17 files changed, 64 insertions, 1 deletions

diff --git a/arch/avr32/kernel/kprobes.c b/arch/avr32/kernel/kprobes.c
index 4942ee662e0b..20b1c9d8f945 100644
--- a/arch/avr32/kernel/kprobes.c
+++ b/arch/avr32/kernel/kprobes.c
@@ -22,6 +22,8 @@ DEFINE_PER_CPU(struct kprobe *, current_kprobe);
 static unsigned long kprobe_status;
 static struct pt_regs jprobe_saved_regs;
 
+struct kretprobe_blackpoint kretprobe_blacklist[] = {{NULL, NULL}};
+
 int __kprobes arch_prepare_kprobe(struct kprobe *p)
 {
         int ret = 0;
diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c
index 5dc98b5abcfb..5fd65d8302c8 100644
--- a/arch/ia64/kernel/kprobes.c
+++ b/arch/ia64/kernel/kprobes.c
@@ -40,6 +40,8 @@ extern void jprobe_inst_return(void);
 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
 
+struct kretprobe_blackpoint kretprobe_blacklist[] = {{NULL, NULL}};
+
 enum instruction_type {A, I, M, F, B, L, X, u};
 static enum instruction_type bundle_encoding[32][3] = {
   { M, I, I },                          /* 00 */
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index 440f5a87271f..5338e4855712 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -38,6 +38,8 @@
 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
 
+struct kretprobe_blackpoint kretprobe_blacklist[] = {{NULL, NULL}};
+
 int __kprobes arch_prepare_kprobe(struct kprobe *p)
 {
         int ret = 0;
diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c
index e40373d9fbce..c5549a206284 100644
--- a/arch/s390/kernel/kprobes.c
+++ b/arch/s390/kernel/kprobes.c
@@ -33,6 +33,8 @@
 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
 
+struct kretprobe_blackpoint kretprobe_blacklist[] = {{NULL, NULL}};
+
 int __kprobes arch_prepare_kprobe(struct kprobe *p)
 {
         /* Make sure the probe isn't going on a difficult instruction */
diff --git a/arch/sparc64/kernel/kprobes.c b/arch/sparc64/kernel/kprobes.c
index c93a15b785fa..d94f901d321e 100644
--- a/arch/sparc64/kernel/kprobes.c
+++ b/arch/sparc64/kernel/kprobes.c
@@ -42,6 +42,8 @@
 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
 
+struct kretprobe_blackpoint kretprobe_blacklist[] = {{NULL, NULL}};
+
 int __kprobes arch_prepare_kprobe(struct kprobe *p)
 {
         p->ainsn.insn[0] = *p->addr;
diff --git a/arch/x86/kernel/kprobes_32.c b/arch/x86/kernel/kprobes_32.c
index 06b86e5617f6..90f778c04b3f 100644
--- a/arch/x86/kernel/kprobes_32.c
+++ b/arch/x86/kernel/kprobes_32.c
@@ -41,6 +41,13 @@ void jprobe_return_end(void);
 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
 
+struct kretprobe_blackpoint kretprobe_blacklist[] = {
+        {"__switch_to", }, /* This function switches only current task, but
+                             doesn't switch kernel stack.*/
+        {NULL, NULL}    /* Terminator */
+};
+const int kretprobe_blacklist_size = ARRAY_SIZE(kretprobe_blacklist);
+
 /* insert a jmp code */
 static __always_inline void set_jmp_op(void *from, void *to)
 {
diff --git a/arch/x86/kernel/kprobes_64.c b/arch/x86/kernel/kprobes_64.c
index 7c16506d681f..681b801c5e26 100644
--- a/arch/x86/kernel/kprobes_64.c
+++ b/arch/x86/kernel/kprobes_64.c
@@ -48,6 +48,13 @@ static void __kprobes arch_copy_kprobe(struct kprobe *p);
 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
 
+struct kretprobe_blackpoint kretprobe_blacklist[] = {
+        {"__switch_to", }, /* This function switches only current task, but
+                              doesn't switch kernel stack.*/
+        {NULL, NULL}    /* Terminator */
+};
+const int kretprobe_blacklist_size = ARRAY_SIZE(kretprobe_blacklist);
+
 /*
  * returns non-zero if opcode modifies the interrupt flag.
  */
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 7352d4b377e6..6309b275cb9c 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -581,7 +581,7 @@ static inline void __switch_to_xtra(struct task_struct *prev_p,
  *
  * Kprobes not supported here. Set the probe on schedule instead.
  */
-__kprobes struct task_struct *
+struct task_struct *
 __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 {
         struct thread_struct *prev = &prev_p->thread,
diff --git a/include/asm-avr32/kprobes.h b/include/asm-avr32/kprobes.h
index 0f3e636e6e4d..996cb656474e 100644
--- a/include/asm-avr32/kprobes.h
+++ b/include/asm-avr32/kprobes.h
@@ -17,6 +17,8 @@ typedef u16	kprobe_opcode_t;
 #define BREAKPOINT_INSTRUCTION  0xd673  /* breakpoint */
 #define MAX_INSN_SIZE           2
 
+#define kretprobe_blacklist_size 0
+
 #define arch_remove_kprobe(p)   do { } while (0)
 
 /* Architecture specific copy of original instruction */
diff --git a/include/asm-ia64/kprobes.h b/include/asm-ia64/kprobes.h
index 6c79edf24d73..a93ce9ef07ff 100644
--- a/include/asm-ia64/kprobes.h
+++ b/include/asm-ia64/kprobes.h
@@ -83,6 +83,7 @@ struct kprobe_ctlblk {
 };
 
