_reg type, void *data)
 {
        struct trace_kprobe *tk = (struct trace_kprobe *)event->data;
        struct ftrace_event_file *file = data;

diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 8364a421b4dfc7bb8935cf4e9c128aa99de0776f..d3a91e40a6595e6b10ca908c4d14007d0eafa158 100644 (file)
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -183,7 +183,7 @@ DEFINE_BASIC_FETCH_FUNCS(bitfield)
 #define fetch_bitfield_string          NULL
 #define fetch_bitfield_string_size     NULL
 
-static __kprobes void
+static void
 update_bitfield_fetch_param(struct bitfield_fetch_param *data)
 {
        /*
@@ -196,7 +196,7 @@ update_bitfield_fetch_param(struct bitfield_fetch_param *data)
                update_symbol_cache(data->orig.data);
 }
 
-static __kprobes void
+static void
 free_bitfield_fetch_param(struct bitfield_fetch_param *data)
 {
        /*

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index c082a74413455da972d2c9c115001b58fe55e5a7..991e3b7c4edb3d8f235fc524cd100c47f53c8d92 100644 (file)
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -108,8 +108,8 @@ static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n)
  * Uprobes-specific fetch functions
  */
 #define DEFINE_FETCH_stack(type)                                       \
-static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\
-                                         void *offset, void *dest)     \
+static void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,         \
+                                        void *offset, void *dest)      \
 {                                                                      \
        *(type *)dest = (type)get_user_stack_nth(regs,                  \
                                              ((unsigned long)offset)); \
@@ -120,8 +120,8 @@ DEFINE_BASIC_FETCH_FUNCS(stack)
 #define fetch_stack_string_size        NULL
 
 #define DEFINE_FETCH_memory(type)                                      \
-static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\
-                                               void *addr, void *dest) \
+static void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,                \
+                                         void *addr, void *dest)       \
 {                                                                      \
        type retval;                                                    \
        void __user *vaddr = (void __force __user *) addr;              \
@@ -136,8 +136,8 @@ DEFINE_BASIC_FETCH_FUNCS(memory)
  * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
  * length and relative data location.
  */
-static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
-                                                     void *addr, void *dest)
+static void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
+                                           void *addr, void *dest)
 {
        long ret;
        u32 rloc = *(u32 *)dest;
@@ -158,8 +158,8 @@ static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
        }
 }
 
-static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
-                                                     void *addr, void *dest)
+static void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
+                                                void *addr, void *dest)
 {
        int len;
        void __user *vaddr = (void __force __user *) addr;
@@ -184,8 +184,8 @@ static unsigned long translate_user_vaddr(void *file_offset)
 }
 
 #define DEFINE_FETCH_file_offset(type)                                 \
-static __kprobes void FETCH_FUNC_NAME(file_offset, type)(struct pt_regs *regs,\
-                                       void *offset, void *dest)       \
+static void FETCH_FUNC_NAME(file_offset, type)(struct pt_regs *regs,   \
+                                              void *offset, void *dest)\
 {                                                                      \
        void *vaddr = (void *)translate_user_vaddr(offset);             \
                                                                        \