 #define ARCH_SUPPORTS_KRETPROBES
+#define kretprobe_blacklist_size 0
 
 #define SLOT0_OPCODE_SHIFT      (37)
 #define SLOT1_p1_OPCODE_SHIFT   (37 - (64-46))
diff --git a/include/asm-powerpc/kprobes.h b/include/asm-powerpc/kprobes.h
index c16973d5de62..afabad230dbb 100644
--- a/include/asm-powerpc/kprobes.h
+++ b/include/asm-powerpc/kprobes.h
@@ -82,6 +82,7 @@ typedef unsigned int kprobe_opcode_t;
 
 #define ARCH_SUPPORTS_KRETPROBES
 #define flush_insn_slot(p)      do { } while (0)
+#define kretprobe_blacklist_size 0
 
 void kretprobe_trampoline(void);
 extern void arch_remove_kprobe(struct kprobe *p);
diff --git a/include/asm-s390/kprobes.h b/include/asm-s390/kprobes.h
index 8bc67cc9ffd2..948db3d0d05c 100644
--- a/include/asm-s390/kprobes.h
+++ b/include/asm-s390/kprobes.h
@@ -47,6 +47,7 @@ typedef u16 kprobe_opcode_t;
         : (((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR)))
 
 #define ARCH_SUPPORTS_KRETPROBES
+#define kretprobe_blacklist_size 0
 
 #define KPROBE_SWAP_INST        0x10
 
diff --git a/include/asm-sparc64/kprobes.h b/include/asm-sparc64/kprobes.h
index a04145b77f96..5020eaf67c29 100644
--- a/include/asm-sparc64/kprobes.h
+++ b/include/asm-sparc64/kprobes.h
@@ -10,6 +10,8 @@ typedef u32 kprobe_opcode_t;
 #define BREAKPOINT_INSTRUCTION_2 0x91d02071 /* ta 0x71 */
 #define MAX_INSN_SIZE 2
 
+#define kretprobe_blacklist_size 0
+
 #define arch_remove_kprobe(p)   do {} while (0)
 
 #define flush_insn_slot(p)              \
diff --git a/include/asm-x86/kprobes_32.h b/include/asm-x86/kprobes_32.h
index f2489d07ce88..b772d5b38685 100644
--- a/include/asm-x86/kprobes_32.h
+++ b/include/asm-x86/kprobes_32.h
@@ -45,6 +45,8 @@ typedef u8 kprobe_opcode_t;
 #define ARCH_SUPPORTS_KRETPROBES
 #define flush_insn_slot(p)      do { } while (0)
 
+extern const int kretprobe_blacklist_size;
+
 void arch_remove_kprobe(struct kprobe *p);
 void kretprobe_trampoline(void);
 
diff --git a/include/asm-x86/kprobes_64.h b/include/asm-x86/kprobes_64.h
index 3f495e5308b1..53f4d8507354 100644
--- a/include/asm-x86/kprobes_64.h
+++ b/include/asm-x86/kprobes_64.h
@@ -42,6 +42,7 @@ typedef u8 kprobe_opcode_t;
         : (((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR)))
 
 #define ARCH_SUPPORTS_KRETPROBES
+extern const int kretprobe_blacklist_size;
 
 void kretprobe_trampoline(void);
 extern void arch_remove_kprobe(struct kprobe *p);
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 51464d12a4e5..81891581e89b 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -166,6 +166,12 @@ struct kretprobe_instance {
         struct task_struct *task;
 };
 
+struct kretprobe_blackpoint {
+        const char *name;
+        void *addr;
+};
+extern struct kretprobe_blackpoint kretprobe_blacklist[];
+
 static inline void kretprobe_assert(struct kretprobe_instance *ri,
         unsigned long orig_ret_address, unsigned long trampoline_address)
 {
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index f9798ff7899f..e3a5d817ac9b 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -716,6 +716,18 @@ int __kprobes register_kretprobe(struct kretprobe *rp)
         int ret = 0;
         struct kretprobe_instance *inst;
         int i;
+        void *addr = rp->kp.addr;
+
+        if (kretprobe_blacklist_size) {
+                if (addr == NULL)
+                        kprobe_lookup_name(rp->kp.symbol_name, addr);
+                addr += rp->kp.offset;
+
+                for (i = 0; kretprobe_blacklist[i].name != NULL; i++) {
+                        if (kretprobe_blacklist[i].addr == addr)
+                                return -EINVAL;
+                }
+        }
 
         rp->kp.pre_handler = pre_handler_kretprobe;
         rp->kp.post_handler = NULL;
@@ -794,6 +806,17 @@ static int __init init_kprobes(void)
                 INIT_HLIST_HEAD(&kretprobe_inst_table[i]);
         }
 
+        if (kretprobe_blacklist_size) {
+                /* lookup the function address from its name */
+                for (i = 0; kretprobe_blacklist[i].name != NULL; i++) {
+                        kprobe_lookup_name(kretprobe_blacklist[i].name,
+                                           kretprobe_blacklist[i].addr);
+                        if (!kretprobe_blacklist[i].addr)
+                                printk("kretprobe: lookup failed: %s\n",
+                                       kretprobe_blacklist[i].name);
+                }
+        }
+
         /* By default, kprobes are enabled */
         kprobe_enabled = true;